All posts by Henry H

Junkers Ju 88S

Nazi Germany (1943)

Medium Bomber, Pathfinder: 362 Built

The fastest variant of the Ju 88, the S featured a massive increase in engine power and numerous aerodynamic improvements. (beeldbank)

The Junkers Ju 88 was among the most versatile and longest serving aircraft of the Second World War, and can be counted among the very few that weren’t completely obsolete at the end of hostilities. A modern design in the days preceding the war, it was intended to become the primary medium bomber in Luftwaffe service. In the following years, it to was to be replaced by the more modern Ju 288. However, production shortfalls made phasing out the dated Heinkel 111 unfeasible, and the Ju 288 would never see service, for a multitude of technical reasons. It thus fell on Junkers to keep the Ju 88 updated through the end of the war, producing a number of bombers, fighters, night fighters, and reconnaissance aircraft to service in whatever roles were needed. Among the last of these variants was the Ju 88S, which sought to produce the fastest bomber variant of the aircraft possible.

The Secret Airforce

The rearmament of the German air forces began covert program, with the government  hiding its efforts in both accumulating a pool of experienced airmen, and producing capable combat airplanes. The foundations of a new air force were laid during the Weimar period, where all of the existing civil airlines were merged into the state owned Deutsche Lufthansa enterprise under the directorship of Erhard Milch. Milch was a former Junkers employee, and future Inspector General of the Luftwaffe during the Second World War. In running Lufthansa, he created a pool of experienced pilots, aircrew, and maintainers under a single state enterprise, one which could provide the necessary expertise for providing the human resources necessary for any new military organization.

The task of arming this air force had to be achieved more covertly, and was pursued through two means. The first was simply to continue the production of civilian aircraft in order to maintain technical competence and an industrial base for building aircraft, and secondly, to design military equipment in secret abroad. The largest of these efforts was in the Soviet Union where several firms, the first being Junkers, built facilities supplied with shadow funding from the Weimar government. The Junkers plant at Fili, near Moscow, would sell military aircraft to the nascent USSR while gaining invaluable design and production expertise for facilities back in Germany.

Designed ostensibly as an airliner, the He 111 was the primary medium bomber of the Luftwaffe during the early stages of WWII. (wikimedia)

In the years to follow, German aircraft firms would go on to produce a number of dual-use civilian aircraft. Even before the rise of the Nazi party in Germany, this secret rearmament program was producing designs like the Junkers K-37 high speed mail plane, which was developed into a bomber in Japan as the Mitsubishi K-1 and 2. The designs of new military aircraft accelerated under the Nazi regime, who unlike their predecessors, were not simply interested in keeping pace in military aviation, but were now looking for weapons to defeat the United Kingdom, France, and the Soviet Union.

The new Luftwaffe was to have a very strong striking arm, and thus needed a bomber fleet. To meet this need, the government requested designs for high speed airliners and mail delivery aircraft that could double as light and medium bombers. By the end of 1935, this contest produced the Heinkel He 111, the Dornier Do 17, and the Junkers Ju 86. They were all capable, and very modern for their day, but with the expectation of conflict by around 1940 it was clear a second generation of aircraft would be needed to phase out these models once they began to show their age. The resources for this effort were in a competition between a large, four engine Uralbomber to strike at targets deep within the Soviet Union, and a smaller twin-engined Schnellbomber, a shorter ranged, more flexible medium bomber. The death of the Uralbomber’s strongest supporter, General Wever, and the more practical concerns of being able to support a fleet of heavy bombers, ensured the Schnellbomber’s ascendancy. Beyond this, the range of medium bombers was judged sufficient for war against France and Britain, who were seen as the primary opponents to the regime in the short term, and thus Germany would have the time to develop a heavy bomber later on for war against the Soviet Union.

This Schnellbomber was to be a fast medium bomber capable of engaging distant targets without need for an escort or heavy defensive armament. The requirements were listed as needing a top speed of 500 km/h, a 1000 kg bomb load, a range of 2500 km, and of course it needed to have a modest production impact, taking no more than 30,000 man hours to build. Junkers, and Willi Messerschmitt at the Bayerisch Flugzeugwerke, were the only major competitors, and though Messerschmitt’s Bf 162 was the simpler of the two, the design was not altogether finished at the time of its submission, and thus the Junkers Ju 88 was the clear front runner.

The Ju 88 went through considerable prototyping, this being the fifth, and far from the last. (prints online)

The Junkers Ju 88 was a modern, but not revolutionary design, it represented the most up to date concepts in airplane design, did but not incorporate any cutting edge technology. It was originally developed as a high speed level-bomber, but after the death of General Weaver, Ernst Udet was made the general Flugzeugmeister, the general inspector for the Luftwaffe. This change would result in severe complications to its, and other aircraft’s, development. A fervent advocate of the newly refined techniques of dive bombing, he made it a requirement that new bombers be made able to perform these attacks, which would require a substantial number of modifications to the design. Udet was a famed Great War aviator, but had very little in the way of engineering knowledge, and this decision slowed the development of the Ju 88, and largely doomed the later heavy bomber projects.

This requirement saw the program shift from the aircraft being a Schnellbomber to the multipurpose ‘Wunderbomber’, which required significant structural strengthening and the installation of dive breaks with an automatic recovery system. This added drag, weight, and delays in prototyping, but in the end, the design changes were worked into the aircraft satisfactorily. Production however was not forthcoming, as the German aviation industry would struggle to shift a massive proportion of capacity to building the new plane at an overly optimistic, and unreachable, rate of 300 per month. The plans for the plane were delivered in 1934, and the first prototype flew in 1936, but serial production only began in 1939. It wasn’t until 1940 that the Ju 88A-1 medium bomber was being produced at about ⅔’s of the desired 300 planes per month. It was the massive number of design changes resulting from the typical industrial corrections, the mission changes from the Luftwaffe, and simply basic design tweaks, that caused delay after delay.

Teething issues notwithstanding, the Luftwaffe had its most advanced bomber in the form of the Ju 88A. While it wasn’t the supposedly untouchable high speed bomber it was originally supposed to be, it was a multipurpose aircraft capable of carrying out a much wider number of missions. While it was slower than the original concept, it traded that speed for being able to engage large, mobile targets such as trains, columns of vehicles on roads, ships, and static point targets too small to be hit with level bombing.

The Early Years

Following its slow production during 1939, the Ju 88A was not employed widely until 1940, during the invasion of Norway. Its pilots were immediately appreciative of the plane’s superior handling and speed over the older bombers in service, and its dive attack capabilities were soon put to use. Equipped with the new aircraft, elements of Kampfgruppe 30 engaged a number of Allied ships during Operation Weserubung, badly damaging the cruiser HMS Suffolk, the French cruiser Emile, and sinking the destroyer HMS Gurkha.

While it was the fastest Luftwaffe bomber by a large margin, its crews were quick to learn that no matter its top speed, a bomber was always in danger without escorts. (albumwar)

It was during the invasion of Belgium and France that some of the design’s shortcomings became apparent, chief of which was its poor defensive armament and the limited fields of fire from the forward and top-rear machine gun positions. Not yet employed in significant numbers, the Ju 88 units on this front participated mostly in attacks against the French air force in suppressing their bases and attacking aircraft production. Beyond this they attacked port facilities and shipping to complicate the transportation of forces between Britain and the continent.

The attacks on the UK, culminating in the weeks that have come to be known as the Battle of Britain, would further demonstrate the destructive capabilities of the Ju 88, but also its vulnerability to fighters. In the end, bomber losses were high among all Luftwaffe units involved, with Ju 88 units specifically having trouble maintaining serviceability rates with their new aircraft. In short, both the RAF and Luftwaffe were pulverized and great damage was rained across much of Southern England, but in the end the defenders prevailed, and the Luftwaffe was forced to retreat and regroup.

As the campaign against England progressed, the Ju 88A was entering wider service and gradually replacing the obsolete Do 17. (rods warbirds)

Returning that fall, the Luftwaffe began the Blitz, nightly attacks against British cities conducted in the hope of breaking the resolve of the civilian populace. For the Germans, these raids would be less costly, but unlike earlier attacks on British production and shipping, there was little they could point to as a success beyond the acreage of burned out homes. The performance of the Ju 88 over the He 111 and Do 17 on these missions was largely a non-issue given the inaccuracy of nightly air defenses, and the small, but growing, RAF night fighter force. The true battle was being fought over the airwaves with the Luftwaffe using radio navigation aids to guide bombers to their targets, and the British sending out their own signals to disrupt them.

Adaptation

As with all military aircraft, design improvements were constantly being worked in via small changes, or different design variants. While there are few aircraft with as many variant designs as the Ju 88, these started simple. Initially there was a basic heavy fighter conversion of the Ju 88A-1, the Ju 88C-1 and 2. The glass ‘beetle’s eye’ nose glaze was replaced with a metal nose with fittings for 7.92mm machine guns, and 15 mm and 20 mm autocannons. These were built by modifying completed bombers, and in the earliest models, these fighters still had bombing gear and dive brakes. Beyond these easy converts, it was clear the basic bomber design itself could be significantly improved. The first major revision was in installing a set of long span wings and replacing the 1200hp Junker Jumo 111B’s for newer, more powerful models. While the more powerful Jumo 111J would not be produced in the numbers needed until 1941, implementing a new, longer span wing proved easy enough thanks to the modular construction of the aircraft. The revised design was the Ju 88A-5, which would go on to see service during the Blitz and the campaigns to follow.

The Ju 88A-4 offered a thorough improvement in performance, and a better defensive armament. (bundesarchiv)

The first thorough improvement to the design was the Ju 88A-4, which incorporated the long span wings, a redesigned rear canopy equipped with a second gun to improve firing arcs, better radio equipment, and the new Jumo 211J engines which each produced 200 PS more than the older Jumo 211B. This new design would prove to be the foundation for many more variants of the aircraft, all made to pursue different missions.

By the end of the Blitz, the Luftwaffe was having to contend with the nightly bombing of Germany by the RAF’s Bomber Command, and the Mediterranean theater, which featured action at very long ranges against maritime and ground targets alike. To suit these disparate needs, several new variant designs of the Ju 88A-4 were created. Mass produced heavy fighters were built to service long range day and night fighter squadrons, torpedo computers and shackles were added for anti-shipping units, and streamlined recon planes were built. Once the Jumo 211J was available in large numbers in 1942, Ju 88A-4 production would surge after pre-built airframes were finally receiving their new engines, and thus the number of Ju 88’s variants was expanded upon as well.

Mid War Service

By the end of 1942, the war had grown to four major fronts and the Ju 88 was used extensively on all of them. Over the Bay of Biscay Ju 88C-6 long range fighters flew cover for U-Boats, over Western Europe they served as night fighters, and across the Mediterranean and Eastern Fronts there were a great number of bomber, torpedo bomber, and photo reconnaissance units. However, near the end of 1942, the Ju 88A-4 derived models were starting to grow more vulnerable as the Luftwaffe’s fighter forces saw continued attrition. The Allied fighter forces were also growing considerably in strength, especially those of the UK and US who were building a considerable technological edge over their German opponents. With the Ju 288 having failed to materialize, Junkers would have to return to the drawing board with their old design.

This later Ju 88T recon aircraft features a number of aerodynamic improvements over the older models. With the aircraft’s lower ‘gondola’ section having been removed and having had the older ‘beetle’s eye’ nose replaced for a low drag glazing. This nose glazing first appeared on reconnaissance Ju 88s near the end of 1942.(asisbiz)

With the wings already having been modified, further performance improvements were to come through streamlining and new engines. In 1942, a proposed major redesign of the aircraft with a new, streamlined canopy was proposed and prototyped, but it was clear that the production delays in adopting this new Ju 88B would be unacceptable. The new cockpit would be included in the later Ju 188, but no major fuselage changes would be made on the Ju 88 for the rest of the war. Instead, a streamlined nose glazing would be considered, as would a new rear canopy hood with a defensive Mg 131 gun mount.

The only new major change in equipment was the introduction of the BMW 801 engine, which was now available in greater numbers, no longer reserved for Fw 190 fighter production. The Jumo 111J, even in its improved form, was growing increasingly obsolete as it had reached its operational limits. A successor design, the Jumo 213 with an improved pressurized cooling system, and designed to operate at much higher RPMs, was in development, but the reliance on second rate ‘economy alloys’ and resources being spread thin across several competing engine designs was causing long, painful delays. Once Germany’s access to molybdenum, tungsten, cobalt, and nickel were restricted by the Allied blockade, engine development ran into significant barriers. Thus, modified versions of older designs presented some of the few ways forward.

The BMW 801 promised a power increase of over 300 PS per engine, and beyond that it featured a highly advanced engine control system that meant the pilot only needed to adjust the throttle, and the system would adjust the RPM, boost, and mixture as needed. It’s only major drawback was its relatively dated single stage supercharger. Regardless, it represented the way forward for the Ju 88, and several new designs were drafted using this engine. The first of these were heavy fighters, which were much improved thanks to this massive increase in horsepower. The Ju 88R series would be the first mass produced variants to use this engine, but it still used an otherwise unmodified bomber airframe. There was much to be improved in regards to aerodynamics, especially in the case of the lower underslung ‘gondola’ which carried a pair of autocannons and a position for a ventral gunner on the Ju 88R. Further developments would see the removal of this feature, and net a massive reduction in drag, which would lead to the development of the final series of production Ju 88s.

The Ju 88S was delivered in a factory standard green/off white pattern, once they reached squadrons they were immediately repainted for night use. (hugojunkers)

These new models would be the Ju 88G, a night fighter, the Ju 88T, a reconnaissance aircraft, and the Ju 88S, a high speed level bomber and pathfinding aircraft. Apart from a few pieces of specialized equipment, and the larger vertical stabilizer on the Ju 88G, these aircraft shared the same supply chain, and the technical differences between them were so minor that they shared basic manuals. This would prove vital, as during this period, Inspector General Erhard Milch was attempting to rationalize all aircraft production into as few airframes as possible in order to increase overall production, and to ease the requirements of servicing aircraft. As part of this scheme, the Ju 88 would prove essential, with its single airframe fulfilling many of the most essential roles in the Luftwaffe.

The new Ju 88S, would resemble the recon plane almost entirely save for its lack of camera mounts. It was fitted with the low drag nose cone first installed aboard the earlier recon models, BMW 801D engines, and the dive brakes were removed. Compared to the Ju 88A-4, the top speed in a clean configuration was increased from 470 km/h to 588 km/h, at 6 km. At its maximum cruise speed of 460km/h, the plane nearly reached the maximum speed of the previous model. However, performance could be improved further at high altitudes using the GM-1 nitrous boost system. The system was simple, it used the nitrous as an oxygen carrier to increase the oxygen content of air entering the manifold at altitudes where the supercharger’s effectiveness fell off, and recovered engine performance otherwise lost to the thinner air. Using this system saw these planes reach a top speed of 610 km/h at 8km. Of course, carrying an external bomb load would seriously affect these speeds, but this boost in performance was remarkable. While the Ju 88S had sacrificed its dive bombing capability, it more than made up for it in sheer speed, which put it in the same league as the otherwise incomparable DeHavilland Mosquito Bomber.

The first of these planes was the prototype Ju 88V-56, which was followed by 24 production aircraft delivered up until June of 1943. These were not new airframes, however, but rebuilt Ju 88A-4’s, converted at Junkers Flugzeugwerk Magdeburg. Few major changes to this design were made until later, though the engines were soon changed to BMW 801G-2s, which was geared specifically for use in bombers.

Schnellbomber Once More

The first unit to receive these aircraft was Gruppe I of Kampfgruppe 66, this being a specialized pathfinding unit whose task was to lead bombers to their targets at night. They received the first of the aircraft of May of 1943, and were employed in small raids and reconnaissance operations over Southern England from their base in Chartres, France. One of the first losses came on the 30th, when one plane was shot down by a Mosquito night fighter, who pursued and intercepted them at 30,000ft. The crew bailed out, and the plane went down over England, its wreckage carefully picked over once the empty canisters of the GM-1 system were identified.

High contrast blue-gray and black patterns were preferred for night use as the upper sections would not stand out against clouds, and the countershading obscured the plane against the night sky. (rods warbirds)

The unit trained for raids conducted with conventional beam navigation systems, but also the newer EGON method. This system operated using one or more Freya radars which tracked the path of an aircraft by its Identify Friend-or-Foe transponder signal and guided it along its course toward the target via radio transmission. Such a system would require a well trained crew as the Freya’s lack of a height finding capability meant that careful attention would be needed to maintain the plane’s altitude while receiving directions from the ground controller. This system would be less vulnerable to jamming than the radio beam direction types that the British were already familiar with, but it still relied on the typical Luftwaffe communications systems, which they were also familiar with.

It wasn’t until 1944 that they were used for their intended purpose, during the revenge motivated Operation Steinbock, or ‘Baby Blitz’ as it came to be known. The previous year had seen an intensification of the Allied Bombing of Germany, especially with the highly destructive raids against the city of Hamburg, and the disastrous Bomber Command offensive against Berlin in the Winter. In the span of those six grueling months, Bomber Command went from its highest capability for destruction, to its worst blunder of the war so far. Despite the apparent futility of the assault on their own capital, Hitler wished to exact a cost on the British people, and Reichsmarshal Goering believed it was opportunity to show the lethality of his air force. The Luftwaffe had seen some improvements, and the addition of the massive, if troubled He 177 heavy bombers, gave the force a destructive new weapon. In contrast to the highest echelons of leadership, Colonel Dietrich Peltz, who was to direct the operation, wished to direct this concentration of bombers at Allied shipping, which he believed could damage their oceanic supply lines before an anticipated cross-channel invasion. He failed to convince either of his superiors, and thus proceeded with Operation Steinbock.

KG 66 was effectively the leading edge of the force which peaked at 524 planes, supplying a total 42 bombers, 23 being Ju 88S-1s. The general level of night flying proficiency among the raiders was poor, and thus the pathfinders were essential in leading the raiding force to their targets. The attack was to mirror the tactics of RAF’s Bomber Command, with light, specialized pathfinders plotting a route for heavy bombers carrying the heaviest types of bombs available, intermixed with smaller incendiaries, and fragmentation bombs on timers set to explode well after the raid ended. The assault began on the night of January 21/22, and it immediately became apparent that all of the existing guidance systems in use were compromised, even EGON to an extent. In spite of this, EGON was the primary system in use on these raids and was capable of high accuracy on nights without interference. On a night of poor visibility, the pathfinders failed to illuminate London, and only some 30 of 500 tons of bombs fell on the city that night. The RAF and the city’s Flak batteries would claim 20 planes, with 15 being lost to accidents.

As fast as the Ju 88S was, it was vulnerable to interception by the newest models of DeHavilland Mosquito nightfighters, which represented the deadliest nightfighters in use over Europe. (asisbiz)

However, the Luftwaffe was committed to the offensive, and launched another attack at the end of the month, and they returned to the city 7 more times in February, when the pathfinders had shown serious improvement. In March, they shifted their attention somewhat to Hull, and Bristol, but London remained their primary target, attacked five more times in March before the last major raid on the city in mid April. The Germans had little to show for their attacks, as while they had done a great deal of damage to the city, the worst since the Blitz, they found the Londoners as immovable as they had been near the start of the war. For their efforts, the Luftwaffe had largely expended their bomber forces, with Luftflotte 3’s Fliegerkorps IX now being left with 130 serviceable bombers. Reserves were drawn upon for replacements, and forces were redeployed from the Mediterranean, but there was nothing that could hope to challenge the 7000 planes of the Allied Air Forces across the channel. What might have been a potent strike force against the invasion was blunted in a shortsighted disaster that not only failed to take into account the lessons from Blitz, but what they themselves faced from Allies only a few weeks ago.

The Last Effort

I./KG 66 did not escape Steinbock untouched, losing about half of their aircraft, with only their Ju 88S and Ju 188 bombers remaining. However, as a specialized unit and one of the only users of the Ju 88S, they were soon supplied with fresh aircraft and set to a new mission. Steinbock had largely destroyed the Luftwaffe’s bomber forces, and thus there was little use for a pathfinder force tasked with directing large formations of bombers. The Luftwaffe’s fortunes had also declined since the futile offensive, as the American 8th and 15th air forces were employing long range escorts which now contested the airspace over all of Western Europe. When the Allies returned to France, they did so under the protective canopy of their fighter forces. To strike at the American and British armies now deployed to France, one of the few options available was to attack at night. With the bomber force having been depleted, it would thus fall to what remained, with assistance from night fighter squadrons, to carry out attacks against the Allied beachhead, supply lines, and frontline positions.

In this, I./KG 66 was perhaps the best equipped squadron for the task, having superior navigational training, and better aircraft than the typical raiders. Their operations were infrequent through the Autumn of 1944, while they rebased several times to keep ahead of the advancing Allied armies. Beyond this, there was a lull in night operations across the Western Front from roughly September to December. Their situation had deteriorated significantly, with chronic fuel shortages now being universal, and the Western Allies having succeeded in blinding German early warning systems by deploying ground based jammers to the continent.

A Ju 88S-1 in service with I. KG 66. (Cujo1970)

It was during the last month of 1944 that the last resources in the west that the Wehrmacht could muster were to be placed on an all-or-nothing offensive to stall the advance of the Western armies. Operation Wacht Am Rhein would involve throwing what remained of the Heer’s offensive capabilities at the Allies at a moment where they had outpaced their supply lines. One of the major deciding factors for the operation was the need for poor weather, to eliminate the Allied advantage in the air. For both sides of the coming battle, the only air units that could take part were those capable of instrument flying. For the Germans, this eliminated the use of all but the scarce remaining bombers, and their night fighters, which had become a second line night attack force since the Normandy landings.

KG 66 was to take a vital and early lead in the air operations during the offensive, where it would again act as a pathfinder force. They now also operated the Ju 88S-3 from their base in Dedelsdorf, Germany, this being a new subtype that used the more reliable Jumo 213A engines. Operations began on the night of December 17/18, with the Luftwaffe mounting some 243 night attack sorties. KG 66’s role was to aid in the navigation of night fighters, and to illuminate targets along the roads between Sittard, Maastricht, and Liege. Given the Allied supply situation, and the chaotic road traffic experienced across the front, these strafing and cluster bomb attacks would inflict considerable losses and sow confusion along the roads. Losses among the night fighters themselves were steep as despite the minor presence of allied night fighters, most of the Mosquito units had returned to the UK to receive the Mk XXX, and the use of proximity fused shells among flak units would prove lethal.

The night attack force would fly out the next night, with only limited success, but no losses. These attacks would continue throughout the offensive against rear line supply convoys, trains, and troop concentrations. They had some notable success, but at a very high cost to the night fighter force at a time when experienced aircrews could not be replaced. KG 66 would fare somewhat better given their less direct role in the assault, and would have an active strength of 29 Ju 88S-3s by January 10th, 1945. By this time, the S-3 was also found in the inventories of a number of standard bomber units. Outside of KG 66, the largest numbers of the aircraft were found in the first and second Gruppe of LG 1, a training unit now serving in combat, having been issued the aircraft the previous July.

 

As many Luftwaffe airfields were under threat from allied fighters through 1944, a reliance on secondary, concealed airfields was inevitable. (asisbiz)

For the next few weeks, what remained of the German bomber and night fighter forces of the Western front would be used as night harassment forces. Morale plummeted as there was little hope of anything being achieved in these costly actions, and the best of the RAF’s nightfighter forces were again on the continent. During these night raids, crews felt a constant anxiety over the presence of the Mosquito, which possessed both incredible speed and an endurance that allowed it to pursue targets on long chases. When these planes were found to be operating in a certain region, night attack sorties for the night were called off. Such notices came at a great relief to the dwindling number of bomber and night fighter crews who were called upon to support the army as it retreated ever deeper into Germany itself. In the final weeks of the war, KG 66 was merged with KG 200 and participated in night harassment sorties until the capitulation of the German armed forces.

Handling and Use Characteristics

The Ju 88S retained the good flying characteristics the series was known for. It featured well harmonized, responsive controls that remained light at higher speeds, and provided responsive take off and landing characteristics. The use of the highly automated BMW 801 and Jumo 213 engines also removed a substantial amount of workload for the pilot, who only needed to adjust the throttle to bring the aircraft to its various power settings. Combined with the level, azimuth only autopilot, the Ju 88 was an aircraft many Luftwaffe crews felt confident in flying hands off for extended periods of time. This would prove essential considering the mostly nocturnal sorties, where pilots flew by instruments, and needed to pay close attention to the various navigational signals guiding them to their targets. Overall, the Ju 88 can be described as a vice-less aircraft with very forgiving handling.

It would also prove to be incredibly fast, with a clean configuration allowing the Ju 88S-1 to reach 588 km/h at 6 km. Using various boost systems allowed the aircraft to reach higher speeds. GM-1 nitrous boosting allowed the S-1 to reach 610 km/h at 8 km, with the S-3 being able to reach 615 km/h. At lower altitudes, the S-3 could make use of methanol-water injection to allow the engine to produce considerably more power. While no data is extant on performance of the aircraft with this system, crew testimonies claim the heavier Ju 88G-6 night fighters were capable of exceeding 600 km/h at lower altitudes using MW50.

The Ju 88 gained a reputation for being easy to fly, with advocates on both sides. (asisbiz)

Famed Royal Navy pilot Capt. Erik ‘Winkle’ Brown would also be among the few allied pilots to have had the opportunity to fly many models of the Ju 88, from bombers to night fighters. Capt. Brown felt the aircraft possessed largely the same excellent handling characteristics from the Ju 88A-5 medium bomber to the Ju 88G-6 nightfighter. He praised it for its easy ground handling, thanks to its excellent brakes, it’s good handling during climbs, and light controls at cruising speed.

Capt. Brown would spend more time with the G-6, a variant very similar in construction to the Ju 88S-3, and was able to put one through more demanding tests. Having previously flown several versions of the Ju 88, Brown was particularly impressed by the high speeds he reached in a Ju 88G-6 (Werk-nr 621965). The aircraft remained in line with his general, glowing remarks over the Ju 88. “It was a pilot’s airplane, first and last, it demanded a reasonable degree of skill in handling and it responded splendidly when such skill was applied. There was a number of very good German aircraft but, with the exception of the Fw 190, none aroused my profound admiration as did the Junkers ‘eighty-eight’.”

Perhaps the simplest, but greatest, advantage the aircraft had was in the close proximity of the crewmembers, which allowed them easy communication in the event of intercom failure or emergency. It also allowed the pilot to be seated beside the gunner and flight engineer, an ideal arrangement providing both easy communication and good situational awareness. This arrangement also provided good protection from rearward attacks, with the armored gunner’s position and the bulkhead armor between the crew and any attacker. Should all else fail, the bail out procedure was as simple as it could have been. The entire rear of the canopy detached, allowing for all of the crew to bail out from the shared compartment.

The general design of the aircraft was modular, with the wings, stabilizers, and engine units being attached to the aircraft by very robust, but easily removable connectors. Thus, the maintenance, replacement, or adjustment of any one of these components was made far easier. This lent to an overall ease of maintainability for the ground crews who could perform dreaded tasks like engine replacements rapidly, and without much exertion. The unified engine units could simply be disconnected and pulled away from the mount.

While it inherited the benefits of the original design, it also had its flaws. The most obvious of which was the poor visibility due to the bars of the reinforced cockpit frame, which reduced visibility, and the troublesome landing gear which had a tendency to buckle if the aircraft was brought down too hard. The landing gear was a hydraulically actuated set that rotated 90 degrees so that the wheels would lie flat within their nacelles. This greatly reduced drag, as the shallower landing gear bays contributed far less to the frontal area of the plane, but they could be broken in hard landings or harsh ground maneuvers while carrying a heavy payload. These types of accidents were typically handled by the local repair staff, but greater levels of damage often called for an aircraft to be disassembled and sent to repair depots, or factories, for restoration.

The most common accidents with the plane were landing accidents involving flipping the plane over onto its nose. Due to the forward placement of the engines, it wasn’t uncommon for the plane to flip over forward while landing, when less experienced pilots were too heavy on the brakes. These typically resulted in little more than damaged propellers and smashed nose cones, and thus didn’t remove an aircraft from service for very long. In more drastic cases the plane could be flipped onto its back and injuring the crew.

Production

As one of the more minor variants of the Ju 88, the S was manufactured across several facilities, with both new built, and modified production models. The Ju 88S-1 was entirely an Umbau series, a modified production aircraft built from new Ju 88A-4 airframes. These were produced at the Junkers plant in Magdeburg, with the first deliveries arriving in the Spring. At Magdeburg, a total of 57 planes were manufactured in 1943, with 14 more being built the following year, with production being terminated in May.

The Ju 88S-3 incorporated the newer Junkers Jumo 213A engines, its performance was not significantly altered, but the engine was more reliable and in greater supply. It was the only variant to be mass produced as newly built, rather than modified aircraft. (rods warbirds)

The Ju 88S-3 was built as both new airframes, and modified production aircraft. All of the new production aircraft were built at the Henschel Aircraft Factory in 1944, beginning in June. Here, they replaced the production of the Ju 88A-4, with a total of 264 rolling off the line in 1944, and 12 more the following year. The Henschel plant built another 15 from Ju 88A-4s. The Ju 88S-3 was by far the more prolific of the two and wasn’t just regarded as a specialized aircraft, with many deliveries being made to standard bomber squadrons. Apart from these bombers, Deutsche Lufthansa at Berlin-Staaken converted 3 Ju 88S-3’s to high speed couriers and transports.

The production of the Ju 88S itself continued at a fairly high pace for a specialized design well into 1944, when bomber production was drastically cut in favor of fighters. There was also a declining interest in pistoned engine bombers, as the German aviation industry began to produce a growing number of jet aircraft. The Arado 234 was seen as an obvious successor, being the only reconnaissance plane that was truly non interceptable.

The build conditions of these aircraft declined precipitously between 1943 and 1944 as the German war effort ran short on key materials and an ever growing number of factory workers were drafted. This hit a critical level in 1943, where the mass use of forced labor became the standard across most wartime German industries. In aviation, it had become an accepted practice the previous year, with concentration camp inmates being made to work at a number of plants. As the German labor pool continued to be drained, an even larger proportion of forced laborers were used, now drawing large numbers from the concentration camp system, and forcefully deported workers from Eastern Europe. This change saw a vast drop in working conditions and a large increase in sabotage; production quantities surged while quality backslid considerably. This process was overseen by Erhard Milch, inspector general for the air force, and armaments minister Albert Speer. They expanded upon the use of forced labor drastically in early 1944, following the American Air Forces targeting of German fighter production. This enabled them to build more aircraft than ever before, but saw a sharp increase in rates of sabotage and an overall decline in quality.

Much of this production strategy also relied on corner cutting and the implementation of extremely long work hours, with a 72 hour work week eventually becoming the standard. In terms of materials, they cut back the production of spare parts, began to accept well-used parts in new production aircraft, and recycled refurbished equipment from written-off planes. The production of all but a small, but crucial number of fighter, night fighter, and reconnaissance models were cut drastically or eliminated. Overall, this strategy allowed them to drastically boost fighter production in the short term, but the rate could not be maintained and declined in the fall of 1944, only a few weeks after its peak.

Construction

Fuselage

The Ju 88A-4 was the most widely produced bomber variant and formed the basis of the Ju 88S’s design. This was also true in a literal sense, with many of the new models being built from existing A-4s. It was conventional all metal aircraft in its construction, and, while it pushed few technical boundaries, it was state of the art and versatile. It was primarily made of sheet aluminum fastened by rivets, with cast parts used for load bearing elements. Some use of Elektron magnesium alloy was made to further reduce weight, but later in the war this had been replaced by steel, which was primarily used in the landing gear fittings. The fuselage cross section was rectangular with rounded corners and clad in large sheet aluminum stampings. It used a semi-monocoque structure made up of formers and bulkheads joined by connectors that ran front to aft, with the outer aluminum skin riveted to both elements, which allowed it to bear some of the structural load. Its structural load factor was 4.5 with a 1.1 multiplier for the first wrinkle, 1.3 for yield, and 1.8 for failure. In service, it proved very sturdy, with Junkers engineers claiming after the war that there had been no reported major structural failures over the service life of the airframe.

Modularity was a key feature of the Ju 88, allowing for simple modifications to the design, and ease of field maintenance. (Ju 88S flugzeug handbuch)

By the time of the Ju 88S, the construction process had been improved to the point where the fuselage was built from sub-assemblies that would become the upper and bottom halves of the fuselage. These would then be joined together after wiring and internal components were fitted. Wing construction followed a similar process, making heavy use of sub assemblies, followed by equipment installation, skinning, and painting.

Wings

The Ju 88’s wings were the heaviest part of the aircraft, comprising much of its total structural weight at over 1200 kg. A pair of massive main spars ran from the root to the wing tip, a rear spar ran across the entire span of the wing to support the flaps and aileron. Two forward spars ran from the engine nacelles to the fuselage to transfer thrust from the engines and support loads from the landing gear. These spars were joined by relatively few airfoil shaped ribs and stiffened with corrugated aluminum. The wings were joined to the fuselage by means of four large ball-screw connectors, which made for easy assembly and alignment.

 

Wing connecting system (Ju 88A-4 Bedieungsvorscrift 1941)

The vertical stabilizer was fixed to the fuselage by means of the same ball-screw connectors as the wings. Installing it was simple, with the rudderless stabilizer being fitted to the fuselage, and the rudder fin being affixed afterwards. The horizontal stabilizers did not use the same fitting system. Instead, they were each inserted into the fuselage by two spars which were then bolted together.

As previously stated, the landing gear could prove troublesome due compromises in its design. During early prototyping, Junkers redesigned the landing gear into a single strut that would rotate so that it would lie flat beneath the wing when retracted. While this did remove the frontal area that would have seriously impacted the aircraft’s high speed performance, it came at the cost of added complexity and made for a far less robust landing gear arrangement. Differing from earlier series, the Ju 88S’s landing gear frames made use of welded cast steel instead of light weight alloys.

The wings were also equipped with an excellent de-icing system which took in air, ran it through a heat exchanger around the exhaust ejector stacks, drove it through channels in the wings, and then out over the ailerons. As the BMW 801 had no exhaust stacks compatible with this system, they made use of a petrol-fired heater to supply air to the de-icing system on the Ju 88S-1.

 

The highly effective de-icing system made Ju 88s a comparatively safe aircraft to fly under the worst winter conditions. (NACA)

 

Engines

In addition to its high power and automation, the BMW 801 was well protected, with armor plate around the front of the engine, protecting the oil cooler. (smithsonian)

Apart from the initial use of BMW 801D’s, the Ju 88S used two engines in service, the BMW 801G-2 and the Junkers Jumo 213A-1. The BMW 801G-2 was a 14 cylinder, 41.8 liter radial engine which produced a maximum of 1715 PS at 2700 rpm. It had a bore and stroke of 156 mm by 156 mm, weighed 1210 kg, had a compression ratio of 7.22:1, and ran on C3 95 octane aviation gasoline. It was equipped with a single stage, two speed supercharger that gave the engine a full throttle height of 6 km. Despite its lackluster high altitude performance, the engine had a massive advantage in its high level of automation. Designed with an mechanical-hydraulic computer, called the Kommandogerät, the pilot needed only to adjust the throttle to bring the engines to a higher or lower power setting. RPM, mixture, and boost were all managed by this system, and massively reduced the pilot’s workload. The BMW 801G-2 would be installed aboard the Ju 88S-1 before later being replaced with the Jumo 213A-1 on the S-3.

The Jumo 213A was a 35 liter, inverted V-12 that was derived from the earlier Jumo 211. The new engine was designed to work at significantly higher RPMs and featured a new pressurized cooling system, which kept the internal pressure stable regardless of altitude. The engine ran on B4 gasoline, which was approximately 89 to 91 octane by the stage of the war this aircraft was used. The primary issue with the older Jumo 211 was its open cooling system which left it open to the effects of external air pressure. At higher altitudes, the lower boiling point of water severely impacted high altitude performance. The new engine possessed a smaller block, a more powerful supercharger, and an automated control device, like that on the BMW 801, called the Bediengerat. The A, being a low altitude model of the engine, had a single stage, two speed supercharger.  This gave the engine a full throttle height of around 6 km, roughly the same as the BMW 801. The engine had a bore and stroke of 150mm by 165mm, a weight of 940 kg, a compression ratio of 6.5:1, and it produced 1775 PS at 3250 RPM. A large annular radiator provided cooling for the engine’s pressurized cooling system, and oil.

The Jumo 213A was the preferred engine for Ju 88 crews, owing to its higher reliability. Note, this engine is displayed upside down. (aerofossile2012)

Both engines were installed in ‘Kraftei’ units which placed the engine and its associated cooling systems within a single, unified arrangement. These allowed for a great ease of maintenance, as the entire engine could be easily removed and replaced. These engines were fitted with VDM and VS-111 propellers on the BMW 801G and Jumo 213A respectively. Both engines employed direct fuel injection.

Fuel System

Fuel capacity varied dramatically depending on the mission loadout, as the rear fuselage tank would be removed in order to carry the GM-1 or MW 50 bottles. Fuel tankage consisted of multiple wing tanks contributing 1680 liters, a forward fuselage fuel tank of 1220 liters, a rear fuselage tank of 680 liters, and up to two external fuel tanks of 900 liters. At the lowest fuel capacity of 1680 liters, the Ju 88S-1 could fly a maximum of 1130 km at a cruise speed of 420 km/h, or 750 km at a maximum cruise speed of 460 km/h. At a maximum fuel capacity of 3580 liters, this was increased to 2415 km at low cruise, and 1590 km at high cruise.

The maximum fuel tankage of the Ju 88, 7 & 8 are oil, 9 is the emergency raft and beacon kit. (Ju 88A-4 Bedieungsvorscrift 1941)

Endurance with the Jumo 213A-1 powered Ju 88S-3 was somewhat lower, with a reduced fuel capacity of 1680 liters giving the aircraft a range of 1000 km at cruising speed of 410 km/h, and a range of 900 km at a maximum cruise speed of 450 km/h. The maximum operational fuel load was reduced to 2900 liters, which permitted a range of 2050 km at low cruise, and 1570 km at high.

Engine Boost Systems

The Ju 88S-1 could carry the GM1 high altitude boost system, and its successor, the S-3 could carry this system and the low altitude MW 50 low altitude boost system. The GM1 system was a nitrous boost system which provided high oxygen content to the engine at altitudes where the super charger failed to provide a boost with enough oxygen content to run the engine at its higher power settings. The mixture was delivered into the supercharger intake by means of compressed air. Activating the system was done by flipping the activation switch in the cockpit, which was accompanied by gauges showing the pressure remaining in the system. The activation time was approximately five minutes.

The high altitude boost systems allowed the Ju 88S to evade all but the fastest night fighters in Allied service. (candvt)

The chilled liquid nitrous was stored in insulated bottles, in either a three bottle arrangement, where each held approximately 90 liters, or a single large container containing approximately 284 liters. The flow of nitrous was either 3.26 kg per engine, per minute, or when set to the emergency setting, 5.98 kg per engine per minute. The emergency setting was typically ignored, as it was seen to cause engine trouble. In the three bottle version, the boost could be sustained for a non-consecutive 45 minutes, or 27 at the emergency setting. The chilled nitrous also aided in reducing knock via charge cooling. It should be understood that this system does not boost the maximum power output of the engine, but is rather a method of recovering power lost due to the thinner air at high altitudes. The activation height for the BMW 801 was 7 km, below which it offered no benefit.

MW 50 was a low altitude boost system to increase the maximum power output of the engine. This is done by reducing knock and allowing the engine to run at manifold pressures far higher than normal. This is achieved by increasing the overall octane rating of the fuel by adding methanol, rated at approximately 115, and water, which allows for a denser airflow at the manifold via charge cooling. This allowed the Jumo 213A to run at 2100 PS, roughly a 325 PS increase. Use of the system was rare on the Ju 88S.

It was not without its drawbacks. Firstly, the mixture was highly corrosive, and even with its anti-corrosion additive, it markedly shortened the lifespan of the engine. Second, was that it was restricted to use at lower altitudes. Unlike GM1 which was from pressurized air bottles, MW 50 was supplied into the supercharger via a pump. After rising above the supercharger’s maximum effective height, pressure in the system would fall until it offered no benefit to performance.

Crew Accommodations

The crew arrangement on all Ju 88 models would set the entire crew within the canopy and in close contact with one another. The bombardier sat to the pilot’s right, a flight engineer/gunner at the pilot’s back, and a ventral gunner sat beside the flight engineer or in a prone position inside the “gondola”, where his weapon was located. Aboard the Ju 88S, the ventral gunner’s position had been omitted with the removal of the gondola, however the positions of the other crew members remained largely unchanged. While these close quarters arrangements were somewhat claustrophobic, they ensured easy communication between the pilot and the rest of the crew at all times. It also made for a much simpler bail out procedure, as half the canopy would detach and allow for a quick escape for all aboard. In the Ju 88S, the crew entered the aircraft through a hatch below the cockpit.

Armament

The aircraft came equipped with a pair of ETC 500 underwing racks which could support a payload of up to 1800kg per shackle. These two pylon positions were plumbed to allow them to mount a pair of 900 liter external fuel tanks. It was possible to mount a second pair of ETC 500 racks could be added beside the standard two, though this does not seem to have been carried out in the field. The Ju 88S retained the internal bomb stowage, and could be used to carry small diameter bombs or extra fuel. Apart from flares and small incendiaries that could be accommodated by this bomb bay, most of the weapons used were larger diameter bombs mounted to the external shackles, being either conventional high explosive or anti-personnel cluster bombs.

The internal bay could only accommodate small diameter bombs, and was often used to carry either extra fuel, or GM 1 cannisters. (Ju 88A-4 Bedieungsvorscrift 1941)

The single 13 mm MG 131 was placed at the rear of the canopy within an armored glass mount and supplied with 500 rounds of armor piercing and high explosive shells in equal proportion.

Avionics

The Ju 88S was typically equipped with the following devices: FuB1 2 (Blind approach receiver), Fug 10P (radio set), FuG 25 (IFF), FuG 101 (Radio altimeter), and in rare cases the FuG 136 (pathfinder command receiver).

The FuB1 2 was a blind landing system that guided the aircraft onto a runway by way of two radio beacons placed at 300 m and 3000 m away from one end of the airstrip. It was a tunable device so that airfields could possess separate frequencies between 30 and 33.3 mHz. The aircraft itself carried the Eb1 2 beacon receiver, the Eb1 3F beam receiver, the FBG 2 remote tuner, the AFN 2 approach indicator, the U8 power supply unit, and either a mast or flush antenna.

The FuG 10 was designed to be easy to maintain with its universal frame and swappable modules. (pa0pzd)

FuG 10P was a radio developed by Telefunken and was coupled with the Pielgeräte 6 radio direction finder. The device consisted of numerous transmitters and receivers capable of operating at various ranges. Each component was fitted in a modular box which was connected to a wall rack to allow for the quick replacement of damaged components. One pair, E10 L and EZ 6, operated at between 150-1200kHz, and another, S10 K and E10 K, between 3-6mHz. Other components included the U10/S and U10/E power supply units, and the fixed antenna loading unit AAC 2. Numerous versions existed and made use of various other components.

FuG 25 “Erstling” was an IFF system manufactured by GEMA that would respond with coded impulses to the ground-based Wurzburg, Freya, and Gemse radar systems up to a range of 100 km. The receiver operated on a frequency of 125 mHz and the transmitter at 160 mHz. The entire unit was contained within the SE 25A unit, with the BG 25A control box in the radio operator’s station. This unit was used to facilitate the use of the EGON navigation system wherein a pair of Freya, or Wasserman, radar stations would ping the IFF. Finding its direction, gauging the signal strength, and triangulating its angle between the radar stations allowed the ground controllers to accurately set the position of the aircraft against a plotting table. Navigational commands were issued over wireless telegraph or a specialized device, the FuG 136 Nachtfee.

FuG 101 was a radio altimeter designed by Siemens/LGW with a maximum range of 150-170 m and operated on a frequency of 375 mHz at 1.5 kW. Accuracy was within 2 m and the entire system weighed 16 kg. It consisted of the S 101A transmitter, E 101A receiver, U 101 power supply unit, and the pilot’s panel indicator.

FuG 136 Nachtfee

On the right is the read out for the aircraft based receiver, the notch at twelve o’clock would represent one of over a dozen commands. Note the display is from the ground unit. (candvt)

This communication device consisted of a CRT indicator aboard the plane which received commands from a ground based control console, using the EGON navigation system. These commands were represented by a 12 position, clock-like display, where each position represented a different navigational command. These were sent to an aircraft’s onboard FuG 25 IFF system via transmission pulses from the ground based radar. In addition to the 12 commands, based on the position of the pulse, an additional 4 commands could be given with a double pulse. For example, a transmission of position 1 followed by position 2 would be an entirely different command than simply just one on position 1. The device required constant monitoring by a specialized crew member.

 

Conclusion

Out to pasture. (wiki)

The Ju 88S would prove a tremendous improvement to Junker’s ever versatile bomber, achieving extremely high speeds and proving a difficult target to intercept. In terms of its sheer performance, Junkers was successful both in keeping their bomber from falling obsolescence, developing an airframe which was very successful both as a medium bomber and night fighter. However, nothing could prevent the eventual undoing of the Luftwaffe, from both the British and American Air Forces, and the terrible, short sighted decision making that dominated the upper echelons of power in the Third Reich.

Variants

Ju 88S-1: Bomber-Pathfinder equipped with BMW 801G-2 engines. 71 Built.

Ju 88S-2: Bomber-Pathfinder equipped with BMW 801T turbocharged engines. Experimental, none built.

Ju 88S-3:Bomber-Pathfinder equipped with Junkers Jumo 213A-1 engines. 291 Built.

Ju 88S-3 Highspeed Courier: Deutsche Lufthansa fast transport and mail carrier. 3 converted.

Ju 88S-4: Bomber-Pathfinder equipped with Junkers Jumo 213A-1 engines and vertical stabilizer from Ju 188. None built.

Specifications

Ju 88S-1 (Ju 88S-3) Specification
Engine BMW 801 G-2 (Jumo 213 A-1)
Engine Output 2×1715 PS (2x 1775 PS [MW50: 2100PS])
Empty Weight 8350 kg (8420 kg)
Loaded Weight 13650 kg (14040 kg)
Maximum Range (no weapons, max fuel) 2415 km (2050 km)
Maximum Endurance 5hr 45min (5hr 20min)
Maximum Speed [at altitude] 588 km/h at 60 km (580 km/h)
Maximum Speed with w/ GM1 at 8km 610 km/h at 6km (615 km/h at ~5.5 km)
Armament 1xMG 131
Crew 1 Pilot, 1 Radar Operator, 1 Flight Engineer/Gunner
Dimensions
Length 14.36 m
Wingspan 20.08 m
Wing Area 54.5 m2

Combat range varied dramatically depending on the fuel, weapon, and boost system arrangement. A Ju 88S-1 carrying pair of 250 kg bombs, and equipped with GM-1, had a combat radius of 330km. Without GM 1, its combat range was otherwise comparable to the Ju 88A-4.

Illustration

 

This polka-dot pattern was used by the pathfinder unit KG 66 from the spring of 1943 until the end of the war.
This paint scheme was used by LG 1 during the last offensive on the Western Front and the following retreat into Germany.

Credits

Written and Edited by Henry H.

Illustration by Arte Bellico

Sources

Primary:

A.D.I. (K) Report No. 357/1945. Radio and Radar Equipment in the Luftwaffe II. 1945.

Ju 88S-1 Flugzeug Handbuch. Junkers Flugzeug und Motorenwerke A.G., Dessau. 1944.

Ju 88S-1 Flugzeug Handbuch Teil 12 G Rüstsätze (Stand Marz 1944). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. 1944.

Ju 88S-1 Flugzeug Handbuch Teil 12 D Sondereinbauten Heft 4: Sonderstoffanlage (Stand Marz 1944). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. 1944.

Ju 88A-4 Bedienungsvorschrift-FL Bedienung und Wartung des Flugzeuges. Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. Juli 19, 1941.

Ju 88G-1 Schusswaffenlage Bedienungsvorschrift-Wa (Stand Oktober 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. November 1943.

Ju 88 G-1,R-2, S-1,T-1 Bedienungsvorschrift-Fl (Stand November 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. December 1, 1943.

Ju 88 G-2, G-6, S-3, T-3 Bedienungsvorschrift-Fl (Stand September 1944). 1944.

Rodert, L. A., & Jackson, R. (1942). A DESCRIPTION OF THE Ju 88 AIRPLANE ANTI-ICING EQUIPMENT (Tech.). Moffett Field, CA: NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS. 1942.

Secondary:

Brown, Eric Melrose. Wings of the Luftwaffe. Hikoki, 2010.

Medcalf, William A. Junkers Ju 88 Volume One From Schnellbomber to Multi-Mission War Plane. Manchester, UK: Chevron Publishing Limited , 2013.

Medcalf, William A. Junkers Ju 88 Volume Two The Bomber at War Day and Night Operational and service history. Manchester, UK: Chevron Publishing Limited , 2014.

Green, William. The warplanes of the Third Reich (1st ed.). London: Doubleday. 1972.

Bergs, Christopher & Kast, Bernhard. STUKA The Doctrine of the German Dive-Bomber. Lulu Press. 2022.

Boitens, Theo. Nachtjagd Combat Archive 24 July – 15 October 1944 Part 4. Red Kite . 2021.

Boitens, Theo. Nachtjagd Combat Archive 16 October – 31 December Part 5 1944. Red Kite . 2021.

Boitens, Theo. Nachtjagd Combat Archive, 1 January – 3 May 1945. Red Kite . 2022.

Bauer, Arthur .O. Nachtfee-EGON. 2012. https://www.cdvandt.org/

Bauer, Arthur .O. Nachtfee. 2012. https://www.cdvandt.org/

Junkers J.I

German Empire (1917)

Reconnaissance and Infantry Liaison aircraft: 227 Built

Intro

The Junkers J.I represented a massive leap in aircraft design philosophy, while also being a truly exceptional combat airplane in its own right. Designed to fly close along the frontlines and support infantry operations, the J.I was uniquely capable thanks to its armor plated fuselage and duralumin construction. It was exceptionally durable, able to resist both machine gun fire and weather that kept its wood and canvas contemporaries grounded. As a reconnaissance, supply delivery, and ground harassment aircraft, the Junkers J.I was both the best of its day, and a sign of things to come.

Professor Junkers

Hugo Junkers holds a position of immense importance in aviation, being the creator of the all-metal airplane and the founder of one of history’s most famed airplane firms. Junkers himself was born in February of 1859 in the Rhineland Town of Rheydt, the third of eight children. He would not stay and work at the family textile company after leaving school, instead going on to study at the Universities of Berlin-Charlottenburg, Karlsruhe, and Aachen. He completed his studies in 1888, obtaining a degree as a Baumeister, or factory official, and entered the field of gas engine design in Wilhelm von Oechelhauser’s firm, the Deutsche Continental Gasgesellesschaft. In time, the two of them would go on to found a new joint venture, the Versuchsstation fur Gasmotoren von Oechelhaeuser und Junkers, a laboratory for gas engine development. His work at this laboratory would go on to see him develop the first opposed piston, two stroke engine, calorimeters for testing gasoline, and many smaller domestic appliances from gas stoves to water heaters. It was in 1895 that he founded Junkers and Co. in Dessau to manufacture these appliances, this venture also being the foundation for his later efforts in aviation.

Hugo Junkers circa 1920, following the end of the great war his firm built the first modern airliners. (wikimedia)

In 1897, he would both be made a Professor of Thermodynamics by the University of Aachen, and he would marry his wife Therese Bennhold. At the university, he was made head of the engineering laboratories, and founded his own workshop there to secure a place to continue his experiments. His work there would progress quickly from both his personal drive, and considerable funds from the patent revenue from the products he developed. This combination of experience with metalworking, a secure lab, and his considerable engineering talents, would see Prof. Junkers enter the field of aviation well equipped.

It was in 1910 that his colleague Prof. Hans Reissner would suggest he venture into the field of aviation, and the two would work together at the University of Aachen, building an experimental wind tunnel, and a very early all-metal airplane prototype. As these projects continued, he would go on to move all of his work to his own laboratory in Dessau. At this new lab, Dr. Junkers combined the experimental wind tunnel work from Aachen with his theories on aircraft design, notably, that of all-metal construction.

The Tin Donkey

Prior to the 1920’s the conventional materials and layout for airplane construction was a biplane made from wood, and skinned in fabric, with struts and bracing wires providing the structural support for the wings. Prof. Junkers felt that the inherently high parasite drag of biplanes, combined with the external supports, was a major handicap in aircraft design, and he believed that metal construction would completely revolutionize airplane development. Using a thick, rigid wing that was internally supported, the resultant aircraft would be aerodynamically cleaner, and the internal space within the wing could be used to store fuel or cargo.

His first major effort to build such an aircraft began near the end of 1914, as a privately funded venture with the assistance of the engineers Otto Reuter and Otto Mader. Initially, the project was funded by a large influx of cash from Junkers and Co., but they received Military support by June of 1915, and they were contracted by the Army to produce the new aircraft. Supplied with tooling and material’s from Dr. Junker’s own enterprise, they proceeded, and in four months they had built their plane.

 

The J.1 during its Army test flight. Despite their extremely similar designations the J.1 and J.I are completely different aircraft. (SDASM)

The Junkers J.1 was as revolutionary a design in airplane development as had been seen since the invention of the plane itself. It was a steel mono winged plane, and the first to feature cantilevered wings, which were spar-less and consisted of a steel framework welded to an inner, corrugated skin, over which it was skinned in smooth sheet steel. Aluminum alloys were sought after, but in the end, steel was all that was available. It proved to be an extremely sturdy, but also very heavy aircraft, weighing in at 1010 kg when set for takeoff. Beyond the original benefits Prof. Junkers envisioned for his new planes, the war, and the subsequent mass production of airplanes had shown there were more practical challenges in operating wood and fabric aircraft. As the number of airplanes increased, storage space became a premium, and canvas biplanes cannot be allowed to sit in poor weather lest their wooden frames and canvas skin become warped. Pilots in combat also soon discovered their greatest fear beyond the enemy’s guns, fire, which no matter how minor at first, often became a death sentence to anyone who’s plane began to burn. However, a metal aircraft with a canvas cover can sit in nearly any weather without issue, and a fire aboard such a plane isn’t liable to spread rapidly. A pilot could ditch his plane in most circumstances, saving him from a very grisly end.

The J.1 was taken to Doberitz where it would be tested by the Army, as Dessau lacked a proper airfield. Lt. Theodore von Mallinckrodt of the German Army would be the first to fly it, finding some novelty in a metal aircraft. Much of the test team was critical of the new plane, nicknamed the ‘tin donkey’, feeling that it would be too heavy to fly, and that it was suicide to fly a plane without bracing wires. Unbothered, the lieutenant began with short hops along the ground before the first full flight test in December. It flew well at first, but with harsh vibration being noted once the plane was brought to high speed. The Army team found the flight characteristics acceptable, but found that the wings had compressed the fuselage of the plane. They were also critical of its extremely low climb rate and lackluster turning performance, but all were impressed when the aircraft achieved a speed of 170 km/h in level flight, making it the fastest plane yet built. Even with its modest 120hp straight 6 Mercedes engine, its speed managed to impress ace pilot Oswald Bolcke who had a chance to inspect the aircraft the next year.

As an experimental aircraft, it was an undeniable success, having proven both that an all metal aircraft was well within the material restrictions of the time, and that massive reductions in drag were possible using this construction. The experimental plane was thus followed by a fighter aircraft, the Junkers J.2. Similar to, but far more refined than the ‘tin donkey’, the J.2 was the first all-metal fighter aircraft ever designed, but it was never accepted for service and the Idlfieg lost interest when it was clear certain performance metrics could not be met. As with the J.1, the fighter still used a 120hp engine, and with its smaller wings, it possessed even higher wing loading, as well as the sluggish climb rate of the experimental J.1. A new 160hp Mercedes engine also failed to bring the aircraft up to the necessary performance requirements.

 

The J2 featured some very modern design choices, including an underslung mid fuselage radiator. (Wikimedia)

However, the J.2 was not the only project of that year, as another design featuring new construction methods was also in the workshop through 1916. The Junkers J.3 would never be completed, but it was the first Junkers project to feature the famous corrugated duralumin skin. Given that it was still a fairly soft material, the bends in the skin would give it the necessary strength to not only act as lifting surfaces, but also structurally reinforce the entire structure by taking shear forces. It would also use a new tubular framework for the wings, built up around a set of stronger tubular spars. While this aircraft would never be finished, these new features would be carried over into the firm’s next design, which would prove to be its first major success.

Reconnaissance under fire

By the end of 1916, not only had the war on the Western front grown into a vicious battle for trench lines between an unsurvivable no man’s land, but aircraft had been proven to be an essential means of understanding the depth of this new and horrible form of warfare. Enemy trenches could only be surveyed from high ground, vulnerable to enemy fire, and the build up of forces were completely hidden from their traditional opponent, cavalry. Aerial reconnaissance thus became invaluable in mapping out labyrinthine trenchworks, finding the positions of enemy guns, and observing the movements of the enemy away from the front lines. Two-seater recon planes were adopted, and fighters were later developed to shoot them down and seize control of vital airspace, but through 1916 the offensive use of aircraft began in earnest. While a canvas biplane had no hope of attacking reinforced trench lines, unable to resist machine gun fire, they could attack enemy infantry at the foremost positions or as they moved through no-man’s land.

While Germany had employed ground attack squadrons in early 1916, it was the use of British infantry contact patrols using fighters and two-seaters through the battle of the Somme that spurred them to develop these tactics further. Moreover, they wanted specialized infantry harassment aircraft beyond their unmodified two-seater biplanes. Losses among these units were high, and the Idflieg, or the Inspector of Aviation forces, produced specifications for a specialized Infantry aircraft. This new plane was to be equipped with armor plate which would enclose the pilot, gunner, engine, and fuel stores with a minimum thickness of 5mm. They were also given a low minimum ceiling of 1500 meters, given they were designed for ground attack and low level reconnaissance. To make a note, this series was designated the I-type, but given the older German writing of I, it appeared as a J, and this series has subsequently been noted as the J type ever since.

The Halberstadt CL.II was built for reconnaissance and ground attack, though its wooden construction left it vulnerable to ground fire. (The Great War Channel)

Albatros and AEG both promised armored versions of their successful C.XII and C.IV models respectively, but Junkers approached the specification with a new concept entirely. While he was forced to build a biplane according to the Idflieg’s specifications, he was still granted considerable leeway with the design. Junkers himself would not be as hands on with this project as he had been the J.1 .2 and .3, over its necessity of being a biplane, so instead he elected to put the project in the hands of a team of engineers. The design of the Junkers J 4, would be managed by Dr-Ing Otto Mader, along with teams headed by the engineers Otto Reuter, Hans Steudel, and Franz Brandenburg.

While it was a biplane, the new aircraft still drew from the experiences and design philosophy of previous projects. Its wings featured corrugated duralumin skin over the multi-sparred, tubular duralumin framework and were in a sesquiplane arrangement, with the lower wing being significantly smaller in length and chord than top. They were connected by an inner set of struts, but being self supporting, they needed no bracing wires. Its armor protection was comprehensive, half of the fuselage consisted of an octagonal steel compartment which contained the engine, pilot, gunner, and fuel. Rear of this armored section was a tubular frame which ended with a conventional tail section. Unlike Junkers’ earlier underpowered efforts, this new plane was equipped with a significantly more powerful 200hp Benz B.IVa straight six engine. This model was among the more powerful aviation engines in German service, excluding those built for airships.

The massive Junkers J.I featured heavy armor protection and structurally redundant wings, it was exceptionally resistant to small arms fire. (SDASM)

Three prototypes were ordered on November 3rd 1916, and delivered the following January as J.425/17, 426/17, and 427/17. On the 28th, one prototype with the 200hp Benz IVa was flown by German officer Arved von Schmidt without armor plate for testing. Taking off from snow 20 cm deep, Schmitt took the plane up to 250 meters and reached a speed of 155 km/h, finding that the aircraft was stable, if tail heavy. The demonstration was impressive enough to get an order for 100 planes on February 19, 1917. The Junkers J 4 was thus accepted into service as the Junkers J.I, under the German Air Service’s designation system. Some minor changes before mass production included a redesigned vertical stabilizer, overhung balanced ailerons, and a balanced rudder.

Given that the workshops at Dessau had yet to receive an order for a mass produced aircraft, building the new planes at a fast enough rate proved difficult. There were two major challenges, first was that while Prof. Junkers was a brilliant inventor, he and his firm were fairly inexperienced when it came to aircraft production, and second, given that this was the first mass produced-all metal aircraft, the methods of mass producing an all metal plane would be learned with it. The Army foresaw this becoming an issue and brought in Anthony Fokker, a master in aircraft production, in order to set up an aircraft factory alongside Junker and Co. in Dessau. The new Junkers Fokker Werke AG. was thus established to build a completely new production line for planes, as subcontractors could not be used to build components, as was the case for wooden planes. The arrangement worked well, with Junkers and Co. engaged in the experimental work and providing designs, while JFA handled the job of meeting the production orders, which in total amounted to 350 planes. In spite of the new facilities, bottlenecking, and the loss of one of the armor plate manufacturers to flooding, would restrict the number of planes built to far below this number.

The Flying Tank

The first J.I to see service was the first off the production line, no. 100/17, which was sent to the front in August of 1917 where it served with the Flieger-Abteilug 19. On one of its first missions, the unit commander flew the plane on a low altitude recon mission near Ypres, Belgium, and found that the plane was not only faster and better handling than the Albatros and AEG J types, but that he had received 11 hits to his aircraft, without issue. FA-19 continued to fly the aircraft, and on one occasion on September 23, 100/17 was hit 85 times, without suffering serious damage.

 

By October, the unit had accumulated enough experience to give an account on using the aircraft. In addition to its excellent protection from bullets and shrapnel, the plane could be flown confidently in weather that kept all others grounded, and it had an excellent glide ratio, which meant that in the event of engine failure, a pilot could still glide his plane back over to friendly lines and evade capture. However, it also required a long take off run and it had a higher landing speed than most aircraft. Luckily, these were issues that could be solved by instruction from more experienced pilots, and practice. Overall, the Junkers J.I proved to be an excellent aircraft from the appraisal of FA 19.

After its front line trials with FA 19, the Junkers J.I would begin to be distributed to the Schutzenstaffel, or protection flight units, whose job was to patrol the area between the opposing trench lines. This entailed a variety of missions from escorting two-seater recon aircraft to ground attack missions, with each unit consisting of some sixty seven men and six planes. Up until 1918, this role was filled by more versatile two seater aircraft like the Halberstadt CL.II, but come the winter of 1917, a small number of armored J type planes were entering service with them. This included four Junkers J.Is issued to the Schusta in December of 1917, a number which would grow to sixty by August of the following year, alongside 186 armored planes of other manufacturers. The nature of this change was revealed more fully when the Schusta were redesigned Schlachtstaffel, or attack flights, during the March offensive, as their escort role was dropped.

The Junkers J.I was used as a support aircraft whose role was primarily reconnaissance and infantry liaison work. The rear seat was equipped with a 7.62mm machine gun, and occasionally a 20mm Becker auto cannon in service, but ground attack was a secondary use of the aircraft. Its most important job was to survey areas of the battlefield that were in contention, to take photographs of bottlenecks in the terrain, or send reports of urgent developments directly to divisional HQ’s via wireless telegraph. First and foremost, the mission of J.I crews was to assist in communicating the state of the changing battlefield, an important task as in the spring of 1918 the war was again entering a mobile phase. Likewise, messages were also delivered from the HQ to the frontlines, as the telegraph wires were easily knocked out by artillery fire. Aircraft were directed by signalers, attached to infantry brigades, by the use of flares, lamps, and fabric strips to mark the position of friendly forces and enemy positions. Working with the signallers, the J.I’s crews could deliver messages to forward commanders from their headquarters, as well as supplies, like food and ammunition, to difficult to reach frontline positions.

A J.I crew prepares to drop canned food, water, and bread to a forward unit, an often overlooked task. While supply runners may not have been able to reach certain positions in daylight, crews like these could drop supplies from behind their aircraft’s armor plate. (SDASM)

In an offensive role, the most powerful tool accorded to the plane was its radio, which could be used to direct artillery, and could also be used to direct the plane to tenuous areas of the frontline to render support directly. While it was typically the job of the Schlachtstaffel to render support near friendly forces, and harass traffic behind the enemy lines, the lack of a bomb load and a standardized forward gun arrangement meant the offensive capabilities of the Junkers J.I were quite limited. The observer/gunner could engage using the mounted machine gun, but they were totally overshadowed by the lighter, unarmored two-seaters, which carried nose mounted guns and could be fitted with bomb racks.

In service, crews rendered excellent service with these aircraft, and many swore by them. One Lieutenant Wagner of Flieger Abteilung 268 flew a mission on March 28th, at an altitude of 80m over the front. During the mission, his observer was wounded, and his own helmet was shot through, but his plane, No. 128 received over 100 hits which did nothing to impede it. The Leutenant was amazed by this, as he’d overflown the enemy trenches, something that would have been suicidal in nearly any other aircraft. These encounters were fairly frequent, as one of the main tasks of the Junkers J.I units was to overfly the enemy trenches and locate the position and size of enemy reserves.

 

Ground crew maneuver a J.I in a photo for publication. (Wingnut Wings)

The Junkers J.I was considered totally unsuitable in aerial combat, given its low speed and ponderous maneuverability. Though, there is one known encounter between an American fighter and a Junkers J.I, which might very well be the only air engagement with the rare armored scout. Major Charles Biddle of the USAS 103rd Squadron, was flying his Spad XIII on May 15, 1918. While returning towards his side of the lines, after a weapon malfunction ruined an interception of a German recon plane, he encountered a ‘peculiar two seater’. Coming down to take a look, it lacked the hallmarks of most German planes of its type, but its unmistakable crosses marked it as an enemy plane. He also noted its extremely low speed, calling it ‘the slowest bus you ever saw’ and remarked he made two miles for its one. The Major dove on the plane and took up position fifty yards below its tail, then he made a mistake. He pulled up to take a shot at the Junkers, but he had misjudged the distance and ended up in the propeller wash of the German two-seater, shaking his aircraft and throwing off his aim. He dove to escape the view of the enemy gunner, but now was underneath his target. The German pilot then began to turn to bring the Spad into view of his gunner, and after several swerves to try to shake the American from beneath his plane, he succeeded. Now out of the Junker’s blind spot, Major Biddle was now the target of the gunner who, and in the words of the Major himself found himself in the crosshairs of “some of the quickest and most accurate bit of shooting that I had come up against”. The shot put a hole through the Spad’s radial engine and into Biddle’s left leg above the knee. He dove, to escape the gunner and head for friendly lines, wounded and with his engine failing. He landed in a field of shell craters, his plane turning over, in a fortunately escapable wreck. Major Biddle was likely the opponent of pilot Feldwebel Ernst Schafer, and Lieutenant Wilhelm Paul Schriber of Flieger Abteilung (A) 221, who subsequently overflew the plane and took photographs of their victory.

Construction

The all metal Junkers J.I used duralumin and steel for nearly everything but the engine braces and rear fuselage skin. (Peter M. Bowers via Fredrick Johnson)

The Junkers J.I was an all metal aircraft built from nickel-steel and duralumin. The forward fuselage was an octagonal compartment built from steel with an armor thickness of 5mm, though late production aircraft used a thickness of 3.5mm for their sides, and 6mm for the rear. The armor was impervious to small arms fire, and enabled the aircraft to overfly enemy trench lines at low altitude. The entire forward fuselage was built up around four large duralumin longerons, and joined to the rearward section, which had a tubular construction. The rear section was skinned with fabric, though the tail section was of duralumin construction with the rudder initially being fabric skinned, before it too was changed to corrugated duralumin later in production. Some very late examples of this aircraft had a corrugated aluminum skin over the rear fuselage, though these do not seem to have been delivered to the Army. The fuselage was joined to the wings by a series of steel tubes covered with protective aluminum fairings, and sat atop the lower wing. The undercarriage of the aircraft featured a conventional construction of two vees, connected to the axle through a shock absorber. The axel was a steel tube 9ft long, with it and the other structural elements being covered by aluminum fairings. The tail skid was of a simple wood construction.

 

The armored fuselage was manufactured at the Dillinger Panzerwerk from high tempered steel. (Flight)

The aircraft had a sesquiplane wing configuration with the upper wing having a span approximately 38% longer than the lower. The fine details are disputed, but the upper wing had a span of some 16m and a chord of 2.50/2.25m, the lower a span of some 6m and a chord of 1.50/1.08. The upper wing had a set of balanced, hanging ailerons. Both the upper and lower wings were built in three sections, consisting of an inner panel which was attached via steel tube struts to the fuselage, and two outer panels. The wings were built around multiple tubular spars made from 40mm tubular duralumin, with the upper wing possessing ten, the lower only five. These spars ran the length of the wing and were connected to a number of steel brackets which connected them to a framework of smaller tubes, which joined the spars and stiffened the wing. This design gave the wing both incredible strength, which needed no structural struts or bracing wires, and was extremely resilient to gun fire, as only when many of the brackets or spars were damaged would the wing become compromised. The wings were skinned in .3mm duralumin sheets which were corrugated to strengthen them, as the duralumin alloy was very soft, and was used as a structural element of the wing which bore shear forces. One aircraft, no. 749/18, was equipped with long span upper wings to lower the take off run of the aircraft, the modification did not make it into production.

 

The upper wing had ten tubular spars, not counting the aileron rod, and damage to any one of them was mitigated by others and the web of brackets through the wing. (Flight)

The control system of the aircraft also represented another departure from the conventional methods, eschewing the traditional wire control system for a more resilient push-rod system. The control systems were a duralumin stick and foot pedals for the rudders. The ailerons spanned the entirety of the outer wing panels and were connected to an aileron tube which ran parallel with the structural spars, which was articulated by linkages to the central control stick. The elevators had exterior stranded wires, which were articulated by the push rod system within the fuselage of the aircraft. The rudder operated much the same way. The cockpit furnishings were basic and the instrumentation consisted of a tachometer and fuel gauge, with a compass mounted on the wing.

The Junkers J.I was equipped with a 200 hp straight 6, Benz IVa engine. The similar 230 hp model had a dry weight of 370kg, a bore of 145mm, a stroke of 190mm, and a compression ratio of 4.91:1. It measured 1,990mm long, had a width of 530mm, and was 1150mm tall. It was water cooled, with the radiator mounted above the engine along the upper wing, its slats controlled by means of a lever above the cockpit. The fuel tank was a 98 liter seat-tank which took the place of the pilot’s typically wicker chair. It was made of sheet brass and had a channel through the back for the control rods for the tail section of the aircraft. It was divided into two sections so that a single bullet hole wouldn’t drain the entire tank. A pump drew fuel from this tank and delivered it to the gravity feed tank in the upper wing, if the pump broke the system could be driven by hand. A 38 liter oil tank was located behind the instrument panel. The engine was fitted with a 2.9m wooden propeller with a pitch of 1.9m. They were manufactured by Axial-Propeller Werke of Berlin and were issued with prop-spinners. The engine bay had two articulated panels which swung rearward to allow easy access to the Benz IVa engine, which was mounted atop two wooden engine bearers made from solid ash.

 

A Telefunken radio set, amplifier, and assorted gear. (stone vintage radio)

The plane could carry a variety of equipment for its missions, though these were mostly commonly a camera, and a wireless telegraph set. The observer, who was also the commander of the aircraft, operated both of these. The camera was a separate piece of equipment carried into and out of the aircraft by the observer and set within a built-in mount. This was set in the fuselage behind the armored section and accessible through a sliding sheet metal panel. The telegraph set was installed within the armored fuselage. Built by Telefunken, the W.T. was standardized across the service. It consisted of a sturdy, protected case and a 37 m aerial, with the alternative Huth made transmitter having a 38 m length.

In regular service, the aircraft carried no forward mounting weapons and carried only a rear mounted gun within a swivel mount, which was set within a turning wheel around the observer’s seat. This allowed him to traverse the gun 180 degrees and take aim at targets above and below the aircraft. This was a largely defensive weapon, but could also be used in a limited anti-infantry role. The gun was either a parabellum MG 14 or, more rarely, a Becker 20 mm autocannon.

 

An observer with an MG 14. Like the British Vickers gun, it was a redesigned Maxim variant that reduced the size of the weapon significantly. (airwar.ru)

The MG 14 was a 7.62mm machine gun derived from the common MG 08 in service with the German army. However, it was much more compact as the toggle-lock mechanism was reversed to a downwards action, it used an internal spring, and the ejection system was made to drop casings out the bottom of the receiver rather than the front. The result was that the receiver was narrower and slimmer compared to the more cumbersome infantry machine gun. They were also equipped with a buttsock and pistol grip, with some examples being equipped with an Oigee magnified reflector gunsight. The water cooling system was not used, and the jacket was perforated to reduce weight. The gun was fed from a cloth ammunition belt which was spooled within a metal drum, with one carried on the weapon and two in reserve. It had an adjustable rate of fire between 600-700 rounds per minute. An experimental armament of two fixed, downward facing machine guns for trench strafing was installed on one aircraft, but was not used in service.

A very advanced weapon for its day, the Becker autocannon would go on to influence the development of the 20mm Oerlikon gun. (mnemonic-shapeways)

The 2cm Becker autocannon was a powerful, if cumbersome weapon. It operated on API blowback and was loaded with ten and fifteen round box magazines. Ammunition loads could consist of solid shot or high explosive shells, which could prove absolutely devastating against canvas biplanes and effective at harassing infantry. It did however have a relatively low muzzle velocity of 490m/s and a slow rate of fire, between 250 and 300 rpm, depending on the manufacturer. These were installed aboard a few Junkers J.Is, but the machine gun armament was far more common.

Each plane came with a repair kit for surface damage and the following spare parts: 1 undercarriage axle, 2 spare wheels without tires, 1 tail skid with spring, 1 complete set of structural struts and associated connecting parts, 2 trestles, 1 lifting jack, 1 set of tools, and riveting materials.

Flying and Servicing

The Junkers J.I was a ponderous, but steady aircraft to fly. Its top speed was decent for a two-seater, at 145 km/h, but its climb rate was extremely low. It took 77 minutes to reach 3km, though in service it typically operated below 1km, which only took 12 minutes to reach. Coupled with its wide turning circle, the plane earned itself nicknames like the flying ‘Tank’ or ‘Mobelwagen’, or translated, moving van. Given its low speed, it was typically given escorts. Its controls were responsive, though were different enough from its contemporaries to need some practice getting used to. The stick for instance could become shaky and uncomfortable to use if inputs were harsh and jerky. Its landing speed was also notably high, and it required a longer run for take off and landing, preferably made on compacted ground. These issues aside, most pilots were fairly confident in the aircraft, and when flown it was a very stable, especially in the wind and rain, which kept everything else grounded.

 

The Junkers J.I was often a difficult adjustment for pilots, though its stable handling characteristics and robust construction made for a safe re-learning period. (Wingnut Wings)

Crewmen were also very appreciative of the incredible amount of protection the aircraft afforded, allowing missions that would have otherwise been considered suicidal to be completed with a high level of confidence. Not only were all of the critical components of the aircraft all located within a nearly impervious armored compartment, but the wings were extremely durable and unlikely to fail even when struck continuously by machine gun fire. Perhaps best of all, the risk of fire damage was extremely low, and the fire resistant construction would give the pilot time to set the plane down. When all else did fail, and the engine gave out, the aircraft had a good glide ratio, and despite its weight, it could travel some distance without power, allowing the crew to cross back to friendly lines, or look for a safe place to ditch. Overall, the Junkers J.I was in all likelihood, the most durable aircraft to see action during the Great War, and certainly the best of the armored J type aircraft in service with the German Luftstreitkrafte. In the end, only one confirmed combat loss was noted in over its one year of service, performing one of the most dangerous missions.

 

A high landing speed and a need for compact ground meant that numerous J.I’s that  were taken out of action in accidents like these. Few were serious and the planes were typically sent back to depots for repair. (Wingnut Wings)

Its metal construction also gave a number of advantages in the field. Most convenient of all was the fact that it could be stored outside in bad weather. While wood and canvas could not be allowed to stay wet and needed shelter from the rain, a Junkers J.I only needed to have its engine and crew compartments covered. The plane was also designed from the outset to be easily transportable, the wings, tail section, and struts could be easily decoupled and placed alongside the fuselage, allowing it to easily fit in a railcar or trailer. The lack of bracing wires made this easy, and also removed a great deal of the maintenance work. Basic repair tasks were fairly simple, and every plane came with a patching kit that made combat repairs easy, but specialized training was needed for larger components. Extensive repairs usually required the planes to be sent to depots where specialists could work on them, and was usually done in the case of extensive damage to the wings or fuselage. Larger single-piece components, like the struts, were simply replaced with spares if damaged.

Conclusion

The Junkers J.I proved to be a pivotal design in airplane development, as it not only introduced to the world a mass produced all-metal plane, but it also incorporated so many other innovations, such as its cantilevered wings and use of corrugated duralumin. They would provide a practically indestructible plane to what would have been very vulnerable crews, and in the years to come, these features would put Junkers well ahead in the civil air industry.

Junkers J.I
Engine Benz BIVa
Engine Maximum Output 200hp
Empty Weight 1766kg
Combat Load 410kg
Maximum Speed 155 m/h
Combat Ceiling 3km (operational)
Armament 1xMG 14 or 1 x 2 cm Becker Autocannon
Crew 1x observer 1x pilot
Length 9.20m
Height 3.45m
Wingspan 16m
Wing Area 50.84m

Illustrations

J.100/17 was the first to enter service with the Army testing it in frontline use in the Autumn of 1917.
As the Junkers armored planes began to enter more widespread service, crews began to fashion their own camouflage schemes. Mauve stripes became a fairly common pattern among these aircraft. Flieger-Abteilung 17, 1918.
Late production aircraft had their fabric skinned vertical stabilizers and tail sections replaced with duralumin sheeting. The fabric sections of the aircraft often went unpainted, and left in the dyed lozenge camo patterns it was delivered with. Unknown unit, based at Villiers de Chevres, 1918.

Credits

Written and edited by Henry H.

Illustrated by Arte Belico

Sources

Primary:

Instruction Manual for Junk. J. I Armored Biplane. Junkers-Fokker-Werke A.G. Dessau. Translated and reproduced in Flight The Aircraft Engineer & Airships Vol. 12. 1920.

Report on the Junker (sic) Armoured Two Seater Biplane, Type J.1*. Ministry of Munitions. Reproduced in Flight The Aircraft Engineer & Airships Vol. 12. 1920.

Secondary:

Junkers Aircraft of WWI Vol 1 Junkers J.1-J.4. Owens, Colin A. Aeronaut Books. 2018.

Junkers J.I. Grosz PM. Albatros Productions. 1993.

Junkers 52 A History 1930-1945. Forsyth, Robert & Creek, Eddie J. Crecy Publishing 2014.

German Observer’s Guns. Woodman, Harry. Albatros Productions 2001.

German Air Forces 1914-1918. Sumner, Ian. Osprey Publishing Ltd. 2005.

Douglas F3D, F-10 Skyknight

United States of America (1951)

Nightfighter & Electronic Warfare Aircraft: 265 built

Skyknights on the muddy ground of K-6, Korea. (USAG Humphreys)

Designed after the Second World War, the Douglas Skyknight was meant to be the defender of the American carrier group after dark. The ambitious design sought to use all of the lessons learned from night fighter design and tactics in the Second World War, and produced the first specialized all-weather jet fighter. While it would prove too cumbersome for use on the smaller WWII era fleet carriers, the Skyknight would prove to be an exceptional nightfighter when disembarked during its combat debut in the Korean war. Yet beyond the conflict, and entering rapid obsolescence as a fighter in the 1950s, the Skyknight would prove itself to be an able electronic warfare aircraft and a pioneering aircraft in its field.

American Night Fighter Experiences in WWII

The more advanced, radar equipped night fighter of the Second World War was an ad-hoc creation which combined state of the art airborne detection systems with often pre-existing fighter designs. The resultant creation was an interceptor capable of bringing down enemy aircraft at night, or in very poor weather. While they carried their own radars, the limits of their range required they be directed by ground controllers into the path of their target. Alternatively, they could be tasked with offensive patrols to harass the enemy over their own airfields or carry out ground attack missions. In either case, sorties were demanding, with the crews of these aircraft having to endure patrols of several hours, flying almost entirely by instruments, and occasionally in extreme weather conditions. Even without the dangers of aerial combat in the dark, flying these aircraft was often exhausting and dangerous work. Vertigo was as deadly an opponent as any enemy they might encounter. Unsurprisingly, the best qualities that these aircraft could possess were straightforward flying characteristics, like good handling and stability. A good night fighter needed to be uncomplicated, and forgiving in how it flew.

The P-61 was a massive, but fairly short ranged night fighter with a mixed service record between the European and Pacific theaters. (san diego air and space museum)

The American nightfighters of the Second World War can largely be broken down into two groups. These were the heavier, twin engine, land based types in use with the Army Air Force, and the lighter carrier-embarked forces of the Navy. The Air Force’s principle nightfighter was the Northrop P-61 Black Widow, a purpose built, if somewhat over-engineered design that saw use across Western Europe and the Pacific. The design was cutting edge, featuring a state of the art airborne intercept radar system, and an impressive, if totally unnecessary, remote controlled gun turret. It flew exceptionally well, was nimble beyond what its size would suggest, and was fast enough to catch all but high flying, fast recon aircraft. Yet the design had two serious limitations. Foremost was its disappointing endurance, as in spite of its size, its limited fuel capacity and massive Pratt and Whitney R-2800 engines meant it had a range comparable to many single engine fighters. This was partially resolved by the installation of wing pylons which could fit either fuel tanks or bombs, though having to choose between ordinance or range imposed significant mission limitations. Less serious was its poor crew layout. As designed, the pilot and radar operator sat at opposite ends of the fuselage, hampering communication and, in the event of an accident, the loss of the intercom completely isolated the radar operator from the other two crewmembers. This limitation was overcome by the crews of the 425th Night Fighter Squadron, who moved the radar operator’s equipment to the gunner’s position. However, this modification was almost entirely limited to the European theater.

While the P-61 proved a capable night fighter, and an excellent all weather ground attack aircraft, there was much to be learned from the Mosquito Night Fighter Mk. 30’s that were made available to American crews near the end of the war. The Mosquito featured a side-by-side pilot and radar operator arrangement, and a large internal fuel capacity that gave it excellent range without having to install external fuel tanks. While it was less maneuverable, it was arguably the best night fighter of the war, capable of pursuing targets over long distances and attacking enemy rear line airfields at night, without having to sacrifice ordinance for range.

In all, the experiences of the P-61 crews were mixed. In Europe, they provided good night cover for the Army Corps they were assigned to, and during the siege of Bastogne, they were among the only fighters providing protection and support to the beleaguered Airborne forces in the city, when poor weather kept all but a handful of aircraft grounded. In the Pacific, they were less successful, particularly towards the end of the war. During the battle for the Philippines, they often struggled to deal with the swarms of Japanese fighter bombers that flew dawn and dusk attack missions. The P-61’s were never designed or intended to defend against such forces, and found them a challenge to bring down. Where in Europe they gained the personal thanks of the commanding officer of the 101st Airborne Division within Bastogne, they were the target of General MacArthur’s personal frustrations as his beachheads were continually harassed by Japanese forces.

Small composite units of F6F and F4U Corsairs operated aboard US carriers for night defense. They proved just as capable when deployed ashore. (wikimedia)

In contrast to purpose built P-61, the night fighters of the US Navy were fairly simple conversions of existing fighter planes converted to serve as a defense for carriers at night. Variants of the F5F Hellcat and F4U Corsair were fitted with small, wing mounted radar sets to allow them to track and engage targets at night or in poor weather at the direction of ground controllers. They were far simpler aircraft, and generally were tied down more heavily to their ground controllers as a result of their shorter range, and simpler radar systems. Within the fleet, the duty of these night fighters was to contend with enemy aircraft that attempted to attack naval vessels under the cover of darkness. When assigned to land based Marine corps aviation, they were typically charged with the protection of amphibious operations and providing air cover for important installations. In both cases, these light night fighters proved very successful, and in the case of the Philippines, F6F Hellcat night fighters ended up replacing P-61’s as the defenders of the beach head. However, the limitations of the single engine fighters left the navy wanting something more. The Hellcat and Corsair night fighters were fast, but they had a fairly short range, and lacked a dedicated radar operator. The benefit of the heavier night fighter was its ability to more easily re-acquire targets which may have evaded the first attack and longer endurance, which allowed it to pursue and catch fleeing targets over an extended chase.

The new F7F-N was hoped to be the ultimate carrier based nightfighter of the Second World War, carrying both a second crewman to operate radar and navigation systems, and having a significantly better range. However, it was not to see use during the war, it was too large, and it was soon to be obsolete. The piston engine was being superseded by the jet turbine, and the carrier air wing of the future would soon need an aircraft to contend with threats far faster than any of their existing fighters.

Douglas’ Dark Knight

In August of 1945, at the very end of the Second World War, the Navy’s aviation bureau set its requirements for a new carrier based, jet night fighter. It called for a top speed of 500 mph (805 km/h), a service ceiling of up to an altitude of 40,000 ft (12,192 m), and a 125 mile (201 km) radar intercept range. Beyond its performance requirements, it was to also carry a pressurized cabin with temperature controls, and a robust set of de-icing equipment. Four companies presented bids, these being Douglas, Curtiss, Grumman, and Fleetwing, with preliminary design work beginning in October. By April of the following year, the contest was over, with only Douglas’ proposal receiving a letter of intent, the resources to construct three prototypes, and ground testing materials. Its daylight counterpart was to be the Grumman F9F Panther, with the two fighters being poised to propel the US carrier forces into the jet age.

Designer Ed Heinemann with his 88 Oldsmobile alongside the Skyknight. (smithsonian)

The design dubbed ‘Skyknight’ incorporated many of the lessons learned from the Second World War. The aircraft’s chief designer was the prolific Ed Heinemann, who designed some 20 aircraft through a very productive career. Some of his most notable creations were the venerable SBD Dauntless, AD Skyraider, and A-4 Skyhawk. His Skyknight featured a cutting edge search radar which was operated by a crewmember seated beside the pilot, allowing for easier communication. The radar was also to feature a fire control system which gave the pilot an accurate lead on his target, allowing him to engage maneuvering targets and those that were not visible to him. They attempted to fully resolve the drawbacks of the Black Widow by installing large internal fuel stores, but the high fuel consumption of the turbojet engines meant the aircraft had comparable range to most other jet fighters of the era. Beyond its combat ability, it was to be a very straightforward aircraft to fly, with stability at both extremes of its speed limits. Its only eccentricity was that it had an ejection chute as a means of crewmen to escape the aircraft in an emergency. Altogether, it was a conventional, honest aircraft that flew well.

The first XF3D-1 prototype was flown by test pilot Russ Thaw on March 23, 1948, with the second flight following in June, and the final in October. Apart from basic safety and performance tests, the aircraft was flown in mock intercepts against single seat jet fighters. Even with their World War II era SCR 720 radar, they easily managed 85 mile (136 km) intercepts with GCI support. The Air Force also conducted tests on the aircraft, and inquired about installing the fighters with afterburning engines, but declined and instead developed the all-weather F-89 Scorpion.

The Skyknight was a remarkably stable and maneuverable aircraft. (aerocorner)

After satisfactory land based flight testing, the Skyknight received a production contract. The F3D-1 would replace the prototype Westinghouse J-34-WE-22 engines with more powerful WE-38’s, and the WWII era SCR-720 radar system was replaced by the new AN/APQ-35, a change made in the third prototype. The new radar boasted a much longer effective range, and was the first airborne radar with a lock-on feature, which allowed for the continuous, automatic tracking of a radar contact. Modifications continued to be made on the F3D-1’s as the engines were again changed to the J34-WE-34’s and their plastic-glass nosecones were switched to fiberglass.

The Skyknight was built around the concept of the heavy night fighter, and was thus at the limits of how large a carrier-borne aircraft could be. In an age where carriers were originally designed for single-engined, piston aircraft, the F3D-1 would prove rather troublesome. The comparatively massive Skyknight was difficult for carrier deck crews to maneuver about the ship, and prepare it for launch. The bridle, which connected the nosewheel to the catapult, needed to be significantly stronger than those used for other navy fighters, and the proximity of the wheel to the engine intakes required a greater level of safety, and these precautions lengthened launch procedures. The landing gear shock absorbers too were also judged inadequate, as the plane bounced excessively during arrested recovery, and high vibrations were noted. This was particularly worrying, as the Skyknight’s radar system used vacuum tubes, and was quite fragile. These, and other problems, saw the F3D rated for marginal daylight use and was prohibited from launching and recovering at night.

Another major challenge was to be found in training programs, both for pilots and radar operators. The training program for radar operators was notably lacking, and provided no specialized training for the complex radar systems aboard the Skyknight. A result of an underappreciation for how sophisticated the job was, and a lack of funding.

The Skyknight’s were significantly larger than all previous carrier borne aircraft. This often proved challenging on carriers designed for single engine piston aircraft. (Naval Air Museum)

Landing issues were resolved in the subsequent, and final production model, the F3D-2. The new model was designed primarily to get larger, more powerful engines into the aircraft, though the J46 engine they were slated to receive never materialized. However, they still represented a serious improvement over the first model, as they were equipped with an improved version of the J34 engine, an autopilot, gun laying radar, tail warning radar, wing spoilers to increase the aircraft’s roll rate, and they received the modifications that would get them cleared for their full use aboard aircraft carriers. They soon succeeded the small number of F3D-1’s built, with the first aircraft being flown in February 1951.

The first of the new F3D-1 Skyknights took flight on February 13th of 1950, with the Navy accepting the first deliveries, which were then turned over to Composite Squadron VC-3 in December of the same year. One of Douglas’s test pilots, LaVerne Brown, would give the Naval Aviators an introduction to the aircraft. The Skyknight would fully enter service in February, with the aviators familiarizing themselves with the new aircraft, and being bolstered by another combat squadron, VC-4. The new squadron would be the only one to actually be deployed aboard carriers.

They would not prove ideal. The dimensions of the aircraft proved problematic, being far larger than what the deck crews were accustomed to, and they were occasionally mishandled, resulting in minor damage. The weight of the aircraft also complicated the use of the carrier’s catapults. The H-8 hydraulic launching system needed to be used close to its maximum power setting to launch the Skyknight, and if the bridle was not well connected to the aircraft, the catapult hook could break free, and be sent hurtling toward the end of the track at the bow of the ship. The collision would necessitate a lengthy repair, and during their deployment aboard the USS Lake Champlain, it happened twice, much to the frustration of all aboard. Lastly, the low mounting position and slight downward cant of the aircraft’s engines baked the wooden deck of the carriers and had a habit of setting alight any flammable materials which may have leaked from any of the planes or machinery present. These were never large, or particularly dangerous, but any conflagration on the deck was met with an alarm and the entire ship was sent to fire quarters. The Skyknight’s were seen as extremely inconvenient, and frustrating to the carrier’s commanders, who were also very unhappy that the plane had only one, very specialized use. The night fighters and their crews quickly became the black sheep of the air group, even to the other pilots.

The size of the new Skyknight earned it the nickname “Willie the Whale”, with ‘Whale’ slowly overtaking Skyknight as the crew’s preferred moniker. (US Navy)

Pilot’s views of the new aircraft were mixed. The Skyknight was like nothing naval pilots had flown before, and not only because it dwarfed every other plane on the flight deck. It lacked all the familiar trappings of a navy fighter, and if anything it reminded many of them more of a transport aircraft than any fighter they had ever flown. Beyond that, the tandem seating arrangement proved unique, as did the spacious, carpeted, air conditioned canopy equipped with a cigarette lighter and ashtrays. While the Skyknight was not proving to be the answer to after hours protection the US Navy was looking for, many of those assigned to the new jet could not help but be fascinated. They also soon found they could not help but be frustrated when they were asked countless questions about what the plane could not do and the capabilities it did not have. Unlike the other fighters of the US Navy, the Skyknight was not a fighter bomber, but that never stopped the press from asking questions about how many bombs it could carry, or their commanders asking if they could perform daylight strike and patrol missions.

The Skyknight was a bad fit for the carriers of its day. It was far too large and did not have the versatility that might have justified its many inconveniences. It was the bane of the carrier air group, and left deck crews and other pilots irritated, as it meant more work for them. It was a massive, catapult breaking, deck burning, fire starting annoyance that did only one mission. In spite of this, the Skyknight was to become one of the most exceptional aircraft of its day.

While Naval aviation found the Skyknight totally unsuitable for their purposes, the Marine Corps were eager to get ahold of them. The Marines still flew their piston engined Tigercats and Corsairs, and believed wholeheartedly in the two-man nightfighter concept the Navy still was not entirely sold on. As opposed to the Navy, with jet fighters aplenty, the Skyknight represented a massive upgrade for the Marines, who already flew a fair share of oddball planes. It was thus in the Corps that the Skyknight found its new home, and would soon demonstrate itself as an incredible nightfighter.

The Forgotten War

Following the end of the Second World War, the Korean Peninsula was controlled by a combined US-Soviet commission, which eventually saw the creation of two governments on either side of the 38th parallel, the formal boundary for Soviet-American jurisdiction. The American supported Republic of Korea was founded in the South, and the Soviet aligned Democratic People’s Republic of Korea was founded in the North. In spite of what the names might suggest, both regimes were dictatorships, and neither recognized each other’s legitimacy. Clashes occurred at the border, and the DPRK was emboldened when the US and Soviet forces withdrew in 1948. North Korean leader Kim Il Sung was confident his forces could reunite the country in a decisive military campaign, and received permission from Soviet leader Joseph Stalin to launch the invasion. On June 25, 1950, an artillery barrage heralded the start of the war as the DPRK’s forces pushed South, and their marines made landings along the Eastern Coast.

The war would escalate into an international conflict that brought in the Soviet Union, China, and the United States with its many allies under the banner of the newly formed United Nations. The air war over the peninsula was an odd affair, with several of the air forces involved having only recently been formed, and flying a mix of World War II era and modern jet aircraft. The People’s Republic of China had only been founded in 1949, with an airforce so new it had not even been fully organized by the start of the war. With Soviet support, they received training and aircraft, becoming a fully realized military force by the end of the war. The DPRK was likewise supported, and possessed a force of WWII era fighters and ground attack aircraft of Soviet make. The Soviets themselves sent pilots and aircraft, seeing it vital that they gain some experience in what was becoming the first modern air war. They would, however, maintain that they were never directly involved, with their pilots officially flying with the Chinese air force.

The UN Forces would operate an eclectic mix of aircraft. Here an outdated F-80 Starfighter shares the ramp with a modern F-86 Sabre. (National Archive)

The UN forces were backed by the largest airforce in the region, the US Far East Air Force, stationed in Japan. The force mostly operated the then obsolete B-29 and B-26 bombers, and F-80C jet fighters. It was by far the most powerful air force in the region, but unsuited for tactical support missions. The Air Force was supplemented by the US and Royal Navies with their carriers, and later, disembarked Marine aviation forces.

Technologically, the forces involved used both the crudest and most cutting edge equipment available. The Soviet aligned forces were, initially, almost entirely dependent on older WWII era stock, their main fighters being Yak-9Ps and La-9’s until attrition ground them away after several months of fighting. After roughly a year, they began to be replaced by the cutting edge Soviet MiG-15, which allowed North Korean and Chinese pilots to claim a level of parity, even as they were largely overwhelmed over much of the peninsula. The disparity in numbers would force them into a defensive strategy which involved a great deal of night operations, and basing nearly all of their new MiG’s in China, where their airfields could not be stalked by American fighters.

The UN forces flew a bewildering variety of propeller and jet aircraft, especially when compared to Communist forces, who by the middle of the war were flying little else than MiG-15s and light ground attack planes into combat. Once their forces were better established in the theater, American air forces pursued an offensive anti-air campaign over the northern half of the peninsula using their own cutting edge F-86 Sabre, while swarms of piston engined F-51 Mustangs, F4U Corsairs, and new Skyraiders were used for close air support, and massed B-29’s were flown against strategic and tactical targets.

The Soviet MiG-15 proved an incredible upgrade over the outdated Yakovlev piston engined fighters, matched in performance only by the Air Force’s F-86 Sabre. (Museum of the US Air Force)

These strategic raids were much the same as those of the Second World War. The Superfortresses targeted factories, power generating infrastructure, and bridges, though the inaccuracy of their methods left much of the northern half of the peninsula in ruins. In an effort to stop the raids, the Communist forces used their new MiG 15’s as interceptors, and could comfortably attack these formations with their combination of heavy cannons, and near unapproachable speed. Only the less common American F-86 Sabres were fast enough to catch them, and thus any real hope of keeping the B-29’s safe during daylight hours was gone. Their solution was to transition to night bombing, which would eliminate all but a few very specialized Soviet MiG 15 crews from being able to intercept them. This nocturnal shift in the war over the peninsula saw night fighting transitioning from a mostly tactical affair, involving aircraft raiding or defending frontline positions at night, to a strategic one that pitted each side’s most advanced aircraft against one another over control of the northern half of the peninsula.

Sallying Forth

Marine Nightfighter squadron VMF(N)-513 arrived in Korea in August of 1950 with a dozen Corsair night fighters, and a very difficult job to do. The pilots of the ‘Flying Nightmares’ flew night ground attack sorties in their WWII era fighters. After shuffling from airfield-to-airfield as the Chinese army began its southern march, the unit was reinforced by VMF(N)-542, most of which was returning stateside. The Nightmares received new pilots from the retiring squadron, and some twelve heavy F7F Tigercat night fighters. With them came a new job, night interdiction, which proved to be more dangerous, but much more important. The UN forces had air superiority over much of the peninsula, and thus the Communist forces took to moving most of their supplies at night, often in well armed, well protected convoys. For two years, the Nightmares flew some of the most dangerous missions of the war, with 54 aircraft being lost to all causes. It was in June of 1952 that the squadron was resupplied, again given a new aircraft, and a new mission.

The F4U-5N was the most common American night fighter of the early Korean war. They were primarily tasked with night ground attack missions. (Wikimedia)

While they had received planes and pilots from the 542 in-theater, a cadre of that squadron had retrained on the new F3D Skyknight. They would join the Flying Nightmares in June, bringing fifteen new night fighters, and shortly after, retiring the squadron’s Corsairs. As the Skyknight was virtually useless in an air to ground role, their task was to be the escorts for the air force’s B-29 raids over Northern Korea. They would, however, not enter combat for some time, as the cadre had not been equipped with the blast tubes for their 20 mm cannons. Lt. Col. Lambrecht would take charge of the deployed unit, now with 12 aircraft, 3 having been retained in Japan.

The unit would quickly install the tubes after they arrived on August 5th, with the first combat sortie penned for the 7th. It was to be flown by a joint Royal Air Force-USMC crew, with RAF pilot Squadron Leader John Gardener, and Marine radar operator Staff Sergeant Kropp taking the Skyknight up on its first patrol. It was a local patrol mission, and apart from investigating an unidentified IFF emergency code, not much occurred. Over the next several days, more missions were flown, though no enemy aircraft were intercepted. As it was in the Second World War, night intercepts were difficult, and any failures on the part of the ground based radar director, or the RO on the plane, could result in a botched intercept. Even with the new radar, closing with the target was still a challenging affair that tested the pilot and radar operator alike. It was clear that even with new technical advances, bringing down enemies at night would require a mastery of the equipment, and excellent coordination between all parties.

Having been mostly discarded by the Navy, the Skyknight soon found itself among other oddball aircraft in the inventory of the Marine Corps. Unlike the Navy, the Marines were not ones to turn away an offer for new jet fighters. (Smithsonian)

The enemy they chased was typically in one of two groups, either cutting edge MiG 15’s that were usually flown by Soviet pilots, and rarely encountered outside of the North, or very light trainer aircraft flown in a ground attack role. These were usually Yakovlev 18’s, or the exceedingly obsolete wood and fabric Po-2 biplane. Rarely were these attacks very serious, though their frequency earned them the moniker “bed check Charlie”, a title formerly held by Japanese night raiders of the Second World War. The Skyknights rarely encountered the light piston engined planes, and the MiG’s were their primary opponents.

They lacked radar, but the Soviet pilots were well trained in instrument flying and were proficient in ground directed radar intercepts. They were thus reliant on a local radar, and the tell-tale glow of the Skyknight’s turbojet engines to attack them. Their most effective tactic was a trap in which one MiG flew a straight and level course, while a second trailed it at a lower altitude. Should the first plane find itself pursued, the ground radar would warn them to speed up, and direct the second aircraft to climb and attack the pursuing Skyknight. As the American night fighter had a tail radar, it was often forewarned of the approach of the trailing MiG, but on one occasion, the Soviet pilot claimed a victory. The other threat to the Skyknight were radar directed searchlight traps, which disoriented the crew while AAA batteries attempted to bring them down. This proved far less dangerous than the MiGs.

The Skyknight would prove to be one of the only two aircraft to challenge the MiG-15, though unlike the faster Saber, it relied on its sophisticated radar systems to ambush the mostly blind MiGs. (USAG Humphreys)

While the Skyknights of the 513th were working themselves into combat, a pair of incidents would leave a dark mark on some of the unit’s early service. On August the 15th, the Squadron’s CO, Col. Lambrecht disappeared while on patrol from Kusan, and the Corsair sent to search for him failed to identify any wreckage. On the 1st of September, a catastrophic engine failure brought down another Skyknight. Flown by pilot Maj. Harrold Eiland with his RO, MSgt. Alois Motil, the plane’s starboard engine experienced power fluctuations before breaking down. A clanging noise alerted the crew, as the RPM gauge and fire alarms remained steady. Then the port engine failed, and the plane lost all thrust. As the plane was flying out from the airbase, it fell into the sea, and only Motil escaped the crash. A two month investigation grounded the planes until the culprit was found. It proved to be a turbine compressor failure, which sent shattered turbine blades through the fuselage and into the second engine. While local flights were still carried out, combat patrols would not be flown again until October 17th, when armor plates were installed aboard the aircraft.

The Nightmares wasted no time, and once they were airborne again, they took on the job of escorting the Air Force’s bombers under the leadership of Lt. Col. Homer Hutchinson, who succeeded the late commander in early September. He was notably a much more aggressive commander, who tasked his pilots with seeking out enemy road traffic on their return from their escort missions. Their first escort mission was conducted on November 3rd, to cover the areas where the Air Force’s night fighters were not permitted. Their F-94 Starfire carried sensitive equipment, and could not be directed over Communist held territory.

The Skyknight’s escort strategy mirrored the RAF’s nightfighter tactics of the Second World War. Upwards of six fighters were flown on separate tracks to find and bring down the enemy. One group flew barrier patrols between the bombers and known enemy fighter bases, a second group flew with the bomber formation, and the final group flew over the bomber’s target area. A typical escort operation involved nine Skyknights.

The first victory was soon claimed, with Maj William Stratton and RO MSgt Hans Hoglind catching an enemy at 14,000 ft (4267 m). They struck the aircraft with 20 mm cannon fire, hitting the port wing, fuselage, and tail pipe, with the burning plane shortly descending rapidly out of sight. It was claimed as a Yak 15, but declassified Soviet records identify the aircraft as a MiG 15 flown by Capt. V. Vishnyak, who survived and brought the wrecked MiG home. The squadron’s second victory came on the 8th, when Capt. Oliver Davis and his RO Dramus Fessler were vectored on to a target. The enemy noticed them and attempted to evade, though Davis turned with them and fired. Several shots struck the rear of the enemy aircraft, which set fire to its engine, and they saw it lose control, before plummeting to the earth. The plane belonged to Soviet pilot Lt. Ivan Kovalov.

These new victories inspired great confidence after the incidents of the previous Autumn. Now going into winter, the Skyknight crews of the 513th settled into a routine of escort, and offensive patrols. Between November and January, they claimed four enemy jets and were getting a better handle for the ordeal that the escort mission was soon proving to be. The massive number of aircraft airborne, and the limited number of ground directors meant that communications with GCI operators were heavily strained. Coupling that with the task of navigating the predetermined patrol areas for about two hours, it all added up for a demanding job for pilot and RO alike.

In spite of all that, they proved extremely successful. The Skyknight was proving to be an exceptional night fighter, and was conducting patrols over Northern Korea with impunity. The only real threat were MiG traps, which could only be conducted in clear weather, and depended on perfect coordination between radarless planes and their ground controller.

In those first three months, bomber losses fell, and between February and July, no B-29’s would be lost to enemy fighters. The ungainly Skyknight, once considered almost useless by the Navy, was now proving itself indispensable to night operations over Korea.

The Long Haul

The Nightmares would be joined by another Skyknight unit in the Summer of 1953. VC-4, detachment 44N, the ‘Nightcappers’, arrived in Korea aboard the USS Lake Champlain in early June of 1953. The four planes were proving an absolute nuisance to the operation of the carrier, and they were prevented from flying as much as possible. The detachment’s officer, Lt. O’Rourke, would try his best to argue for more flight hours, in order to simply retain their proficiency. They would fruitlessly attempt to fly daylight missions, after the Carrier Air Group commander did everything possible to prevent them from flying at night. The commanders of the carrier wished to be rid of the planes. The Communist air forces lacked the strength to attack an American carrier in daylight hours, much less at night.

K-6 was a perpetually rainy airfield that hosted a mix of Naval Aircraft. (USAG Humphreys)

After being effectively grounded aboard the USS Champlain, O’Rourke successfully petitioned for the unit to be sent ashore to join the Marine aviators. They settled into airfield K-6, alongside the 513th, and were quickly worked into their schedules. Settling in proved a challenge, as they traded their carrier berths for quonsets, at the rainy, muddy airfield outside of Pyeongtaek. They drew Marine fatigues, though rain gear was in high demand and low supply. It rained constantly and the airfield had a permanent muggy atmosphere, which made landing more difficult, and keeping dry an impossibility. The two were combined during the frequent airstrip overruns, when the planes rolled off the tarmac and into the mud. It was rarely a dangerous affair, though it was always a cold and dirty job dragging out the stuck aircraft. The Navy aviators would also soon learn that the Skyknight had been banned from most airfields in Korea, with the exception of emergencies, as its low mounted engines gouged holes in asphalt as easy as it had baked the wooden decks of the carriers.

The culture shock would also require a good deal of adjustment. Whereas the carrier was well regimented and ran with a clean and ordered efficiency, the Marine Corps was a force which took the odds and ends it was given, and made due. Perhaps the best example came down to how to cut the engine tail pipe to size, so as to have the exhaust be the right temperature. If it was too hot, the turbine blades could overheat and break, if it was too cool, it would not produce anywhere near the amount of thrust it should. For the adjustment, the Navy used a prescribed manual for the process, they turned the engine on, checked the temperature with a specialized gauge, turned it off and let it cool, cut a section, and repeated the process for several hours until the numbers matched the manual.

The Marines turned on the engines to full power, and checked the temperature using the cockpit instruments. If it was low, they shut off the engine, and took a pair of large pliers and bent crimps into the hot tailpipe to shrink the diameter of the outlet. They then turned it up again to full power until the temperature was at least 40 degrees above the book’s absolute maximum allowable temperature. With that, they marked a red line at the max and told the pilots not to exceed that unless they absolutely had to. Doing this made their planes some 20 to 30 knots faster than their navy counterparts, regardless of how much rougher they were. It was harder on the blades and tended to scorch the pipes, but O’Rourke felt the extra performance could make the difference when trying to catch MiGs that held a confident speed advantage. This kind of resourcefulness would prove a necessity from operating from K-6, as spare parts were scarce, especially for the aircraft’s fragile, complicated radar systems.

In the end, they came together, and the Navy and Marine Aviators would be fully integrated and billeted together, in the words of O’Rourke with “no bitching”.

Toward Armistice

Reinforced, the 513th continued its job of MiG chasing. Their job remained the same, and they still had the same issues. GCI services were overburdened, and the radar station on Cho-do island missed a good deal of contacts. While on patrol, the long search range of the AN/APQ-35 was particularly useful, and crews reported spotting numerous contacts that the GCI stations never called out. In comparison, the MiG pilots enjoyed excellent radar direction owing to good training, a larger number of ground stations, and a defensive operations which made for easier planning. Their ability to react to the American night fighters led a number of aircrews to believe the MiGs began sporting radar sets, though this was never more than a rumor.

The number of intercepts of MiG 15s declined, though the aggressiveness of the Soviet, and by then some Chinese, pilots remained. They were learning the strengths of the aircraft, primarily its much higher top speed, and the tried and true tactic of diving and staying low so that the plane would become lost in the haze of radar ground returns. While they were getting better at escaping the Skyknights, they lost their chance to chase the bombers. B-29 ‘Double or Nuthin’ was the last to be shot down on the night of January the 29th, with all but one crewman surviving the war.

The final MiG kill likely belonged to a Lt.Jg Bob Bick, who had been determined to claim a MiG since arriving at K-6. He did so with CPO Linton Smith on July 2, after pursuing a contact, firing, and setting it ablaze. His next message to his GCI director was that his aircraft had taken several cannon hits, and Bick’s plane fell off the radar screens at Cho-do. Bick had fallen into a MiG trap, and though he had claimed the bait plane, the trailing MiG had him. In a unit as small as detachment 44N, his loss was felt hard. A second Skyknight failed to return from that patrol area two nights later, though there were no radio communications, or Soviet records, that might suggest a cause.

There was a superstition amongst the 513th with aircraft that bore a 13. Note the mud emblematic of runway overrun. (smithsonian).

Having successfully shot down one of the Skyknights, the Soviet crews felt a burst of enthusiasm and doubled down on the bait tactic. Three or more trailing aircraft replaced the lone tracker, and they flew out more frequently. The bait plane too embraced their role and made themselves as visible as possible. O’Rourke claims to have chased a MiG flashing its navigation lights, and as he closed to ID the plane, his tail radar alerted him to six pursuing fighters. He promptly broke off the engagement. In the last months, they failed to claim any MiGs, but they had completely stopped them from intercepting the B-29’s. In the final tally, the Skyknights claimed six MiG 15’s, and lost one of their own in combat, with another possibly sharing its fate. There were another four losses, attributed to accidents.

A less dangerous, but much more frustrating threat came in the form of the harassment attacks from the so-called ‘night hecklers’. By 1953, these were training aircraft, usually Yak 18’s and the comically outdated Po 2 biplane. Unlike the Yak 9’s and Lavochkin fighters that Chinese and Korean aviators flew earlier in the war, these light aircraft could be flown from pastures, hidden with ease, and could be flown so low that long range radar stations could not detect them. Apart from raising alarms, a number of them carried out a successful strike against UN force fuel reserves at Inchon. They were otherwise a threat only to a good night’s sleep, as their bomb loads were extremely light, and they were not putting their best pilots in these disposable aircraft. In addition to the AAA gun crews who had not had any targets for months, the Navy’s night fighter squadrons were called in to deal with the ‘hecklers’. There was some excitement among the aircrews, as the prospect of a defensive intercept was a new mission.

Excitement soon turned to disappointment. The pilots of the 513th expected calls to scramble and chase down contacts, but what they got were long nights playing cards in their full flight suits in the summer heat. The ‘hecklers’ were undetectable by radar, and there was rarely a forewarning of their attack. The Skyknight itself was also unsuitable for it, as the disparity in speed between the two aircraft meant the pursuer rarely had a chance to fire before they had to break off the attack to avoid collision. The first heckler was shot down in December, brought down by 1Lt. Joseph Corvi and MSgt. Dan George. It was even more notable, as the conditions were blind, and the crew downed the Yak 18 non-visually, using their radar. Apart from another probable kill, there was little luck to be found against ‘bed check Charlie’.

To better deal with them, Corsair and Skyraider night fighters were brought into K-6 from aircraft carrier dettatchements. These aircraft were handier at low speeds and had much better loiter time, so they could stay airborne and search for much longer. When they did pick up the enemy, they could stay on them as they stuck close to the terrain.

As the war came to a close, and an armistice was fast approaching, both sides fought tooth and nail for where the final North-South demarcation would lie. While diplomatic talks were underway at Panmunjom, the Skyknight’s mission soon changed. B-29 escort missions were over, as were patrols over the Yellow sea. They were to patrol the frontline, which proved extremely disappointing to the crews who were accustomed to owning the night skies over Northern Korea. Oddly enough, in the last week of the war, they were also tasked with ground attack missions, a job once reserved for the squadron’s now retired F7F Tigercats.

513th Squadron members alongside an F7F Tigercat and an F3D Skyknight. For a time, the squadron was flying Corsairs, Tigercats, and Skyknights, but by the war’s end, they were a purely jet aircraft operation (Smithsonian)

For the members of the 513th, the war ended at 2200 hours July 27, 1953. They soon transitioned to training operations, and DMZ no-fly line enforcement. This marked the end of the Skyknight’s surprisingly exceptional role as a night fighter. As an aircraft that had failed miserably in its planned purpose, the air crews of the 513th found in it something that could take them deep into enemy territory, and hunt the most dangerous opponent the war had to offer. Of the two aircraft that posed a threat to the MiG-15, one was a brand new, cutting edge interceptor in the form of the F-86 Sabre, and the other was an underpowered night fighter designed weeks after the end of the Second World War. It was a remarkable tool to a squadron that proved itself extremely flexible, flying three aircraft it had no pre-war training with in a damp and unforgiving environment.

Obsolescence and Testing

The Skyknight’s would remain in limited use as fighters after the Korean War, retiring from the role in the mid 1950’s. (US Navy)

The Skyknight was a dated plane even before it saw use in Korea, and by the end of the war, it was totally obsolete. Aeronautics was progressing in leaps and bounds, new fighters were breaking the sound barrier and mounting much more sophisticated radar systems, far better than the then archaic APQ 35. The squadron that had made a name with the Skyknight, VMA-513, dropped its ‘Night’ suffix when it traded its Skyknights for the Douglas Skyray, a supersonic, all weather interceptor. As it was slowly brought out of combat service, some 200 Skyknights were available for new jobs.

This saw an expansion of the Skyknight’s secondary role, flight testing. In addition to general aerodynamic and safety studies, the cavernous sections of the aircraft once occupied by its radar systems could be repurposed to carry equipment for any number of tests. Perhaps the most important of these was for the carrier automatic landing system. The Skyknight was the first aircraft to carry the Bell ALS, and in 1957, one was used to test the system aboard the USS Antietam. The system was designed to help guide an aircraft on the approach within plus or minus thirty feet (9 m) longitudinally, and twenty feet (6 m) vertically, to the arresting wires on the carrier deck. Ironically, an aircraft that proved so terrible for carrier service played a major role in developing one of the most important systems for modern carrier aircraft.

A lone Skyknight prepares to test Bell’s automatic landing system. (Wikimedia)

Another major, if not quite as groundbreaking task the plane received was in testing early air to air missiles. Throughout the fifties, the first practical air to air missiles were introduced, and while they were not mature enough to totally replace guns, the Air Force and Navy pursued them, believing that they soon might. The Skyknight was chosen as the test aircraft for the Sparrow missile program, and while the weapon did mature into one of the most effective air to air weapons of its day, its first iterations were extremely crude. Sparrow I was a beam riding missile which was directed by the aircraft’s radar into the target. To test it, 28 F3D’s, both 1’s and 2’s, were converted into missile carriers, receiving between two and four wing pylons to accommodate the new weapons, and their 20 mm cannons were removed. These aircraft entered limited service with Marine fighter squadrons, and a proposal for an updated design to carry six missiles was introduced. Nothing came of the program, as the missile was incapable of hitting maneuvering targets and was generally unfit for use in combat.

The Skyknight’s tested, and very briefly employed the Sparrow I missile. They proved to be totally unsatisfactory, and the planes were soon relieved of the weapons (tail spin topics)

As important as missiles was the ever evolving field of electronic warfare. It was becoming ever more vital to know the positions of enemy radar installations, communications infrastructure, and, as would become vital later on, surface to air missile systems. The Skyknight was recognized as an ideal candidate for this kind of reconnaissance mission, as the removal of its radar systems left ample space for electronic surveillance equipment and radar jammers. One F3D-2 would be modified in 1955 and equipped with a panoramic surveillance radar, direction finding and analysis equipment, and a pair of 200 watt noise jammers. Two of its cannons were removed, with two remaining to give the aircraft some form of defense and to avoid weight distribution issues. The plane was modified at MCAS El Toro by two electronic warfare veterans, WO Joe Bauher and MSgt. ER Grimes.

While the Skyknight was far too obsolete to be a fighter, its forgiving handling and large electronics bays allowed it to shift effortlessly into the realm of electronic warfare. (aerocorner)

The prototype was soon joined by a second test aircraft and the pair were evaluated and refined at the Naval Ordnance Test Station China Lake, and the White Sands Missile Range. They proved satisfactory and soon orders to convert 35 Skyknights to F3D-2Q, later redesignated EF-10B, electronic surveillance aircraft were approved. The first of the modified aircraft were received at the very end of 1956 and delivered to the Marine squadron VMCJ-3, with additional deliveries being made to VMCJ-1 through -3 in the following years. With its conversion complete, the Skyknight was to begin its second career.

Back in the Saddle

The first new deployment of the EW Skyknight began in July 1958, with VMCJ-3 rebasing to MCAS Iwakuni, Japan. While its original mission was to help with defensive electronic warfare training, it was not long until they were recruited into the Peacetime Aerial Reconnaissance Program, and used as a surveillance tool against the Soviets, Chinese, and DPRK in East Asia. Under the code name ‘Shark Fin’, the Skyknights flew offshore patrols to gather electronic data on radar stations and communication networks. Among the most crucial patrols were those around the Soviet Far East, though their patrols ranged all over the region, with forward deployments spanning from Tainan, Taiwan, to Misawa, in Northern Japan. Their first major find came in 1959, when they were the first to detect a modern Soviet P-12 ‘Spoon Rest A’ early warning radar which was based near Vladivostok.

Most of these patrols were well within international waters, though patrolling aircraft were still sent out to meet them. With the Soviets, it was a nearly carefree affair. While Skyknight and MiG pilots were engaged in a deadly cat and mouse game nearly a decade earlier, they made peaceful, routine intercepts over the Sea of Japan and its neighboring waters. One Captain Chuck Houseman would remember monitoring communications between a MiG pilot and his ground controller. When the fighter pilot asked what to do when the Skyknight’s ECMO began to take photos, his ground controller suggested he smile. On another occasion, in 1965, he flew with external fuel tanks which bore a message which, in Russian, read “JOIN THE US MARINE CORPS”. The joke was not appreciated in the higher echelons of his command, and the tank was soon painted over after they received complaints from the NSA. Soviet encounters were usually without issue, though the Skyknights would often try to avoid them by flying out over open waters and, with their twin 300 gallon (1135 liter) external fuel tanks, wait until the MiG’s ran low on fuel, before resuming their patrol.

Marine EF-10’s on the tarmac. They would convert 35 Whales for EW work. (aerocorner)

Flights near China and Korea proved far more challenging. They were met by pilots that flew far more aggressively, and on occasion, attacked patrols over international waters. While the Skyknight’s were never attacked, they always needed to be wary and tried to limit contact whenever possible. When avoidance was not an option, they were often escorted. Beyond this, the Chinese and North Korean air forces set up fake navigation beacons to try and throw off patrolling aircraft and lure them into their national airspace, where they could then be brought down. These dangers aside, no Skyknights were ever lost during these missions, and they recorded important data on Soviet radar systems.

With VMCJ-3 engaged in its Shark Fin operations in Asia, VMCJ-2 was working closer to home. Their job was to monitor Cuban military expansion flying patrols dubbed ‘Smoke Rings’, beginning in 1960. Unlike the relatively easy job of monitoring early warning radars in East Asia, Soviet technicians in Cuba were keen to keep their work under wraps, and shut down their systems if they thought they were being surveilled. This was soon noticed by the patrolling Marine aviators, who soon learned to fly under radio silence, and operate from less conspicuous airfields, particularly those in the Bahamas and Jamaica. Their work soon paid off, as in the next year, they detected the operation of a P-20 ‘Token’ radar system, used as a ground control radar for MiGs.

The Smoke Rings patrol work built up considerably as the situation in Cuba escalated after the failed invasion in the Bay of Pigs, which would lead to a significant Soviet military build up, culminating in the deployment of ballistic missiles to the island. During this period, the Skyknight’s would prove vital in uncovering, and confirming, the locations of SA-2 surface to air missile sites that would eventually prevent U-2 overflights of Cuba. When the missile crisis arrived, the Marine’s job would be to act as radar jamming support should the crisis turn into a conflict. Thankfully, they were never called upon for that task, though in the years to follow, they still patrolled the island to keep a picture of the situation, and to give new crews practical experience before they were deployed to Vietnam.

Vietnam

While the Marine Skyknight pilots were snooping along the seas of East Asia, and flying rings around Cuba, the US had become embroiled in the brutal civil war which followed the end of French control over Vietnam. Much the same as Korea, this war between two heavily militarized states would see widespread destruction, and a massive technological arms race. Airpower would be a major component to the US strategy, both seeing its traditional use, and a way to offset the considerable numerical disadvantage on the ground. It also proved a way to get around the DMZ between the North and South, which was created to prevent a direct invasion from either side. The Democratic Republic of Vietnam would weather a brutal air campaign with help from their patrons, the Soviet Union and the People’s Republic of China. At first, they had little more than anti-aircraft artillery and various light anti-aircraft armaments, but as was the case in Korea, the Soviet Union would step in and deliver the tools and training needed to build a formidable defense against American air power.

Much like the MiG-15 over Korea, the Soviet S-75 (SA-2) would prove a game changer that shifted the strategies for both sides. (Smithsonian)

The Soviets would provide aircraft, radar systems, and training personnel to build the Vietnamese People’s Air Force an effective GCI system to intercept American bombers. They began modestly, with a small force of MiG 17’s, a subsonic fighter with a gun armament. However, in 1966, the Soviet Union would begin to supply the more advanced, supersonic MiG 19, and the much more modern MiG 21. As impressive as the MiG 21 was, it did not cause the shake up that the deployment of the SA-2 surface to air missile did, which Vietnamese anti-air troops began training on in 1965. The system was robust, easily transportable by truck, and very effective for its day, with the Soviet Union supplying 95 batteries, and over 7000 missiles during the war. The triple layer of defenses, in which lower altitudes were covered by flak, higher altitudes by SAMs, and the MiG’s which were effective in both areas, proved to be a serious danger to American aircraft over northern Vietnam. However, there was a unified weakness that all of these systems shared and could be exploited. They all needed radar support to function.

The Skyknight’s would join a staggering number of aircraft involved with signals reconnaissance and jamming efforts, but among those providing direct support during Operation Rolling Thunder, it was the only major electronic warfare aircraft. Its partner was the EB-66, a faster, sleeker aircraft that boasted a more modern suite of jammers and signals intercept equipment, and was capable of airborne refueling. It was by far the more capable aircraft, but by the start of 1965, they were in short supply. Against them was a fledgling, but quickly growing network of North Vietnamese SAM batteries and ground control stations for MiGs.

The growing EW requirements of the US air strategy would put an intense workload on the Marine EF-10 pilots, while more advanced aircraft prepared to enter service. (Marty Lachow)

VMCJ-1 were deployed to the airfield at Da Nang in April of 1965 under the command of Lt. Col. Otis Corman, with six EF-10B’s and a complement of 93 men. While it might seem odd that so old an aircraft was being brought in for such an important job, both the Navy and Air Force lacked an aircraft that could fully replace it. While the SA-2 missile was known to them in the late 50’s, and had gone on to down U-2 spy planes, budget constraints and a lack of concern over the weapon stifled the timely development of a tactical jamming and signals intelligence planes that could work closely with strike aircraft. While the Navy was to receive the new EA-6A Electric Intruder, technical delays would see it deployed at the end of 1966. As it was, the Skyknight, now known almost universally as the ‘Whale’, was to play an important role in plugging the gap until more advanced aircraft became available.

The Whale’s flew their first missions on April the 19th, flying radar reconnaissance flights throughout Indochina. Their findings allowed them to plot the network of North Vietnamese early warning and fire control radars near their side of the DMZ. As the month came to a close, the air war took a turn when MiGs downed two F-105s. In response, the Whale’s were sent to suppress North Vietnamese ground control radars. Equipped with ALQ-39 jammers configured to counter the enemy’s early warning and flak directing radars, they flew ahead of strike groups, jamming and dropping chaff to confuse MiG ground directors. The EF-10’s were soon in high demand to support Navy and Airforce operations, and it was not long until they were working at a 300 percent higher rate than they were in peacetime. This was later decreased to 200%, but the crews and planes were still operating near their limits.

VMCJ-1 flew both the Skyknight, and the Mach 2 capable F-4R reconnaissance aircraft, representing some of the oldest, and most modern aircraft in US service. (Sam Gill)

DMZ patrols and jamming support continued routinely until the 24th of July, 1965, when an F-4C Phantom was shot down by an SA-2. While, previously, the sites were off limits out of concerns that killing a Soviet advisor might escalate the conflict, strikes against two SAM sites were authorized three days after the Phantom was downed. The mission, Spring High, involved the use of all six EF-10’s acting in support of a strike force of 48 F-105s. The Whales flew as screens for the F-105’s, jamming the radars used by the flak, SAMs, and MiGs. None of the strike aircraft were lost to radar guided assets, but six were lost to low level anti-aircraft fire.

One of the early challenges faced in these missions was the lack of a dedicated escort, which proved concerning, as the defenseless Whales were typically the first in and last out. While none were ever lost to MiG’s, aircrews were often concerned enough to set up informal escort flights with other Navy units. Such was the case with Chuck Houseman, who organized an escort flight with a squadron of Marine aviators who flew F-8 Crusaders from the carrier USS Oriskany. MiG’s aside, the greatest concerns were typically fuel related, as the planes were operating at the limits of their range and carried jammers and chaff dispensers on their wing pylons, where they could otherwise carry additional fuel.

By the end of the summer of ‘65, the SA-2 threat continued to evolve. Batteries sprouted up around the North, and their operators were honing their expertise on this new weapon. Facing the SAMs would require a new set of tactics that blended a mix of electronic deception and fast, aggressive flying. Named Wild Weasel, these strike aircraft were given the dangerous task of venturing into defenses designed to kill them, and tear them down. In this, the Whale was to play an early, vital role. While it had no real offensive capability, it could jam the radars of the anti-aircraft guns and SAMs, and use its signal analyzing capabilities to get a fix on their locations. They would accompany the flights of F-100’s, and later F-105’s, destined to attack the site directly and provide them with vital support. At this early chapter in anti-SAM tactics, most of the strike aircraft lacked the radar warning equipment that gave them an alert when they were being targeted. Until the devices began arriving in mass next year, one of the Whale’s most important jobs was simply to tell them when they were being targeted, and when they needed to go evasive.

In the fall, SA-2 networks and radar guided flak batteries had encompassed much of the North, and the job of the Whale’s grew more complex, and dangerous. The Vietnamese crews too were learning, often setting up several radar stations, while only using one of them to guide their weapons. The Whale’s performed well, but the limits of the aircraft and its equipment became apparent when they suffered their first and only loss to the SAM batteries. In March of 1966, the SAMs would finally catch one of the jamming aircraft, forcing a change in tactics.

With the prohibitions on their use near SA-2 sites, the Whale’s transitioned to supporting Naval operations along the coast. (Jerry Parks)

Following the incident, the EF-10 was no longer permitted within 20 miles (32 km) of a SAM site, and its mission area was effectively pushed out over the coast. This new patrol area would see them mostly supporting Naval operations, as the Navy would not possess their own jamming aircraft, the EA-6A, until the end of the year. The Whale’s new task was to fly in Navy strike aircraft toward the coast to screen their approach with jammers, while also taking note of the active air defenses over Northern Vietnam. They would prove essential, to the point that missions could be called off if no supporting EF-10’s were available.

The Whales would fly a much less conventional mission over Laos and Cambodia, where they aided in the project known as ‘Blind Bat’. In an effort to curtail the supply line known as the Ho Chi Mihn trail, the USAF outfitted several C-130H cargo aircraft with massive night vision devices. Using these, they hoped to spot the faint lights emitted by trucks and bicycle lamps as they made their nocturnal journey south to deliver supplies to the forces of the Viet Cong guerrilla fighters in the south. When the C-130 spotted something, it dropped illumination flares over it, and whatever was exposed would be attacked by the pair of B-57 Canberras which trailed the spotter. The fourth aircraft of the troupe was an EF-10, there to protect the others from radar guided AAA.

They flew off the wing of the C-130, with the two bombers following behind them. While they were never exposed to much of a threat from the ground, the Whale crews who flew these missions considered them the most dangerous during their entire combat tour. It is understandable, considering all four aircraft often flew in blacked out liveries, with a single navigation light atop the C-130 to provide reference between them. Poor weather and moonless nights were also common, as the porters along the trail knew they’d be hardest to spot in such conditions. Little was improved during a successful mission, as the flares and the exploding ammunition along the trail ruined the pilots’ night vision, leaving them to readjust as they turned for home.

End of Watch

By the end of 1966, the Whale’s replacement began to arrive in growing numbers. The EA-6A Electric Intruder was superior in every regard, but it proved unreliable as it went through a rough teething period as it was deployed to the theater. The first arrived at the end of October, ahead of a series of strike operations toward the end of the year. However, the new planes would not be able to do the job alone, and they were joined by the squadron’s venerable EF-10’s. A massive number of strikes were launched starting December 2nd, 1966, under the largest EW umbrella so far, consisting of six Intruders and ten Whales. While the Intruders could handle some of the more dangerous work, the Whales could cover transiting strike aircraft, and monitoring and jamming the growing number of radars for enemy AAA batteries.

A Super Whale departs the airfield at Da Nang. They are distinguished by the lack of any dorsal antennas. (Jerry Parks)

Even into the Autumn of the following year, the EA-6’s were still proving challenging to keep serviceable. It proved frustrating enough that the Corps decided to upgrade its Whale’s to bridge the gap until the Intruder’s readiness rates improved. The ‘Super Whale’ would feature a new broadband radar receiver, an ALR 27 radar warning receiver, and an improved panoramic display for detecting and classifying hostile radar systems. The new suite radically improved the crew’s ability to classify enemy systems and gave instantaneous missile launch warnings. The first of the modified planes was delivered in March, and crews soon flew them on their now familiar missions.

The eight Super Whales of VMCJ-1 continued to fly until September 1969, having been fully replaced by more modern aircraft. By the end of its service it was almost unique in its age, and its pilots often remarked on the fact that few airmen were assigned to something so eccentric. It was an aircraft designed with WWII era technology, and it made its pilots well aware of that fact. There were so few of them that the training materials for the aircraft were sparse, and no formal training program existed, so learning to fly and use the aircraft’s systems was an on-the-job affair. In a sense, each crewman familiarized themselves in their own way. A NATOPS manual was produced, but only near the very end of the plane’s combat tour in Vietnam. Many airmen felt pride in having mastered such an unconventional plane, especially one that flew quite well. Sentiments aside, they all knew it was an extremely obsolete plane kept flying by the kind of resourcefulness the Marine Corps is known for. The newest planes were almost twenty years old and had seen constant use in that time. The stockpile of parts was low, and there was not a single aircraft that was not completely wrung out. As fond of them as some pilots were, they were all happy with their new Intruders, and the Skyknight was finally retired in 1970.

Crew Remarks and Flying Characteristics

From the ground up, the Skyknight was designed to be stable, maneuverable, and to have no quirks in flying that might surprise the pilot. The designers were extremely successful in this regard, with pilots praising solid flying characteristics that some went as far as to call immaculate. Most contemporary jet fighters were known for being a handful, if not outright dangerous to fly, but with its hydraulically boosted controls, spoilerons, and positive longitudinal stability, it was an easy handling aircraft. Even over Vietnam, pilots found it a very forgiving, comfortable aircraft to fly. This being said, no one was ever much impressed by the look of the aircraft, with some pilots remarking that with its broad, flat wings, wide fuselage, and deep set cockpit, that Skyknight was a transport aircraft masquerading as a fighter.

A Skyknight crew prepares to depart. (National Archives)

It was, however, underpowered, having never received engines much more powerful than those on the prototypes. Its top speed was poor, and a fully loaded plane had a downright sluggish climb rate. While it was slow, this did not prevent it from scoring 6 victories against MiGs over Korea, and preventing the rest from chasing B-29’s. However, speed was not the primary issue, but rather reliability. These engines were fairly primitive turbojets developed from the first combat models. Engine failure brought down a number of these aircraft, and exploding turbines would prompt the fitting of armor plating to prevent shrapnel from traveling through the fuselage.

In its intended use as a carrier based night fighter, it was an almost total failure. The plane was simply too large and prone to mishandling by deck crews familiar with much smaller aircraft. It was also almost beyond the capabilities of the hydraulic catapults in use at the time, and accidents would result in serious damage being done to the system. The low cant of the engines scorched the wooden flight decks and ignited any flammable materials, resulting in fire alarms and a shut down of the flight deck. Thus, they could only be kept idling if positioned off the side of the ship. When they were later modified to correct for landing issues, they were controllable on the approach, and generally had good landing characteristics. However, the large flat windscreen was easily obscured by rain, and seaspray in poor weather conditions. The windshield wiper did little to improve visibility on the approach.

While the Skyknight might have been at home on the supercarriers which entered service in the 50’s, they were nothing but trouble on the WWII era carriers of their day. (smithsonian)

When deployed ashore, the issue of the low slung engines remained, and the exhaust was capable of warping, or boring holes, in tarmac. The position of the engines also made them vulnerable to foreign objects and debris on airfields, though this was amended with the use of intake covers which were removed when the aircraft was lined up on the runway. The aircraft was otherwise very capable when operating from airfields.

The Skyknight’s range was also rather short, given the high rate of fuel consumption from its crude turbojet engines. This was mostly resolved through the use of 150, and later 300 gallon (567, 1135 liter) wing mounted fuel tanks. However, in later electronic warfare missions, a jammer or chaff dispenser was often carried on one of the two wing pylons, shrinking the total fuel capacity of the aircraft. Over Vietnam, aircrews would occasionally fly with one engine off while they were transiting to stretch the endurance of the aircraft on longer missions.

The radar suite of the Skyknight was advanced, though its complexity did not lend itself well to ease of use or repair. The AN/APQ-35 featured a gun laying radar, which directed the pilot where to fire, a search radar, which the RO used to find targets, and a tail radar which warned the crew of pursuers. The radar presented information through three scopes.

The AN/APG 26 gun laying radar was the first with lock-on capability, automatically tracking a selected target. This feature was engaged by the RO, who centered the radar on the target and pushed a button. It was useful, but its position ahead of the search radar created a small blindspot. Some crews opted to remove the smaller device entirely to clear the blindspot, and many simply felt it was unnecessary given the high performance of the search radar which could be used to guide the pilot onto target.

The AN/APS 21 was a massive, cutting edge, and very complicated, search radar. It was a truly excellent piece of equipment, but was described by O’Rourke as being designed ‘by engineers that had never flown a plane’. The radar itself was not stabilized, and the plane of the scanning radar shifted with the positions of the aircraft. An RO also had to operate it within certain limitations. If set to a fast sweep at the widest angle, the dish would swing rapidly back and forth, destabilizing the plane and breaking itself. Broken radars were not uncommon given the fragility of vacuum tube electronics, with radar serviceability capping squadron readiness near 60% in Korea.

However, for all its quirks, it was an extremely impressive piece of engineering for its day. The radar was able to detect large contacts at 125 miles (201 km) and had an adjustable search angle that could be set as wide as 170 degrees. For all its trouble, it was worth it.

The massive tandem radar array of the APQ-35. (Jay Miller)

Lastly, the system had an AN/APS-28 tail warning radar which sat at the very end of the aircraft. It was very similar to the older APS 19 radar system found on Corsair night fighters, and thus very familiar to those who retrained for the Skyknight during the Korean War. It employed a small scope on the AN/APQ-35 console and displayed the position of contacts behind the aircraft up to four miles, with a crude approximation of their altitude, with the contact being noted as being as level, above, or below the aircraft. It also had a secondary display consisting of a quadrant of warning lights that would warn the crew of pursuers and their relative distance and position. In service, it was almost useless, as it was set off at lower altitudes and any friendly aircraft nearby, for instance, any B-29’s they might be escorting. The quadrant lights were thus typically removed and the RO would refer back to the dedicated AN/APS-28 radar scope every few minutes.

The AN/APQ-35 suite was later removed when the Skyknights were converted to electronic warfare aircraft, replaced with an EW kit comprised of a panoramic surveillance receiver that displayed the direction of radar and communications systems. It was fed information by a radio direction finder, and a pulse analyzer for identifying radar emissions. The original system used a once quite sophisticated APR-13 receiver, which displayed information on an oscilloscope, and a direct audio output of the radar transmission, to classify and give the direction of ground based radar systems. This allowed the ECMO to identify and locate any number of radar stations, though this took a good deal of work. The Skyknight proved to be a groundbreaking EW platform, but for its crews, this meant dealing with cutting edge yet crude equipment.

Being from the 1950’s, the system was a cumbersome affair that required its operators to manually set operating frequencies and offered no automation of any kind. It could surveil enemy radar systems and provide missile launch warning for friendly aircraft, however, it was nearly impossible to do both at once. Thankfully, in roughly its last year of service, the Marine Corps replaced the analogue EW suite with an APR-33 threat receiver, an ALR-27 missile launch warning system, and a new panoramic display which displayed the entire range of Soviet and Chinese radar frequencies. The new system took a lot of work off the ECMO and automatically warned them of a missile launch, representing a comprehensive upgrade.

Operating the aircraft’s jammers, both on-board and those on the pylons was a relatively straightforward affair. In Vietnam, this virtually always meant using wing mounted ALQ-31 pods that could carry two jammers that were configured to counter different radar systems. While the Skyknight was pulled from the SA-2 jamming mission, it proved very helpful in jamming AAA fire control radars. Crews often remarked that anti-aircraft fire became totally inaccurate once the jammers were in range of the enemy radar system.

Construction

The Skyknight was a solidly built aircraft with a conventional construction. It featured a very wide, monocoque fuselage with folding, mid level, two spar wings. The front of the aircraft contained the search radar or electronic warfare equipment, and the armament, all enclosed in a fiberglass cone. The engines were contained in low slung nacelles within the fuselage, behind which were the airbrakes. At the rear of the aircraft was a conventional stabilizer configuration, with a tail warning radar at the very back of the aircraft. The aircraft had a fully retractable tricycle landing gear arrangement with a deployable tailwheel to prevent tail strikes.

Armament and fuel stores (Standard Aircraft Characteristics)

The wings of the aircraft were of conventional construction, though it saw an early use of hydraulically boosted control surfaces. Combined with a set of spoilerons added to the production series of the aircraft, its roll rate was excellent and maneuverability was retained at high speeds. With the fuselage air brakes allowing for the pilot to prevent overshooting a targeted aircraft, or avoiding overspeed, the plane was remarkably controllable in all aspects of flight. They were designed to fold just beyond the outboard pylons.

The final engine of the aircraft was the Westinghouse J34-WE-36. It produced up to 3,400 lbs (1542 kg) of thrust, leaving the aircraft fairly underpowered. Attempts to re-engineer the aircraft were canceled when the J46 never became available. The J34 was a development of the J30, a WWII era jet engine, and was largely obsolete before entering service due to the rapid strides in turbine development after the Second World War. The engine was an axial compressed turbo jet, with 11 compressor stages, and two turbines. In its early service, it was fairly unreliable and dangerous, as the turbines could break and send their blades through the fuselage, into the second engine. Armored deflectors were thus installed early in its military service. The engine ran on 115/145 octane AVGAS, and not jet fuel, a feature which seriously highlighted its obsolescence in later years.

The console for the APQ-35 contained all of the controls and displays for the three radar systems; it proved compact, but complicated to use. (Pilot’s Handbook)

The Westinghouse AN/APQ-35 radar suite comprised three self contained radar units, being the X-band AN/APS-21 Search radar, AN/APG-26 gun laying radar, and AN/APS-28 tail warning radar. The search radar was by far the largest unit and presented a maximum instrumented range of 200 nautical miles for ground contacts. In airborne use, it could detect targets out to a range of about 120 nautical miles. Its scan area could be adjusted in terms of elevation, and had an adjustable horizontal search angle between 30 and 170 degrees. The search radar sat in tandem with the gun laying radar, with the smaller system ahead of the main unit. The gun laying radar had a maximum range of 4000 yards (3657 m) and was activated by aiming the search radar onto the target and engaging the lock feature. The smaller radar would then automatically track the locked target and adjust the aircraft’s gunsight to give an accurate lead. The tail warning radar had a range of 3 nautical miles and was fixed. The console had three scopes, being a plan position indicator scope, an azimuth scope that gave directional guidance toward the target, and a tail warning scope. Long range target information was displayed on a large plan position indicator scope which was used exclusively by the search radar, while the azimuth scope was shared with the gun laying radar and used to guide the pilot on the final approach to the target.

On the electronic warfare model, the radar suite was replaced by a collection of radio emission monitoring equipment, jammers, and countermeasure dispensers. The original EW suite consisted of an APR-13 panoramic surveillance receiver, replaced in the early sixties with the ALR-8, which included a APA-69A direction finder, and an ALA-3 pulse analyzer. The direction finder and the receiver each had their own console and were used to track and classify actively emitting radar systems. The ALR-8 could monitor most of the Soviet, and Soviet derived, radar systems of its day. This was done with a pair of oscilloscopes, one circular in the case of the panoramic indicator, the other linear in the case of the pulse analyzer, and a direct audio output of the radar emission. These gave the direction and pulse width of the radar system respectively, while the audio output could also be used to identify the pulse width and type of radar system. Each had their own distinctive tone, occasionally allowing for easy classification. A constant pulse rate indicated a fire control type system either directing a SAM or anti-aircraft gun batteries.

EW suite changes, the Super Whale setup is on the right. (EF-10B NATOPS)

These systems were seriously overhauled with the Super Whale upgrade under AFC 199. This included a panoramic ULA-2 indicator console which displayed the directions of all emitting radars, and no longer required the ECMO to manually search frequencies. Defensive upgrades included an APR-33 fire control monitor receiver and an ALR-2 missile launch warning receiver. These upgrades automated much of the ECMO’s workload, and allowed for the aircraft to perform missile warning duties while also investigating radar emissions.

Originally, the aircraft was only equipped with a pair of ALR-2 200 watt jammers, which were acceptable through the 1950’s, but totally inadequate for use over Vietnam. They were typically supplemented by outboard jammer pods and countermeasure dispensers. They often carried an ALQ-31 pod that could fit two jammers, which were typically configured to jam the early warning radars used to provide GCI for MiGs, and fire control radars for anti-aircraft batteries. The other major EW tool was the ALE-2 chaff dispenser, which could be used to create metallic, radar reflecting clouds of aluminum strips. Other avionics included VHF radio communication systems, a UHF radio, a VHF beacon homing receiver, a radio altimeter, and a radio compass. These systems were upgraded throughout the Skyknight’s long career, and new systems, like equipment to use the Tactical Air Navigation System, were added.

The Skyknight’s armament consisted originally of four Hispano Suiza M2 20mm cannons with 200 rounds carried for each weapon. The pilot was provided with a radar directed Mk. 20 Mod. 0 gunsight which could provide automatic targeting for a locked target. On electronic warfare variants of the aircraft, the armament was reduced to two weapons, retained for balance and self defense purposes.

A variety of ordnance could be carried on the outer pylons, being unguided bombs up to a weight of 2000 lbs (907 kg) per pylon. The 11.75” ‘Tiny Tim” rocket could also be mounted, though it is unlikely they were ever used, as only a handful of ground attack missions were carried out with this aircraft near the end of the Korean war, and only with unguided bombs. The pylons were otherwise used only for carrying 150, or 300 gallon fuel tanks (567, 1135 liters), in addition to the electronic warfare equipment described above.

The Skyknight featured more creature comforts than most other navy fighters by the time of its design. It was air-conditioned, its floors were carpeted, and an electric cigarette lighter was installed in the instrument panel, with ashtrays at the crew’s elbows. It was perhaps the only fighter aircraft to be equipped with a built-in cigarette lighter. However, it was not retained on the EF-10 and the engineers at Douglas removed it when they were updating the instrument panels. Both crewmembers were provided with urinals in the form of relief tubes for use on long flights.

F3D escape diagram. (Pilot’s Handbook)

The escape system consisted of a chute positioned between the crewmen, and at its end was a panel which would be ejected by means of explosive bolts. The crew would then use a bar over the opening, at the rear of the cockpit, to hurdle themselves down the chute and clear the plane. It was effective, though it meant that one could not safely bail out of the aircraft below 2000 ft. Crewmen who ditched the aircraft were to escape via the roof panel, which also doubled as the means to enter and exit the plane.

Conclusion

A preserved Skyknight, ironically stored aboard the USS Intrepid. (Tony Inkster)

In spite of failing in its original goal almost completely, the Skyknight’s career in the Marine Corps saw it become the unsung hero of two wars and earn the respect of its crews. It seems almost impossible that an ungainly nightfighter rejected for its original use could have ever brought down cutting edge MiG’s, made the Air Force’s B-29’s untouchable, or claim the night skies over North Korea for its own. Yet in the end, the Marine’s made due, and ‘Willy the Whale’ became one of the most successful fighters in the theater. Beyond this shocking combat debut, it almost effortlessly transitioned into an entirely different role, surveilling radar systems and providing electronic support for US forces in the technological cat-and-mouse race over Vietnam. Developed in an age when planes had their operational life spans measured in months, the Marine Corps flew the Skyknight for almost twenty years, a testament to its ruggedness and versatility.

F3D-2

Specification

Engine Westinghouse J36-WE-36
Engine Maximum thrust 3,400 lbs (1542 kg)
Fighter weight internal stores only 24,614 lbs (11,164 kg)
Fighter with 2 x 150 gal tanks 26,731 lbs (12129 kg)
empty weight 14,898 lbs (6757 kg)
Combat Range [with external fuel] 1,195 nmi
Combat Range [internal stores] 995 nmi
Maximum Speed 426 kts @ 15,000 ft (4572 m)
Cruising Speed 395 kts
Combat Ceiling 35,000 ft (10,668 m)
Armament 4x 20 mm Hispano Suiza M2 cannon
Crew 1x Pilot

1x Radar Operator

Length 45′ 5″ (13.84 m)
Height 16′ 1″ (4.9 m)
Wingspan 50′ (15.24 m)
Wing Area 400 sq.ft (37.16 m2)

Variants

F3D-1 (F-10A): First production version, J34-WE-34 engines. 28 built.

F3D-2 (F-10B): Improved, final production model. J34-WE-36 engines, lock on capability, General Electric G-3 autopilot, wing spoilers. 237 Built, final aircraft built in March of 1953.

F3D-1M: Sparrow missile testbed.

F3D-2M (MF-10B): Four missile hardpoints, no cannons. Brief service life. 16 converted from F3D-2s.

F3D-2Q (EF-10B): Electronic Warfare Aircraft. 35 Converted from F3D-2.

F3D-2T: Night fighter trainer. 5 converted.

F3D-3: Proposal, swept wing night fighter with J46-WE-3 engines.

Illustrations

 

VMF(N)-513, Korean War. During their combat tour ,The Flying Nightmares developed a superstition around aircraft numbered 13. The crew of this aircraft improvised an alternate number.
VF-14, USS Intrepid, 1954. The Top Hatters were among the last squadrons to fly the Skyknight as a night fighter. They quickly transitioned to more modern fighters.
VMCJ-1, Da Nang, Vietnam War. in 1967, all of the in-theater EF-10B’s were upgraded to ‘Super Whales’. They continued to serve for two more years before being phased out by more modern aircraft.

 

Credits

  • Article written by Henry H.
  • Edited by  Stan L.
  • Ported by Henry H.
  • Illustrated by Hansclaw

 

Sources:

Primary:

“Eyes In the Night”. Naval Aviation News. V33-34 1952-1953.

Pilot’s Handbook Navy Model F3D-2 Aircraft. Secretary of the Air Force and the Chief Bureau of Aeronautics. 15, July 1952.

NATOPS Flight Manual Navy Model EF-10B Aircraft. Chief of Naval Operations. 1 April 1969.

Night Fighters Over Korea. G.G. O’Rourke with E.T. Woolridge. Naval Institute Press.

Standard Aircraft Characteristics F3D-2 “Skyknight”. 15 February 1952.

Secondary Sources

F-3D/EF-10 Skyknight Units of the Korean and Vietnam Wars. Joe Copalman. Osprey Publishing. 2022.

F-105 Wild Weasel vs SA-2 “Guideline” SAM. Peter Davies. Osprey. 2011.

All Hands. No. 648-658. 1971.

Naval Fighters Number Four Douglas F3D Skyknight. S. Ginter.

Korean Air War Sabres, MiGs and Meteors 1950-53. Michael Napier. Osprey. 2021.

Naval Aviation News, Obituary Heidemann, Jan-Feb. 1992.

Skyknight. R.E. Williams. Naval Aviation News. 1983.

Into the Jet Age: Conflict and Change in Naval Aviation , 1945-1975. E.T. Wooldridge. Naval Institute Press. 1995.

A History of Marine Fighter Attack Squadron 531. Colonel Charles J. Quilter II and Captain John C. Chapin. History and Museums Division Headquarters, US Marine Corps. 2001.

US Marines in Vietnam High Mobility and Standdown 1969. Charles R. Smith. 1988.

Sparks over Vietnam The EB-66 and the Early Struggle of Tactical Electronic Warfare. Captain Gilles Van Nederveen. College of Aerospace Doctrine, Research and education. 2000.

Aircraft Carriers a History of Carrier Aviation and its Influence on World Events Volume II 1946-2005. Norman Polmar. Potomac Books. 1969.

Focke-Wulf Ta 152H

Nazi flag Nazi Germany (1945)

Fighter: Approximately 60 built

A Ta 152H undergoing compass calibration. (flugrevue)

Introduction:

Throughout the Second World War, the job of the interceptor would become ever more challenging. Their targets, mostly bombers and photo reconnaissance aircraft, would fly ever higher and faster thanks to new advancements in turbo and supercharging. With Germany under a state of permanent siege and surveillance by aircraft like the Boeing B-17 and De Havilland Mosquito, it was clear the Luftwaffe needed a specialized interceptor to effectively reach these high flying threats and the multitude of new fighters that were appearing in growing numbers. After several failed attempts to develop the Fw 190 into such an interceptor, Kurt Tank designed the Ta 152H. The short lived design incorporated all of the available developments in high altitude flight available to German aviation in an attempt to create the ultimate high altitude fighter.

High altitude threats and Interceptors

In the summer of 1941, the Mosquito was making its first reconnaissance sorties and becoming one of the gravest threats to German aerial defenses. Operating above 7km and capable of reaching speeds upwards of 560 km/h, the aircraft was almost untouchable after it had reached its destination. Once they had taken their photos, they turned for home and entered a shallow dive that allowed them to accelerate to speeds beyond those of pursuing fighters who were not already chasing them from a higher altitude. With such a small interception window, they were a chief concern to the Luftwaffe. Doubly so were the bomber variants of the aircraft, which raided targets all over North Western Europe.

The following year saw the entrance of the United States into the Second World War, their air force possessing some of the most capable high altitude aircraft at the time. Investments in engine turbocharging allowed them to field a number of bombers and fighters with exceptional high altitude performance. B-17’s were conducting regular operations above 7 km. At first, they undertook operations at significantly lower altitudes, never straying too far from their air bases in southern England, but it was becoming clear that they would soon pose a threat that the Luftwaffe was ill equipped to combat.

The De Havilland Mosquito was quickly recognized as a serious threat not long after its introduction. Photorecon versions, like this later Mk XVI here, could surveil Germany with little fear of interception. (wikimedia)

The only two fighters of consequence employed by the Luftwaffe, the Bf 109 and Fw 190, were effective low to medium altitude fighters. However, through 1942, both were operating with engine power restrictions, and supercharger related performance bottlenecks. While inferior alloys and lubricants were causing a variety of issues, that was less of a concern than the engines themselves not being designed for use at high altitudes. The Bf 109G’s DB 605A, with its variable single stage blower, provided a full throttle height of roughly 6.5 km, depending on the variant. The Fw 190’s BMW 801, with its significantly simpler, single stage, double speed supercharger, was even worse off. Its critical altitude was only roughly 6 km, leaving it, and the 109, distinctly lacking in power at the over 7.5km B-17’s often flew at. Above these altitudes, neither engine could maintain the manifold pressure needed for combat power, putting them at a distinct disadvantage in trying to catch the Mosquito, or fighting American high altitude fighters which were soon making forays into German airspace. As the USAAF began its strategic bombing campaign against Germany proper, there were deep concerns within the Luftwaffe about the battle they were soon to fight, and for which they were clearly technically unprepared for. Even more concerning was the fear that the RAF would soon be operating the Vickers Wellington V bomber, which was reportedly capable of operating at an almost untouchable altitude of 12 km. They never entered service, but were the impetus for the creation of a specialized high altitude fighter with the Höhenjäger program.

With these anxieties building, the RLM convened a conference on the development of high altitude fighters on May 20, 1942 at Messerschmitt’s plant in Augsburg. In addition to the high altitude British bomber, further concerns were spelled out over the recent study of the new Merlin 61 engine, which, with its two stage, two speed supercharger, promised to make the Spitfire and Mosquito even more challenging opponents at high altitude. Of particularly grave concern was that the German aviation industry could not simply follow the same development path as the Allies. The poor qualities of their available alloys and the inadequate supplies of high octane fuels meant that even, if they had a factory furnished with all the tools to manufacture an engine like the Merlin 61, they simply could not build or operate it with the materials at hand.

As such, they had to pursue less conventional means of improving performance. Messerchmitt proposed a redesign of a former naval fighter proposal for high altitude use. The Me 155 carrier based fighter design, with its very long wingspan, was proposed to be converted for high altitude use, the work being done mostly at the S.N.C.A.N plant in Paris. The design would later be taken up and heavily altered by Blohm & Voss, who went on to design the Bv 155, with turbochargers and GM-1 nitrous boosting. Neither design came to fruition. A secondary design, the Bf 109H, would involve stretching the wingspan of a Bf 109F, and later G, and installing the high altitude GM-1 engine boost system. Likewise, this design was not pursued. In the end, Messerschmitt would go on to design a mass production, high altitude variant of their standard Bf 109G with a pressurized cockpit and nitrous boosting. While it would prove fairly adequate for the time, it was held back by the need for GM-1, which was difficult to transport in large quantities without a pipeline.

Focke-Wulf would face an even greater challenge with their program. While their Fw 190 was proving to be among the best medium altitude fighters of the war, its short wingspan and outdated supercharger meant it would take a considerable effort to make a high altitude fighter out of it.

The Höhenflieger Fw 190

Focke-Wulf first pursued turbocharging to get their fighter to reach the adequate level of performance for the Höhenjäger project. Almost immediately, they ran into the issue that it was almost impossible to fit a suitable turbocharger into a Fw 190A, though an externally mounted, and almost completely unwieldy unit was suggested. The first serious effort came with the proposal for the Fw 190B fighter, or Höhenjäger 1, in August of 1942. The design would take the then in production Fw 190A-3, increase its wingspan from 10.5 to 12.4 meters (increasing its area from 18.3 to 20.3 m^2), and install a pressurized canopy. The engine was initially unmodified and nitrous boosting was not pursued, in the hope a suitable turbocharger would be developed. The prototype, Fw 190V-12, began testing, but was abandoned in favor of using older, pre-production Fw 190A-0 prototypes before moving on to pre-production. The Fw 190B-0 received the new BMW 801 D-2 and several other modifications going into the new A-5 fighter. It began testing in December of 1942, and despite some faults with the pressurized canopy, which were later corrected, the aircraft had considerably better high altitude handling than the original A model. All four of the A-0’s were converted, but the program showed little promise. Despite the effort, the improvements were not enough and the aircraft was still too slow at high altitude. It was clear that the aircraft needed a heavily modified, or entirely different engine, in order to attain the level of performance needed.

Perhaps the most promising development for the next generation of the Fw 190, the C series, hoped to install a much more powerful DB 603 engine. Harsh teething issues and limited supplies for the engine doomed the project. (grafiq)

In parallel with the B-project, the decision was made to re-engine the aircraft with either the Junkers Jumo 213, or Daimler Benz’s DB 603. Both promised better high altitude performance over the BMW 801 along with a considerable overall increase in engine output. The DB 603 project would proceed with the designation Fw 190C, and the Jumo 213, Fw 190D. The first Fw 190C prototype, V13, had a DB 603 installed, with an annular radiator at the nose of the aircraft and its supercharger intake mounted between its two oil coolers, these modifications presenting a longer, but more streamlined profile. Little drag was added to the airframe with the modifications initially, but they would be forced to mount the supercharger scoop externally. The aircraft first flew in March of 1942, and overheating, along with general teething issues would be noted. Two more prototypes were converted, V15 and 16, receiving the longer wing from the B-project and GM-1 equipment. Turbocharging was also proposed, but not pursued until much later on. The program continued through May at a decent pace and they were achieving high speeds, one aircraft reaching 696 km/h at 6,950 m, but overheating and engine failure remained serious issues. Similar problems were likewise being experienced with the Jumo 213. The results, however, prompted Focke-Wulf to expand the program with six more prototypes, V13,15,16, 19, 20, 21, 25, 26, and 27 carrying the DB 603, and V22 and 23 using the Jumo 213. Despite the focus on the DB 603, the company was prepared to switch to the Jumo 213, which they could obtain a much larger supply of.

The large, drag inducing turbocharger scoop earned this aircraft the moniker ‘kangaroo’. Aerodynamically unsound, it proved unsatisfactory for service. (wwiiforum)

The final design for the Fw 190C featured the DB 603A with its supercharger intake mounted on the port engine cowling, with various provisions for an armament of MG 131 machineguns, MG 151/20, and MK 108 autocannons. Its highest tested speed was an impressive 722 km/h at 9 km, without armament or armor plates. Production was strongly considered, and then canceled. The DB 603, in its fighter configuration, was still proving troublesome, and V13 was written off after an engine failure forced the pilot to crash land. The engine itself had a comparatively small production run compared to the Jumo 213, and was being shared with a number of twin engine bombers and night fighters. As the older, and massive Jumo 211 production lines were transitioning to the more powerful Jumo 213, it was by far the better choice for a new mass production fighter.

The Fw 190D or ‘Dora’ project continued, though its development path did not lead to a mass produced, high altitude fighter. Rather, it became a project to facilitate getting the Jumo 213 into a fighter as fast as possible, as it was one of the few German engines capable of competing with Western Allied models in most areas. The only mass produced variant, the D-9, is often mislabeled as a high altitude fighter, though its engine was designed for low to medium altitude use. A small number of high altitude models, with the appropriate engines, were produced, but were nothing compared to the D-9’s production run of well over a thousand aircraft by the end of the war.

Shifting programs aside, Focke-Wulf would continue with the new Höhenjäger II project, now seeking to build a truly superb high altitude fighter by taking several of the Fw 190C prototypes and equipping them with Hirth TK 11 turbo-superchargers. With the Fw 190B improvements, the 2000 hp DB 603 S, and a pressurized cockpit, it was hoped that a number of exceptional high altitude fighters could be produced, even if they could never reach the production figures of the Dora. They attempted to solve the earlier issue with the unmanageable size of the turbosupercharger by installing it partially outside of the fuselage, with an air scoop at its front. V18 received the necessary modifications and flew in December of 1942, with serious cooling problems being noted. Further modifications were made after the first several flights, most notable being that a larger oil cooler was mounted, the tail was enlarged to improve high altitude control, and the next prototype, V30, was re-equipped with a four bladed Schwarz propellor. Their extreme high altitude performance was superior to the C, with the aircraft reaching a speed of 670 km/h at 11 km, though they were proving far more temperamental. Turbine and engine issues continued to cut test flights short, though more prototypes were constructed through early 1943, V29 to V33. However, turbine issues persisted, and the entire scoop set up was found to be aerodynamically poor, and the design was proving very disappointing in comparison to the fully recessed models in service with the USAAF. Its performance too was deemed inadequate, and the project was canceled.

Falling behind

Apart from expedient designs, like the GM-1 boosted Bf 109’s, German efforts to produce a high altitude fighter had largely stagnated during 1943, and by the beginning of 1944, they were at a distinct disadvantage. For the past two years, most of the aero engine industry was working hard to modify their existing models to run at their full power using the inferior materials and fuel that were available to them. Among the clearest problems this caused was with the Messerschmitt Bf 109 G, or ‘Gustav’ model, which was only finally cleared to run at its full combat power in the summer of 1943, almost two years after its introduction. Under such conditions, developing new engines was a mostly hopeless effort, and to make matters worse, Allied developments in this field were unfolding brilliantly. While Focke-Wulf and Messerschmitt had failed to deliver on their high altitude fighters, the RAF began to fully transition to the use of the two-stage Merlin in their Spitfires, while the even more powerful Griffin was in development. By the end of 1943, USAAF finally introduced the P-51B, using a licensed Packard Merlin engine, and the P-47 had seen significant performance improvements which gave it unparalleled performance above 9 km. The P-51 proved perhaps the most concerning, as it not only had the benefit of a significantly more advanced engine, but it had been designed with aerodynamic concepts that were not available to aircraft designers before the war. It was an altogether modern aircraft, whereas the German air force would remain dependent on modified versions of planes which had been flying before the war had begun. The Bf 109G had fallen behind its Western contemporaries in most areas of performance, while the Fw 190 still clung to a competitive edge in low to medium altitude engagements. At high altitudes, especially above 7.5 km, there were only a comparative handful of GM-1 boosted Bf 109G’s that could really challenge the Allies, and even then, not on equal terms.

Germany did not possess the materials needed for robust and reliable exhaust valves, bearings, or more efficient, high pressure, high temperature radiators like those on Western Allied planes. However, there were areas of hopeful improvement. Foremost was that, by the autumn of 1943, German engine manufacturers had developed nickel coatings for engine pistons to overcome corrosion problems, and had modified the DB 605’s oil scavenge system to allow it to run at its originally planned combat power. While they would not be able to produce engines as reliable as those in the service of the RAF and USAAF, it was clear that the performance disparity could be reduced. Just as crucially, improvements were being made in regards to radiator design, particularly the annular units which were being tested on the high altitude Focke-Wulf projects. The new AJA 180 on the Fw 190 series was both approaching the pressure and temperature tolerance of Allied models, and was very compact, allowing the Fw 190 to retain its aerodynamic sleekness even when it switched engines.

The Fw 190D project transitioned away from high altitude fighters when the demand for better general purpose fighters grew. Rushed into production, it had more than its fair share of blemishes but, nonetheless, was an effective successor to the earlier ‘Anton’. (worldwarphotos)

While Messerschmitt had already succeeded in producing an acceptable high altitude fighter in the GM-1 boosted Bf 109G, Focke-Wulf’s projects took a different turn. The high altitude Fw 190D project shifted focus to produce a medium altitude fighter, the Fw 190D-9, and another project would seek to build a successor to the Fw 190, the new plane being named Ta 153. The designation changed to reflect Kurt Tank’s role as the head designer at Focke-Wulf. With this new design, hopes for significant high altitude improvements were again stoked, but as had become clear by their earlier failures, such improvements could not come from any unfamiliar solutions or technically complex methods, like turbocharging.

The Successor

The Ta 153 was so designated as it was not a variant, but a successor to the original aircraft. It featured a new fuselage and wings and the occasionally troublesome electrically driven landing gear actuators were changed for hydraulically driven ones. Being almost entirely divorced from the Fw 190’s supply chain, it was thus denied for production in March of 1943, given the amount of labor and time it would take to set up tooling. A compromise model between the design and the Fw 190D was selected, designated the Ta 152.

The Ta 152C program attempted to replace the Fw 190 A&D and correct the faults of the Dora. In the end, it proved too similar to justify shifting production before the end of the war. (ta-152.de)

There were several types planned, namely Ta 152 A,B,C and H. These were standard fighters, heavy fighters for use against bombers, fighter bombers, and a high altitude interceptor. The A and B were designed to use the Jumo 213A & E, respectively, the C the DB 603, and the H, the Jumo 213E. To avoid impacting the production of the Fw 190D, the high altitude model was the first to be developed. These planes featured a hydraulic landing gear system as opposed to the electric actuators on the Fw 190, an improved vertical stabilizer from the Fw 190C program, larger wings, and a half meter fuselage extension in the rear fuselage, with the ensuing redistribution of weight helping to correct for an issue with the aircraft’s center of gravity.

While it may seem odd that they were essentially pursuing two fighter designs to succeed the Fw 190A, the Luftwaffe was desperately looking for higher performance fighters. Hopes were placed on the new Jumo 213 in the Fw 190D, and the new DB 605D in the Bf 109K, to keep pace with the Allies. The Dora was an expedient solution which could use the same supply chain as the original fighter, and the Ta 152 would be a more thoroughly improved model which would be transitioned to once the Dora’s supply chain was well established. In any case, only the high altitude Ta 152 variant was pursued with any substantial amount of resources, given it would be assigned a mission the Bf 109K and Fw 190D models were not suitable for. Jets were, of course, also quite promising, but they were still an immature technology, and it was clear that the leap from pistons to turbines could not be made in 1944.

The new fighter would be designed with both high altitude and low altitude performance in mind. To meet this challenging requirement, both the GM-1 high altitude, and MW 50 low altitude engine boost systems were to be installed aboard the aircraft. Kurt Tank selected several of the old Fw 190C prototypes to be converted for the new program, these being V18, 29, 30, 32, and 33. V33 was the first to undergo modification and was redesignated V33/U1, now featuring a three bladed VS 9 propeller, a forward fuselage lengthening of .5 meters, a rear fuselage lengthening of 0.772 m, a new high aspect wing with an area of 23.5m^2, a hydraulically actuated undercarriage, and two 20 mm MG 151/20’s mounted in the wing roots.

It first flew on July 13, 1944, and was lost after it crashed during its 36 minute test flight at Vechta. The second prototype, V30/U1, flew on August 6, and like the first, was again lost, though this time resulting in the death of its pilot, Alfted Thomas. More success was had with the third prototype, V29/U1, which flew on September 29, 1944, and the fourth, V18/U2, which flew shortly after. With pre-production beginning in November, this left them about a month to perform flight tests on their surviving prototypes.  Serious trouble with the program was encountered as late as November, when test pilot Hans Sander had to crash land his aircraft after his engine seized due to fuel starvation. It was found a hydraulic valve had been installed in the fuel line, an accident most likely a result of the aircraft’s rushed development.

The losses and damages experienced at this point in testing were threatening to seriously interrupt the pace of the project, but in the end, they rushed through development with some of the stability issues unresolved. This effectively led to the aircraft entering production with only slight adjustments from the prototypes. However, the plane was achieving good high altitude performance, both in terms of speed and ceiling. Test pilot Friedrich Schnier would fly V29/U1 to an incredible height of 13.6 km on January 20th, 1945. Beyond this, the fourth and final converted aircraft was V32/U1, which was fitted with a four bladed Schwarz propeller and the new MG 213 revolver cannon. It first flew in January of 1945, though none of the equipment would be worked into any production aircraft.

The eccentric profile of the aircraft, with its high aspect ratio wings. (destination’s journey)

The H was unique among the Ta 152 series, with its long, high aspect wings designed for high altitude use, a pressurized cockpit, and the installation of both the GM-1 high altitude, and MW 50 low altitude boost systems. While together, they promised incredible performance at any height, GM-1 was never carried aboard any of the operational fighters due to its container’s adverse effects on stability. Eager to have this aircraft as soon as possible, Focke-Wulf sprinted through its development, and the Ta 152H entered pre-production in November of 1944. The extremely rapid pace of development was emblematic of the very desperate situation the German air force was in at the time. This resulted in the delivery of an aircraft that was effectively unfinished.

The Ta 152H-0 entered service without several of the key features that the plane was set to carry, lacking the outer wing fuel tanks, and the engine boost systems. As such, it was considerably lighter, and better handling than the planned production model, but without the boost systems, it was much slower.  For the time being it judged necessary, as there were serious weight distribution issues with wing fuel tanks and boost systems aboard. While it was designed with wing tanks, GM-1, and MW 50, the production model of the aircraft would not be permitted to fly with all three. In the end only the MW 50 and the wing tanks were permitted to be used together, but the GM-1 system would prove more troublesome. A stop gap solution late in the war would allow for the use of GM-1, but only GM-1. By the time the war ended, there was still no solution on how all three pieces of equipment would be added to the plane without jeopardizing its flying characteristics.

It was in this rough state when it was delivered to the Luftwaffe for testing in December. Due to supply chain issues, production was slow and the aircraft were finally delivered to the Luftwaffe until January 27, 1945.

Operational History

Given their very late introduction during the war, the Ta 152H saw very little action and its combat record is extremely limited. The aircraft was only supplied to the Stab, the squadron staff group, and Gruppe III of JG 301, a dual night and day fighter squadron which transitioned to them from Fw 190A-8’s on January 27. The squadron had a good pool of experienced pilots already familiar with Focke-Wulf aircraft, though their mechanics would have a far more difficult task, as the Ta 152H-0 had been pushed into service without maintenance manuals. At the airfield at Alteno, they received 11 aircraft, with 16 others having been destroyed or damaged on the ground before they could reach the unit. Familiarization and training proceeded until the end of February and was not without incident. One aircraft (150037) was lost in a training incident, a second damaged but repaired, and serviceability fell from 75% to 30% after an incident with water contaminating fuel supplies. The squadron would go on to receive several more aircraft before rebasing to Sachau when Alteno was overrun. They would attempt to engage Allied bombers on March 2, but the 12 Ta 152H’s would fail to reach them, as they were attacked by the Bf 109s of another squadron which mistook their unfamiliar planes for the enemy. No aircraft were lost in the engagement. A second high altitude interception against a DeHavilland Mosquito was also attempted, though engine trouble forced the pilot to return to base before contact was made.

One of the only photographs of Ta 152H’s in operation with JG 301. (destination’s journey)

The unit rebased again to Stendal near Erfurt, where they joined JG 301’s Gruppe II, during which one aircraft was lost, and the pilot, Jonny Wiegeshoff, was killed on the landing approach. This was believed to be the result of the propeller reduction gear failing and becoming stuck in an almost feathered position. By March 14th, the understrength unit was supplied with several Fw 190A-9s. Outnumbered and with little security, the Ta 152H’s often flew top cover for the rest of the unit during what few operations were undertaken. On April 10, Erfurt was contested, and during the fighting, the eight serviceable Ta 152’s engaged a flight of fifteen P-47’s near Brunswick, resulting in one victory claim.

Gruppe III’s last actions were conducted from Neustadt-Glewe. On April 15th, the unit suffered its first combat loss. During operations that day, four Ta 152s sortied to attack a pair of RAF Hawker Tempests engaging in a low level sweep. According to Obfw. Willi Reschke, the Ta 152H in the number two position, flown by Obfw. Sepp Sattler, suddenly lost control and crashed before contact was made, seemingly suffering a fatal malfunction, while other accounts claim he was brought down by one of the RAF Tempests. The remaining two Ta 152’s engaged the Tempests of No. 486 Squadron. In the ensuing battle, Obfw. Willi Reschke entered an intense, low level dogfight with one of the Tempests. Near the beginning of the engagement, he fired on and struck the tail of a Hawker Tempest flown by Lt. Mitchell, his gun’s electrical circuit seemingly failing shortly after. However, when Mitchel attempted to turn away from his opponent, he lost control of his damaged aircraft and crashed. Reschke swore by the low speed maneuverability of the Ta 152, which he felt was critical in this engagement, and his survival through the last days of the war. The Ta 152H flown by the Schwarm leader, Oberstleuteneant Fritz Auffhammer, suffered an engine failure, though the pilot successfully restored power and returned to base with his supercharger broken. Sattler and Mitchel were both buried at a cemetery in Neustadt-Glewe.

The last actions of the squadron were in the last stages of the Battle for Berlin, and on April 24th, the Ta 152s and Fw 190As of the IInd and IIIrd Gruppe attacked Soviet positions and engaged Yak 9’s. The final mission was flown over Berlin in poor conditions, and during an engagement with a flight of four Yak 9’s, Hauptman Hermann Stahl was killed during the engagement, with the four Yak-9’s being claimed by the unit. After the surrender, the unit rebased to Leck in Schleswig-Holstein, where they were disbanded and one of the serviceable Ta 152H’s was transferred to England by the RAF so that it could be evaluated. A second Ta 152H was also claimed by the USAAF for evaluation purposes, the plane being another H-0 which likely belonged to a testing unit at Rechlin.

One of the only serviceable planes was taken to the UK for testing. The other was taken in hand by the US. (Alessandro Orseniga)

In all, the Ta 152H was never actually used for any high altitude combat operations and its service was restricted to a single under strength unit. With at most ten victories and four operational losses, it is difficult to give any appraisal for its performance from its brief career with JG 301. Obfw. Josel Keil, was the only pilot to qualify as an ace on the Ta 152H, and together with Willi Reschke, who had two credits in the Ta 152H, and 24 in other aircraft, held nearly all of the aircraft’s combat credits between them.

Handling and Flying Characteristics

While the Ta 152H’s combat record leaves a lot of questions left unanswered, most pilots who had the chance to get behind the controls of the aircraft can at least agree that the aircraft flew very well. Among its most famous advocates was Royal Navy Test pilot Eric Brown. He would praise its excellent climb performance, maneuverability at high altitude, stability, and good landing characteristics. His only negative remarks were that its roll rate was reduced over the older Fw 190A, that its stick forces were notably heavier, and that its wheel brakes were still awful and prone to fade after a few moments of use. He otherwise considered it an excellent aircraft and the best high altitude piston engined fighter he had flown, comparing it favorably to a Spitfire Mk IXX. It must be noted that he misidentifies the aircraft as an H-1 in his book, and not the substantially lighter H-0, which is visually identical.

Captain Brown’s remarks are matched by those of the pilots who assessed the aircraft in the Stab and III/JG 301. The Ta 152H-0 had the best evaluation received by a front line operator of a Focke-Wulf aircraft. The aircraft possessed most of the best qualities of the earlier Fw 1,0D-9 without having its poor accelerated stall characteristics. While still described as uncomfortable like the Fw 190D it was so similar to, it was much improved and less prone to the aggressive snap rolling. So, while the aircraft was less maneuverable, generally speaking, most pilots were more comfortable pulling harder turns. In tests at the unit, some new pilots in Ta 152H’s were able to turn with seasoned pilots in Fw 190A’s. Take off runs were short, and the landing approach could be conducted at low speeds. Generally speaking, it was a fairly forgiving aircraft. The only negative notes on the aircraft were from the findings of the Rechlin Test Center, which found the aircraft became seriously unstable in dives exceeding 600 km/h and that level flight required excessive trimming of the horizontal stabilizer.

The enlarged tail and redesigned wings helped give these aircraft better handling characteristics than the Fw 190D. (Grafiq)

The stick forces were notably fairly high, but they were harmonized well, and the push rod control system ensured inputs were very responsive. Stability about the vertical axis was poor, and there was a tendency to skid. This tendency grew worse at higher altitudes and motivated them to install a level flight autopilot. The aircraft possessed good visibility to the back, sides, and rear, with the view over the nose being mediocre to poor. The controls were placed conveniently, with the instrument panel layout being clean and easy to read.

Most of its good qualities were not found in the fully equipped H-1 production model of the aircraft. Numerous problems were encountered when the full set of engine boosting equipment and fuel tanks were installed and filled. The added weight of the boost systems and wing tanks was substantial, and asymmetric. The GM-1 system and the wing tanks were particularly problematic, and the aircraft was unstable if the GM-1 container and fuel tanks were filled. Stability with the GM-1 system was only possible with a ballast kit, empty wing tanks, the removal of the MW 50 system, and a set fuel limit for the rear fuselage fuel tank. These issues were not resolved by the time the war ended, and there was no way the aircraft could use any combination of these systems without seriously jeopardizing its flying characteristics. MW 50 was usable aboard only the H-1 production model, but it may not have been available to JG 301 in the field. The squadron was still mostly composed of BMW 801 equipped Fw 190A’s which did not use the system.

Mechanics generally found the aircraft easier to maintain than the Fw 190, however there were some issues. The new hydraulic system for the landing gear was experiencing teething and quality control issues. The position of the landing gear wheel well was also found to be at issue, as when launching from damp conditions, the propeller cast mud and water into the well, which made its way inside the wing. This caused issues with the hydraulic systems and the autocannons fitted in the wing root.

Comparisons with contemporary fighters

The Ta 152H represented a leap in Germany high altitude fighter design, though not necessarily one that took them beyond the competition. (flugrevue)
Aircraft (manifold pressure) Speed at Sea Level (km/h) Speed 3050 m (10,000 ft) (km/h) Speed 6096 m (20,000 ft) (km/h) Speed 9144 m (30,000 ft) (km/h) Speed 9.5 km (31,168 ft) (km/h)
Ta 152H-1 (1.92 ata) 580 640 690 725 732
Fw 190D-9 (1.82 ata) 611 645 689 653 645
P-51B-15 (75″ Hg) 616 675 709 688 685
P-47N-5-RE (72″ Hg) 587 643 708 740 759
P-47M (72” Hg) 587 646 701 753 762
P-38L (60” Hg) 550 608 646 663 659
Spitfire Mk 21 (+21 lbs) 592 658 700 704 703
Me 262 A-1a 800 x 870 845 x

*The Ta 152H-1 could reach a maximum speed of 760 km/h at 12.5 km using the GM-1 boost system. While it was never cleared for operational use, on paper, it made the Ta 152H the fastest fighter at that altitude. The Fw 190D-9 represents a late model, having received an MW 50 boost system, as was available near the end of 1944.

The Ta 152 entered service on a battlefield where the Western Allies already had high altitude supremacy, and had a number of improved designs that had yet to make their debuts by the time the war in Europe was ending. By January of 1945, the German air force was no longer dealing just with long range escort fighters over its own soil, but virtually every fighter the Allies could throw at it, such as P-47’s, Spitfires of several marks, La-7’s, and Tempests, just to name a few.

Fw 190D-9 (Graphiq)

Against its contemporary Fw 190D-9 counterpart, it is clear that the Ta 152H did not represent a comprehensive upgrade. The Dora shared much of the same fuselage, though it retained the wings and tail sections of the older Anton series fighter, and it carried the Jumo 213A engine designed for use at lower altitudes. In regards to linear speed and acceleration below 6 km, the Dora roughly matched or exceeded the Ta 152H. This, however, was not the case at higher altitudes, where the high altitude specializations of the fighter showed their worth. The Ta 152H was known to be more maneuverable in flat turns and much more forgiving in most aggressive maneuvers, a result of its high aspect ratio wings which lacked the less than ideal tendency for snap rolling without much warning that the older Fw 190’s were known for. In a dive, the Dora was notably superior, as the aforementioned wings of the Ta 152H made it notably unstable at high speed. The H-1 carried, but was not cleared to use GM-1, nor does it seem they would have ever been supplied with the mixture. This is a discrepancy of several hundred kilograms, leaving the true climb performance of the aircraft somewhat ambiguous, with a claimed 20 m/s at sea level without MW 50.

The P-51B’s and D’s had marginal differences in performance They were among the most aerodynamically clean fighters of the war, boasting an extremely streamlined fuselage, laminar flow wings, and a radiator scoop which produced thrust that offset upwards of 90% of its own drag. To increase maneuverability in high speeds and in power dives, the control surfaces were internally sealed and used a diaphragm to reduce stick forces. The engine was a Packard Merlin V-1650-7 with an intercooled, two stage, two speed supercharger. Even though the engine was actually geared for lower altitude use than its predecessor, the combination of these features made the aircraft a very fast, maneuverable fighter which could boast of high performance at most altitude ranges.

Against the Ta 152H-1, the Mustang held to a higher top speed at low to medium altitude, better maneuverability at high speed, and far better dive performance. At extreme altitudes, the H-1 outstripped the Mustang in top speed, and across most altitudes would have had better low speed maneuverability. The high aspect ratio wings of the Ta 152 both gave it better handling at high altitude, and much improved stall characteristics over its predecessors down low. Curiously enough, both the Ta 152H and the Mustang were far more maneuverable than their wing loading would suggest, a result of high aspect ratio and laminar flow wing designs, respectively. However, in the Ta 152’s case, this came at the cost of a slower roll rate, and unstable high speed dive characteristics. While the Ta 152H could prove an exceptionally challenging high altitude opponent to all of the contemporary Allied fighters, it was a competitive, but not particularly impressive aircraft at lower altitudes. Performance wise, it could be said to fly like a more maneuverable, if slower, Fw 190D when at lower altitudes.

There is of course the story of Kurt Tank himself escaping a pair of P-51’s at low altitude in a Ta 152 prototype. Near the end of 1944, the designer himself was flying one of the prototypes to a conference in Cottbus, Germany, where he was happened upon by two P-51’s. Using the MW 50 boost system in the aircraft, Tank slipped away from his pursuers and arrived in Cottbus unscathed. Some laud this encounter a sign of the aircraft’s superiority, however, it is not a useful measure of the performance of any of the combat models of the aircraft. At Kurt Tank’s instruction, the prototype in question was unarmed and, more than likely, carrying no armor plate, which would have made the aircraft substantially lighter than any operational Ta 152H fighter.

The Spitfire Mk 21 represented the final evolution of the wartime Spitfire, by then nearing its tenth year in the air. A far echo from the Mk I, the 21 featured a vastly more powerful Griffin 61 engine. Much like its late Merlin powered predecessors, it possessed an intercooled, two stage, two speed supercharger. Unlike them, it was massive and much more powerful. After incorporating structural improvements and modifying controls for high speed, the Spitfire aged perhaps the best of any fighter of the war. Compared to the Ta 152H, it lacked the sheer distance in top speed performance of the P-51, but more than challenged the Focke-Wulf in linear speed and climb rate across most altitudes. However, at and above 7 km, the 152H had a confident advantage in speed and maneuverability.

The P-47N represented the final evolution of the Thunderbolt. Though not destined for Europe, it performed similarly to the P-47M which debuted in combat roughly the same time as the Ta 152H. (wikimedia)

Compared to the most modern Allied high altitude fighters, the Ta 152H lost most of its edge. The P-47N and M represented the final evolution of the American high altitude fighter, featuring a new 2800 hp, R-2800 turbocharged engine, and a variety of aerodynamic improvements to increase control at high speed. By the late Summer of 1944, the Western Allies had already gained air superiority over Europe, and so the new aircraft was stockpiled in the US for use in the Pacific, with the first deliveries being made in September of 1944. There was a similar performing model in Europe, the P-47M, though it was a limited production aircraft designed for chasing V-1 flying bombs and other high speed targets. Teething issues would keep it from entering service roughly until the Ta-125H did, in March of 1945. In the end though, the Luftwaffe had become so degraded that clearly no new updated models would be required and the performance increases would not justify the effort to refamiliarize pilots and maintenance personnel.

In terms of top speed, the P-47M&N handily outperformed the Ta 152H at all altitudes, the only exception being at extremely high altitudes when the Ta 152H employed GM-1. In contrast, the Focke-Wulf enjoyed a better climb rate and was likely the more maneuverable of the two, although it was certainly less capable in a dive. The late war Thunderbolts were certainly the fastest high altitude fighter which saw combat, the Ta 152H’s of JG 301 never having carried GM-1.

The P-38L was the last fighter variant of the Lightning fighter, the first model having been in service prior to the US entry to the war. With its turbo supercharged Allison engines, it was among the first fighters of the war that was designed for high altitude use. However, by the end of the war, it left something to be desired in terms of both its top speed, and like the Ta-152H, its high speed dive performance. Its low critical Mach number meant that the plane encountered compressibility at lower speeds than all of the fighters presented here. At high speeds and altitudes, the plane locked up and would remain uncontrollable until its high speed breaks were deployed, or it had descended into lower, denser air. Of all the Allied high altitude fighters, the Lightning compared fairly unfavorably with the Focke Wulf.

Most easily glossed over is the performance compared to jet fighters, which by the time the Ta 152H was introduced, could not exactly be called new. The Messerschmitt 262 had re-entered service in November of 1944 after earlier operational problems, and once training and maintenance programs were revised, the plane quickly proved itself. While it was slow to accelerate and climb, it was unapproachable in terms of top speed. Extreme high altitude use of the temperamental Jumo 004 turbojet engine was limited, though as a means of attacking high altitude formations of Allied bombers, it was by far the best equipped aircraft Germany possessed. Its slow acceleration meant that any energy-demanding maneuvers were largely off the table, but when flown by a pilot that understood its strengths, the plane was untouchable save for when it was taking off or landing. Though largely an issue post war, the Me 262 demonstrated the difficulty in justifying further piston engine fighter development at this point in aircraft development.

The Ta 152H began production after the Me 262 jet fighter had already entered service, so it, and many other programs, had to compete with it for resources. As the turbojet was already showing to be the future of fighter design, the Ta 152 was difficult to sell to the Luftwaffe. (I.PINIMG)

Overall, the Ta 152H certainly was not a Wunderwaffe by any means. At all but the highest altitudes, the aircraft was not a particularly better performer than its preceding, and much more numerous, Fw 190D counterpart. Even at extreme altitudes, it more than had competition in the form of the Thunderbolt N and M, which not only outstripped it in performance in a number of areas, but beat it into production by several months. It’s only truly exceptional performance was achieved using a high altitude engine boost system that was never made available to the unit carrying the aircraft, and in any case, it would have required a redesign of the aircraft to be used properly. Nevertheless, it represented a stark improvement in high altitude performance over previous German fighters. It too, could boast of extreme maneuverability at high altitudes, even if it didn’t lead the pack in pure speed. Top speed aside, its wings lent it a great degree of maneuverability at high altitude, and its overall performance at and above the altitudes Allied bombers flew at was considerable. This is also to say nothing of its trio of cannons; two 20mm MG151/20’s and its single 30mm MK108, which leant it incredible striking power. While the incorporation of the Jumo 213E, MW 50, and on paper, GM-1, did not produce the pinnacle of fighter design, the result was still a capable high altitude interceptor capable of engaging the highest flying targets of its day.

Construction

The construction of the Ta 152H’s fuselage was essentially that of a modified Fw 190A-8. The fuselage was largely the same with the following modifications: the forward fuselage was lengthened by 0.772 m in order to fit in a Mk 108 autocannon, the wing connecting section was moved forward 0.420 m to correct for the center of gravity, and the rear fuselage was lengthened by 0.5 m. The leading edge of the tail was exchanged for that on the Fw 190C, being considerably larger. Given the deteriorating situation near the end of the war, the new tail surfaces were wood, rather than metal skinned. The fin and rudder were enlarged for better control, with the new surface area of the tail stabilizers measuring 1.77 m2 for the vertical and 2.82 m2 for the horizontal. The changes to the fuselage necessitated strengthening, which saw some duralumin framing elements replaced with steel. In order to reduce the number of assembly jigs they needed to produce, the forward fuselage extension was bolted through the former engine attachment points.

The Ta 152H-1 featured all the fuel tanks pictured here, the preproduction H-0 had only those in the fuselage. (Deutchesluftwaffe.de)

The Ta 152H-1 featured all the tanks pictured here, the preproduction H-0 had only those in the fuselage. (Deutchesluftwaffe.de)

The wings were entirely redesigned from the Anton and changed to a high aspect model which increased the wingspan to 14.4 m, and to an area of 23.3 m2. Structurally, it remained a monocoque structure, but its rear spar and leading edge were used to absorb transverse forces and it was structurally reinforced with additional stiffening ribs. The landing gear were the same as the Fw 190A-8’s, but they were hydraulically and not electrically operated. They mounted 740 mm by 210 mm wheels to accommodate the increased weight of the aircraft. The inboard section of the wing mounted an MG 151/20 autocannon with provisions for 175 rounds of ammunition each.

Clean instrumentation, a high level of engine automation, and good visibility made the Ta 152H a fairly straightforward aircraft to fly. (destination’s journey)

The aircraft possessed a pressurized canopy to reduce the physiological stresses of high altitude flight. It was a very rudimentary system, with the cockpit rivets being sealed with DHK 8800 paste, and the sliding hood being sealed by means of a cylindrical rubber tube liner. Pressurization was regulated by means of a 1 liter air bottle supplied by a Knorr 300/10 air compressor which was geared to the engine with no intermediate gearing. The system was engaged at 8 km and maintained a constant .36 atmospheres. To prevent windscreen fogging, it was double-paned, with silica packets installed in the gap. Quality control issues saw varying effectiveness at altitude. On the record setting flight, Friedrich Schnier reported the system leaked badly above 12 km and shortly after he suffered joint pain, impaired vision, and numbness in his extremities due to low air pressure.

The Ta 152H carried an armament of two MG 151/20 20 mm cannons in each wing root and a centerline MK 108 30 mm cannon which fired through the propeller hub. The 20 mm guns were supplied with 175 rounds per gun, and the 30 mm with 90. The gunsight was the standard Revi 16b sight, which was eventually supposed to be replaced by the new EZ 42 gyroscopic sight which, when properly used, gave the pilot an accurate gunsight lead against his target. The aircraft was well armored with two engine plates, and six to protect the pilot, with a combined weight of 150 kg. The 8 mm plate behind the pilot was judged inadequate, though plans to increase its thickness to 15 mm were not carried out. A single hardpoint could be attached to the underside of the aircraft to install a 300 liter drop tank, but there were no provisions for carrying bombs.

The engine was a 35 liter Jumo 213E inverted V-12. Originally developed from the Jumo 211, which saw heavy use in bombers much earlier in the war, the new Jumo 213 was what most of the Luftwaffe’s hopes were placed on to compete with newer, more powerful Allied engines. It featured a new AJA 180 streamlined annular radiator that supported the oil and engine coolant. Critically, it was able to operate at significantly higher temperatures and pressures than older models, though not quite at the standards of the Western Allies. However, unlike Allied models, the Jumo was heavily automated. The Bediengerat, or control device, was a hydro-mechanical computer that managed the propeller RPM, mixture, supercharger speed, and radiator based on the pilot’s throttle inputs. This helped to relieve the pilot’s workload, as the Kommandogerat did on the BMW 801 powered models.

The Jumo 213E was the high altitude model which featured an intercooled, two stage, three speed supercharger. To further improve on high altitude performance, the aircraft would use a GM-1 nitrous boosting system. The system consisted of an 85 liter tank behind the pilot, and a crescent shaped liquid nitrous tank that sat at the right front side of the cockpit. The mixture was fed into the supercharger by a pump when the system was activated. As an oxygen carrier, the job of the nitrous is to provide an oxygen rich mixture to the engine when the supercharger is operating at altitudes where it is unable to provide the compression, and thus enough oxygen, needed to maintain a high manifold pressure. For the Jumo 213E, this was above 11 km. The drawbacks of the system were its uselessness below 11 km, and the bleed off of the evaporating liquid nitrous, which prevented it from being efficiently stored aboard the aircraft beyond several hours. Unlike its use on other aircraft, like Bf 109’s and Ju 88’s, the position of the nitrous tank aboard the Ta 152H proved dangerous, as it severely impacted the plane’s stability. It is unlikely the system would have been very effective without a major redesign of the fuel and mixture tanks, as even with a ballast kit that stabilized a GM-1 carrying plane, the aircraft could not carry anywhere near its full fuel load or its MW 50 boost system. While, on paper, the system promised unparalleled performance at extreme altitudes, it was almost unusable given its unstable configuration.

The MW 50 system was the low altitude boost system. It consisted of a 70 liter tank in the port wing containing MW 50, being roughly 49% methanol and 49% water, with the remainder being an anti corrosion measure. When active, the solution was pumped into the supercharger. The system was designed to boost engine power and overcome the less than ideal quality of German aviation fuels. Poor detonation characteristics, especially of the lower octane B4 fuels, forced the Germans to run at lower manifold pressures and thus lower power to avoid damaging their engines. Methanol boosted the octane rating of the fuel-air mixture entering the manifold, and the water cooled the mixture, with both factoring to bring major improvements in engine power via their combined anti-detonation, or knock, effects. The system made its debut in the summer of 1944, and was essential in allowing the later Bf 109G and Fw 190D series aircraft to stay competitive with their Allied counterparts. However, it was not without its drawbacks. It could not be used effectively above around 6 kilometers, and it was highly corrosive, severely limiting the lifespans of corrosion prone German engines. Aboard the Ta 152, it was to be installed in either a 70 liter wing tank or a standard 115 liter tank behind the pilot.

The Jumo 213E Kraftei. The entire assembly was bolted to the front of the fuselage and streamlined engine swaps. (ta152.de)

The engine had a bore and stroke of 150 mm and 165 mm, a compression ratio of 6.5:1, and a dry weight of 1040 kg. It differed from the standard model in that it had a slightly smaller bore, and the larger supercharger assembly and the associated intercooler added some 300 kg. It used B4 fuels which had a minimum octane rating of 87. The engine drove a constant speed 3.6 m VS 9 wooden propeller with a reduction gear of 1:2.40, and produced a maximum of 1753 PS (1729 hp) at sea level and 1260 PS (1242hp) at an altitude of 10.7 km. The oil header tank sat atop the front of the engine, and the coolant tank sat at the rear. On the Jumo 213A, these had a capacity of 55 and 115 liters respectively. The entire engine assembly was a Kraftei, or power-egg, consolidated unit, allowing the engine and its associated coolant systems to be easily removed or added to the aircraft.

Its radio and navigation systems included the FuG 16ZY ground control transceiver to allow it to be tracked and directed from ground based stations, a FuG 25A erstling IFF, and a FuG 125 radio direction finder for beacon homing. Some aircraft were also fitted with a K 23 level autopilot to reduce fatigue when flying the aircraft at high altitudes and in poor weather. The autopilot was accompanied with a heated windscreen and a FuG 125 Hermine radio navigation system as part of the R11 Rüstzustand equipment package.

Production of the Ta 152H

The Ta 152H was introduced in an environment where all quality control measures had already been cut down for every aspect of production. The lack of skilled labor and poor materials meant that building a reliable aircraft engine in Germany had become almost impossible by the spring of 1944. Slave labor and foreign, drafted workers had become the base of the labor pool, as most of Germany’s factory workers had been drafted to fight, resulting in a sharp decrease in quality. This was not only a result of poor working conditions and the inexperience of the workers, but sabotage became widespread, especially among those pulled to work from concentration camps. Even more desperate measures began to be instituted in the summer of 1944, as the re-use of parts from salvaged aircraft became more commonplace, and engine test runs were ever more limited to conserve dwindling fuel supplies.

The first Ta 152H-0 was completed in November of 1944 after considerable delays due to several sets of blueprints being found to be inaccurate, and sets of jigs had been lost in France the previous summer. The first planes were sent to the Rechlin test center in December of 1944, while Focke Wulf considered how to accelerate production. While doing so, they were hobbled when the Jagerstab, which managed strategic fighter production, shifted more and more resources to jet fighters and older, established piston engined fighters. Ta 152H production standards continued to decline in the midst of the widespread economic collapse of Germany. Near the end of January 1945, it became almost impossible to build any more Ta 152H’s, as the decentralized production system began to collapse, the rail system became unusable, and the wing and fuselage production center at Pozen was overrun by the Allies.

By the war’s end, approximately 60 Ta 152H fighters had been completed at the Focke Wulf facility at Cottbus. The series suffered extreme quality control issues in service with JG 301, which included supercharger surging and the failure of a propeller reduction unit, which resulted in the death of a pilot. In April of 1945, the plans were sold and shipped to Japan, where unsurprisingly, there was no new production of the aircraft.

Conclusion

The sole remaining Ta 152H is in storage at the Smithsonian Air and Space Museum, where it awaits restoration. (Smithsonian)

The Ta 152H is often seen as one of the great ‘what if’s’ of the Luftwaffe, but in reality, the aircraft was a good, rather than truly exceptional fighter. While on paper, the Ta 152H was to be an incredible aircraft at high altitude, it’s rushed development, and hasty introduction into service saw it fly without the GM-1 boost system that it needed to achieve these feats, and in a rather regrettable state in terms of build quality. It stacked up well against many of the older aircraft in the theaters it fought in, like the Yak-9, Spitfire Mk IX, or the P-38L, and against its contemporary Allied rivals, it was a competitive fighter at high altitudes.

Specification:

Specification Ta 152H-0 H-1
Engine Junkers Jumo 213E Junkers Jumo 213E
Engine Output 1753 PS, 2050 PS w/ MW50 1753 PS, 2050 PS w/ MW50
Empty Weight 4031 kg
Loaded Weight 4730 kg 5220 kg
Maximum Range 2000 km
Maximum Endurance 3.3 hrs
Maximum Speed [At altitude] approximately 720 km/h [10.9 km] 760 km/h w/GM-1 [12.5 km]
Service Ceiling 15 km w/ GM-1 (estimated)
Armament 1×30 mm MK 108, 2×20 mm MG 151/20 same
Crew 1x pilot same
Length 10.82 m 10.82 m
Wingspan 14.44 m 14.44 m
Wing Area 23.3 m^2 23.3 m^2
Height 3.38 m 3.38 m

 

Variants:

Ta 152H-0: Pre-production model, no wing fuel tanks, no MW 50 provisions, GM-1 capability but never cleared for operational use.

Ta 152H-0/R11: Poor weather pre-production series with level autopilot. Most pre-production aircraft were built in this configuration.

Ta 152H-1: Production model, wing fuel tanks, 85 liter GM-1 provisions but not supplied due to operational concerns. 70 liter MW 50 low pressure system installed. Fuel tankage increased from 595 liters to 995 liters with unprotected bag tanks in wings.

Ta 152H-1/R11: Poor weather model, autopilot. Most production aircraft were built in this configuration.

Ta 152H-1/R21: Equipped with Jumo 213EB intercooled engine, high pressure MW 50 system installed. Not operational.

Ta 152H-1/R31: Jumo 213EB, ballast kit to allow GM-1 use. No MW 50 and fuel capacity restricted. Not operational.

Ta 152H-2: FuG 15 radio set instead of FuG 16. Canceled in December 1944.

Ta 152H-2/R11: Bad Weather model.

Ta 152H-10: Photoreconnaissance model based on H-0.

Ta 152H-11: Photoreconnaissance model based on H-1.

Ta 152H-12: Photoreconnaissance model based on H-2.

Illustrations

The unique paint scheme of this aircraft was an identification measure, as the plane was largely unknown to German Flak and fighter crews. It was flown in this state to a conference.

 

 

Credits

  • Article written by Henry H.
  • Edited by  Henry H. & Stan L.
  • Ported by Henry H.
  • Illustrated by Hansclaw

Sources:

Primary:

Aeroplane and Armament Experimental Establishment Boscombe Down Spitfire F. Mk. 21 LA.187 (Griffon 61) Climb and Level Speed Trials. 10 October 1945.

Einmotorige Jäger: Leistungsdaten, 1.10.44

Ersatzteil-Liste TA 152. Konstruktionsgruppe 7 Triebwerksanlage. Focke-Wulf Flugzeugbau G.M.B.H. Bremen.

Fighter Offensive Performance at Altitude Model P-47N-5RE Engine P&W R-2800-73 GP=45:1 Propeller-4 Blades- 13’0” DIA. (Curtis 836) War Emergency- 2800/2800 S.L. to Critical Altitude G.W.=13962 LBS. Republic Aviation Corporation. Farmingdale L.I., New York.

Horizontalgeschwindigkeit über der Flughöhe mit Sonderleistung. Leistungsvergleich Fw 190 – Ta 152. Focke-Wulfe Flugzeugbau G.M.B.H. 3.1.45

P-51B-15-NA 43-24777 (Packard Merlin V-1650-7) Performance Tests on P-38J, P-47D and P-51B Airplanes Tested with 44-1 Fuel. (GRADE 104/150). 15 May, 1944.

Smith F., M.A. and Brotherton J. Note on the performance in flight of the German jet-propelled aircraft Messerschmitt 262, Heinkel 162, and Arado 234. Royal Aircraft Establishment, Farnborough. October 1945.

Secondary:

Brown, Eric Melrose. Wings of the Luftwaffe. Hikoki, 2010.

Douglas, Calum E. Secret Horsepower Race: Second World War Fighter Aircraft Engine Development on the Western Front. TEMPEST, 2020.

Green, William. The Warplanes of the Third Reich. Doubleday & Company. 1970.

Harmann, Dietmar. Focke-Wulf Ta 152 the Story of the Luftwaffe’s Late-war, High-Altitude Fighter. Schiffer Military History. 1999.

Smith, J. & Creek, Eddie. Focke-Wulf Fw 190, Vol. 3: 1944-1945. Specialty Pr Pub & Wholesalers. 2015.

Smith, J. & Creek, Eddie. Me 262 Volume Two. Crecy Publishing. 2007.

Weal, John. Focke-Wulf Fw 190 Aces of the Western Front. Osprey Publishing. 1996.

Messerschmitt Bf 109G-1,3,5: Pressurized, High Altitude Series

Nazi flag Nazi Germany (1942)

High Altitude Fighter – Reconnaissance

Approximately 690 Built

The small compressor scoop behind the inertial starter is among the only features to differentiate this G-5 from its unpressurized counterpart. (asisbiz)

Introduction:

The end of the battle of Britain was the beginning of an escalating air war which would claim nearly all of Europe as its theater. While neither air force could be said to claim the Channel in its entirety, low level fighter sweeps, tactical bombing raids, and high level photoreconnisance efforts would be conducted with ever more sophisticated methods and technology over the coming years. High flying recon planes, in particular, would prove the most challenging to combat, as specialized aircraft, like the Ju 86p, began to appear alongside ever faster fighter planes equipped with cameras. With the air war quite literally being taken to new heights, it would take a considerable effort to modify existing fighter planes to enable them to deal with an enemy operating at extreme altitude. In Germany, such efforts would produce the high altitude, ‘odd numbered’ variants of the Bf 109G, which would incorporate nitrous boosting systems and pressurized cockpits to enable them to chase targets far above their unmodified counterparts.

No laughing matter

Prior to the Second World War, high altitude fighter development was a largely secondary issue, in comparison to the build up of aircraft geared for combat at low and medium altitude. The premier fighters of the battle of Britain, the Spitfire Mk I and the Bf 109E, both exemplified this, the latter possessing a single stage, two speed supercharger, and the former a single stage mechanically driven variable speed type. The performance of both aircraft declined considerably as the planes rose above six kilometers. After the battle of Britain, the once highly active theater of Western Europe became secondary to the battles waged in the Mediterranean and the East. The primary activities there soon became focused on intelligence gathering and nuisance raids; there was an escalating nightly strategic air war, however, it was largely dislocated from the efforts of both the RAF’s and Luftwaffe’s daylight forces.

The Ju 86p, with its turbocharged engines and pressurized cabin, caused great alarm among the RAF in 1940, as the peculiar looking recon plane flew at altitudes that made it nearly untouchable. (Rods warbirds)

In 1941, both sides would introduce two aircraft which would largely shape the high altitude mission, namely the Ju 86P and the DeHavilland Mosquito. Neither aircraft could be caught by the conventional models of either the Bf 109 or the Spitfire, and thus a race to design high altitude models of the fighters began. For the Germans, the process would be far more complicated, as the reduced supply of certain critical materials meant that the traditional methods of increasing performance were off the table. There was insufficient nickel for corrosion resistant exhaust valves, no tin for heavy duty bearings, and eventually, less cobalt and chromium for heat resistant alloys. On top of this, a transition to synthetic fuels would further complicate matters. While the Battle of Britain-era Bf 109E could boast of both good performance and reliability, its succeeding F model would be plagued by a number of issues, and its increased performance was accompanied with horrible mechanical reliability. In short, nickel poor exhaust valves corroded and failed and the untested C3 synthetic fuel degraded in rubber fuel tanks and escaped into the oil system. Fuel escaping into the oil system was common on most aircraft, but it often happened in small quantities that were subsequently boiled off. The droplets which failed to aerosolize in the DB 601N tended to be of a larger than normal volume, and combined with Daimler Benz engines running cooler than most, they often failed to boil off.

With the new model of Bf 109 in such a sorry state, any new major modification of the engine was forgone, and boosting high altitude performance would fall on some external system. However, the Germans already possessed and employed such a system the year before. GM-1, or Goering Mixture-1, was a nitrous oxide injection system which was used to boost the high altitude performance of a late and uncommon model of the previous aircraft, the Bf 109E-7NZ. The mixture worked as a means of delivering oxygen into the engine’s combustion cycle at altitudes where the supercharger’s boost could not supply the boost pressure to run the engine at emergency power. Additionally, the mixture had the added benefit of cooling the engine when the mixture was injected at a low temperature. Carried in bottles behind the pilot’s seat, the mixture would be pumped into the compressed air circulating in the supercharger, after which it entered the manifold. Even when the supercharger was failing to produce the compression needed, any decrease in the volume of oxygen would be offset by that which was being delivered by GM-1. However, the system was not without its disadvantages. Namely, it increased the weight of the aircraft and provided only a marginal increase in power at low to medium altitudes, where a supercharger had no difficulties in providing sufficient boost to the engine. In short, GM-1 was dead weight below an engine’s full throttle height and, thus, the system had no real place on board a general use fighter plane. Transporting the mixture was also an issue, as GM-1 had to be transported either by pipeline or refrigerated trucks, after which it was transferred to smaller bottles. As it was kept cool, it could not be kept aboard a grounded aircraft and was usually loaded aboard as part of its pre-flight preparations.

Its limitations aside, it was clear that GM-1 was the only means by which the Bf 109 could achieve the much needed high altitude performance.

One Step Forward, Two Steps Back

The trouble with the Bf 109 F’s DB 601N engine would be solved mostly by the introduction of the DB 601E. The new engine switched the fuel source to the lower octane B4, its direct injection pumps were adjusted to prevent fuel drops from entering the oil system, and some of the more fragile components of the engine were redesigned. Prior to this, the Bf 109F ran at a reduced maximum output prior to the Spring of 1942. With the restriction rescinded, it was allowed for the maximum rated manifold pressure to rise from 1.3 ata to 1.42, and it could finally run at its intended, full emergency power.

The new engines were installed aboard the Bf 109F-3 and F-4, and were largely satisfactory, but the delay in achieving their full performance was considerable. The success of the new model DB 601E meant that high altitude developments could continue, and the first new model, after over a year, was the Bf 109F-4/Z. The engine was similar to the early DB 601N aboard the high altitude E-7Z, and delivered roughly the same level of performance, however, the structural and aerodynamic improvements of the F model allowed for better handling and maneuverability. Like the earlier E-7Z series high altitude fighter, there were no standardized provisions for photoreconnisance equipment. The GM-1 system too was improved and expanded on. The tanks were moved from behind the pilot into the wings, which increased the total to 100 kg. The mixture too was stored in a chilled, liquid state which increased its potential horsepower increase from +3 bhp per gram to +4.

A Bf 109E-7Z being prepared at a frontline airfield (asisbiz)

It is difficult to ascertain the success these aircraft had, as no distinction was made between F-4 subtypes for kill claims. However, an F-4 of JG 1, a unit which did possess the high altitude variant, brought down a Mosquito at high altitude on August 19, 1942. Lieutenant Gerd Scheiger engaged Mosquito W4065 on a bombing raid to Bremen, at a height of 8.8 km. Given the extreme altitude of the engagement, it is very likely the aforementioned Bf 109 was a high altitude model.

The few Bf 109F-4Zs would serve on every front with considerable success, though access to GM-1 could be problematic across the Mediterranean and on the Eastern Front. However, these troubles were nothing compared to the issues soon to arise with the aircraft’s successor. The Bf 109G series hoped to bring a much desired increase in performance with its DB 605A engine. Effectively developed by boring out the cylinders of the preceding DB 601E, its volume and compression ratios were increased considerably. Along with improvements to its supercharger, and built with a crankshaft able to handle higher RPMs, great hopes were placed on the engine. They were soon shattered. Almost as troublesome as the DB 601N, the engine faced a variety of harsh teething issues. Worst of all were its fragile, corrosion prone exhaust valves and an insufficient oil scavenge system made worse by a switch from ball to sleeve bearings. The series would not reach its potential for almost two years, as Daimler Benz worked through these issues. However, in perhaps the clearest example of the confusing and disjointed relationship between the Luftwaffe and its contractors, they failed to ensure a continuity in materials between the engines in its development branch and those being produced for the Luftwaffe. At an RLM meeting on May 19, 1942, it was revealed that the valves on the test engines had a nickel content of 14%, while those shipped to the Luftwaffe possessed only 8%. This, and similar discrepancies delayed effective testing for some time.

Ground crew performing maintenance on a Bf 109E-7Z. (Asisbiz)

Regardless of the disasters brought on by the lower quality economy alloys, and the misadventures between the Luftwaffe and its contractors, development of the high altitude Bf 109 continued apace.

Under Pressure

The new supercharger on the Bf 109G was extremely promising, and was one of the only things that really worked when the aircraft was introduced. With it, a new high altitude model and standard fighter were produced. The G-1 and 2 were largely built along the same lines as the late F-4 series, with a series of improvements to its armor and instrumentation. The G series also incorporated a series of standardized, modular Rustsatz kits, which could represent anything from bomb racks to photographic equipment. However, these initial models brough little improvement, as they were soon prohibited from running above 1.3 ata in manifold pressure, or in other words, without an emergency power setting. However, the G-1 would prove fairly innovative thanks to a number of new features.

Of the two, the G-1 was the specialized high altitude model, which would include both the ability to carry the GM-1 system, and was equipped with a pressurized cockpit. The cockpit pressurization allowed for a pilot to remain at extremely high altitudes without encountering any of the discomfort one would otherwise experience. Without these aches, pains, and numbness, a pilot was far less likely to become fatigued after long flights at extreme altitudes. The cockpit pressurization system was rudimentary, and was kept pressurized by a compressor which drew from a small scoop left and forward of the pilot. Silica pellets were also installed in the canopy and windscreen to prevent fogging. The GM-1 system too was improved, being made modular and paired with a set of fuselage racks which allowed for the fitting of a reconnaissance camera. GM-1 would also be made available to all subsequent models of the Gustav, regardless of pressurization gear.

The compressor scoop above the supercharger intake is the only major external difference between this aircraft and the non-pressurized G-2. (asisbiz)

The first of these aircraft were built in May of 1942 at the Erla plant and were subsequently handed off for testing and familiarization with Luftwaffe crews. These planes were then used by the 11th staffel of JG 2, noted as their high altitude unit, and began operations on July 17. The unit was first based in St. Pol in the Netherlands and would be assigned to the area before later being redeployed to Germany, and then to the Mediterranean in November, and then transferred to JG 53 before the end of the year. JG 5 also received a number of the planes some weeks after JG 2, the unit being assigned to various bases in Western Europe until the end of the war. Beyond these combat units, the aircraft was operated by the training units Ergänzungs-Jagdgruppe West and JG 105.

In service, the aircraft performed well. In particular, the pressurized canopy was well regarded, and performed well enough to see its inclusion in several succeeding models of the aircraft. Curiously enough, the aircraft were not reserved exclusively for high altitude use and was instead used much like the standard version of the fighter. Their use as high altitude interceptors was more typical of the European squadrons, which had the benefit of better access to GM-1. Even then, G-1’s were still sortied to engage targets at all altitudes. Among the earliest victories came on July 11,1942, when Unterofficier Herbert Biermann engaged and downed a low level Mosquito which had attacked rail traffic near the Danish town of Tonder, after a raid on the U-boat pens in Flensburg. The plane had been damaged during the raid, which undoubtedly helped the pursuing Messerschmitt.

The Up Swing

In spite of the debacle that was getting the DB 605A into service, improvements were slowly being made. Experiments with face hardened, chrome plated exhaust valves would give way to a workable solution to corrosion, and combined with added oil throwers and a new oil centrifuge, would eventually allow the plane to run at its highest power setting. The restrictions would finally be released by August 1943, over a year after the aircraft first entered service.

At the beginning of the year, the Bf 109G-3 had superseded its predecessor. The aircraft’s largest difference, apart from its engine improvements, were its larger tires. Small bulges were added to the top of the wing to accommodate the enlarged landing gear, and the larger tail wheel was now non-retractable, adding a not inconsiderable amount of drag. These changes were made to give the aircraft better ground handling and allow it to better operate out of rough airfields in the Eastern Front and the Mediterranean.

Unlike the previous model, the G-3 saw increasing use against USAAF daylight bombing raids. The raids had started small in late 1942, often against targets nearest England. By the Summer and Autumn of 1943, the raids had escalated continuously and were increasingly focused on targets within Germany. By then, the major focus was on the so called ‘panacea’ targets, which numerous war planners thought could bring an early end to the fighting. Ball bearing and aircraft assembly plants received particular attention.

Bf 109G-3s parked among non-pressurized models. (asisbiz)

The bombers of the 8th Air Force often flew at extreme heights, with B-24’s averaging about 22,000 ft, and the lighter loaded B-17 at or above 25,000. Despite being above the altitude where most Luftwaffe fighters could not sustain emergency power, this advantage, and the heavy defensive armament of these bombers, did not translate into a sufficient defense against fighters. While the high altitude Bf 109G-3’s did have the edge, it was largely unnecessary, as the Luftwaffe only made massed attacks against the formations until after the bombers had passed over the Low Countries, where their fighter cover could not follow them. Thereafter, they were harassed by all manner of fighters, from light single-engined types, to night fighters pressed into daylight use.

In the case of the Bf 109, they followed Generalmajor Adolf Galland’s recommendation. The method involved attacking bomber formations at frontal angles in massed attacks using formations no smaller than the four plane schwarm. These attacks were conducted to help cope with the somewhat inadequate armament of the Bf 109, and to reduce the likelihood of being hit by the defensive gunners of the bomber. During a frontal attack, a bomber’s pilots and engines are the most vulnerable, which is quite important considering the single 20 mm aboard the Bf 109 was regarded as inadequate for bringing down a heavy bomber and thus needed to be directed toward these critical areas. Underwing gunpods were somewhat commonly fitted, though their impact on flight performance was considerable. The real breakthrough in anti-bomber weaponry came with the 30 mm Mk 108 autocannon, though its late introduction meant supplies were tight until mid 1944. The frontal attack also ensured the highest possible closure rate with the formation, making the small fighter a much more difficult target for any defensive gunner, and allowed the fighter to strike at the bomber’s engines and cockpit.

Large scale anti-bomber tactics employed early warning radar to track bombers during their ingress into German held airspace, and after they had passed the range limitations of their escorts, the Luftwaffe tracked the formation using trailing Ju 88’s and other long range aircraft. Fighter units would be massed over radio beacons until they received the order to attack and were vectored on to the bomber formations, where they could meet them in numbers. The height of their success was seen in Autumn of 1943, when USAAF planners were hoping to accelerate their progress on Operation Pointblank, seeking to cripple the German aviation industry. On August the 17th, the 8th Air Force prepared for its largest raid yet, with 376 B-17’s dispatched to attack the ball bearing works at Schweinfurt and a Messerschmitt factory at Regensburg. Both of these facilities were located deep within Germany and most of the journey would see the B-17’s outside the area where they could be escorted. To compensate for this, the flight over Regensburg would continue over the Alps and into Allied controlled Tunisia. It was hoped that flight over the Alps would prove easy, and in the case of the Schweinfurt force, they believed that the German fighter squadrons would still be on the ground refueling after their first attacks while the bombers made their return. Both waves would be met with disaster, as the Luftwaffe would hit both forces after their escort fighters turned for home, and the Luftwaffe fighters had taken to the air again as the Schweinfurt raiders made the return trip.

Of the 376 bombers to leave England, 60 would be shot down, 176 were damaged, and 30 remained in North Africa, where they awaited repairs at the overburdened facilities in Tunisia. Losses in combat and written off airframes amounted to 31% of the dispatched force; in contrast, the Germans lost only 28 fighters. In effect, the Luftwaffe was able to effectively deny large portions of their airspace to the raiders. A stalemate in the air ensued in the following months, with new challengers further shifting the balance of power next spring.

Wilde Sau

In addition to the typical daylight squadrons, several Bf 109G-3’s and 5’s were passed on to the single engine night fighter unit JG 300, its sister squadrons 301 and 302, NJG 11, and the first staffel of the 10th Night Combat division. The new G-5 was much the same as the 3, save for its 7.92 mm guns being swapped for 13 mm ones. Originally formed as an experimental unit in the spring of 1943, JG 300 was meant to test the suitability of single engine fighters for night interception use. The initial premise of the unit was to engage RAF bombers over their targets, where the light of the fires and searchlights would make the planes more visible against the ground and cloud cover, and thus enable interception without the use of ground control and onboard radar systems. The squadron saw mixed success and was expanded upon after the bombing of Hamburg, when the RAF succeeded in spoofing the shared frequency of Wurzburg ground based and Fug 202 airborne radar systems with chaff. The Luftwaffe would recover in the span of several weeks, though the attack made the idea of radar-less night fighting alluring.

A Bf 109G-5 nightfighter of JG 300 under inspection. The reinforced canopy hood is easily discernible here, as are the window silica cartridges. (asisbiz).

The group was expanded upon with the 301st and 302nd squadrons being established. While the hope of transitioning daytime fighter squadrons to night use was deemed infeasible due to the amount of training required, the combined unit would continue its task, being joined by a staffel of the 10th Night Combat Division. The task of carrying out the interceptions over raided cities was an exceptionally dangerous one, as they shared the space with flak units, and by the end of the year, enemy night fighters.

There was also a transition away from the unguided wild boar tactics to ground directed interception in order to deal with high flying Mosquito pathfinders and bombers, which no Luftwaffe aircraft could effectively catch until the Me 262B provisional night fighter was introduced. In this role, the single engine night fighter would be directed into a fixed ‘Himmelbett’ intercept zone which covered either the approach, or departure path of the detected enemy aircraft. There, the target would be tracked by the Himmelbett zone’s dedicated radar and searchlight units while the fighter would be guided on to the target. This was an exceptionally difficult task owing to the speed of the Mosquito, and could prove exceptionally dangerous if the aircraft being chased turned out to be a night fighter. As RAF night fighters began to escalate their intruder missions, transiting to and from interception areas became much more dangerous. While the Mosquito night fighters were larger and less nimble than the Bf 109, their radar systems allowed them to catch the otherwise “blind” daylight fighter.

This matte pale gray paint scheme was intended to reduce visibility against clouds at night, it was also standard for heavier, twin engined nightfighters. (asisbiz)

The success of these units was mixed, though some extraordinarily capable pilots achieved some very impressive results. The best of them was Lt. Kurt Welter, who by the end of the war was in command of the only night fighter unit equipped with Me 262’s. On the night of August 30th, 1944, Lt. Welter flew a Bf 109 which had been vectored over the Stettin raid area. In the span of ten minutes, he attacked four Lancaster heavy bombers, two of which were later confirmed destroyed, these being 115 Squadron’s PB131 and 12 Squadrons’s PD 273, representing his 14 and 15th confirmed victories. Most pilots, however, achieved considerably less success owing to the extremely high level of flying and combat proficiency their missions demanded. Mosquito interception duties were the most difficult owing to the speed and altitude of the light bomber, which could often exceed 8 km. To aid these pilots, a number of rare Bf 109G-5’s with high altitude DB-605 AS engines were made available to these squadrons. Nonetheless, Mosquito interception remained a gamble depending on the distance at which the bomber was detected, whether a fighter could be launched fast enough to climb, and still have enough time to be vectored into its flight path.

Crowded Skies

By the end of 1943, the newest and last iteration of the high altitude series was in service. The new Bf 109G-5 now carried a pair of 13 mm MG 131’s in the place of its 7.92 mm MG 17s, this increase being installed after long standing complaints regarding the inadequacy of the machine guns in the upper cowling of the plane. The heavier guns and the enlarged cowling meant the aircraft was slower than the one it replaced. This proved fairly concerning, as no major improvements in engine output were expected for the foreseeable future. These aircraft were distributed to units on all fronts and used much like their standard, non-pressurized counterparts. Most were deployed in the strategic air defense of Germany, where they soon faced a new, and very dangerous opponent.

The P-51B Mustang appeared to be the solution to bomber offensive’s ills, being a fast, maneuverable fighter with incredible range and high altitude performance. The danger of this new threat was quickly recognized by one Generalmajor Joseph Schmidtt, who began to advocate for the need for GM-1 equipped Bf 109s to act as top cover for the previously secure massed fighter formations. In this, the aircraft proved a mostly adequate stop gap, performing much better than other models, but it still lagged behind the American P-51B and the P-47D at altitude. In short, the Bf 109 was an old airframe, operating with an engine which had become fairly outdated after significant delays in getting it to reach its highest power ratings. Even worse, many of the airframe’s changes over the years had negatively impacted its performance, especially the addition of the non-retractable tail wheel, and the enlarged upper cowling to accommodate the larger machineguns.

A pair of Bf 109G-5’s depart. (asisbiz)

However, there were still some areas of improvement. In particular, the supercharger was swapped for an enlarged version which came from the DB 603 engine. Switching the engine entirely was completely unfeasible. The Luftwaffe’s research and development could be chaotic at the best of times, and 1944 certainly was not the ideal environment for such a big risk. The bombing raids too were making their mark as, while they had failed to curtail the German aviation industry entirely, they had forced a consolidation of existing designs. In effect, German bomber production plummeted in order to bolster production of a series of fighter designs which saw very slow modification rates. The vastly expanded use of slave labor in the following months also created no shortage of trouble, with quality slipping sharply as skilled workers were increasingly drafted into the Wehrmacht, and slaves increasingly sabotaged components.

The final models of the G-5 used the DB 605AS engine, with the much larger supercharger designed to improve high altitude performance. The effort was largely successful, though only a few Bf 109G-5’s would ever be equipped with the engine. As much as pilots enjoyed the comfort of the pressurized canopy, it was an expense that Messerschmitt and their directors at the Jagerstab were no longer willing to accept. The G-5 would be the last model to carry it. The Luftwaffe’s fortunes too declined sharply, as P-51 fighter sweeps periodically attacked airfields once considered safe, and the brutal war of attrition had eroded the number of remaining experienced pilots further. Attacks on Germany’s synthetic fuel production in the summer of 1944 introduced a final, and catastrophic crisis which largely left the Luftwaffe crippled for the remainder of the war.

G-5 production was phased out entirely in June of 1944, as Messerschmitt moved to consolidate Bf 109 production with the G-14. The supply chain would however remain disjointed, as they produced models using the standard DB605A, and the high altitude DB605AS. The G-14, with its standardized, low altitude MW50 boost system, did help reduce the performance disparity at low altitudes, with the aircraft possessing an excellent rate of climb and acceleration, but high altitude performance equivalent to the best Allied fighters would elude the Bf 109 for the rest of the war.

Handling and Flight Characteristics

With a service life beyond all other fighters of the Second World War, the Bf 109 didn’t age gracefully, but in many ways it was able to keep pace with newer models. (asisbiz)

The Gustav, as with nearly all Bf 109 models, was maneuverable, but its increased weight had made it somewhat more cumbersome than its predecessors. Initially developed to be as light as possible while carrying with it a powerful engine, the continued added weight with a comparatively little increase in horsepower resulted in control harmony compared to earlier models. Test pilots noted that while aileron and rudder forces were light, while the elevator was fairly heavy, an issue which was exacerbated at high speed. While the aircraft was exceptionally nimble at low speeds, which was well aided by the wing’s leading edge slats, heavy rudder forces and stiff elevator controls severely impacted handling at high speed. At lower altitudes, the rudder forces became excessive at around 500km/h IAS, at higher altitudes, upwards of 7 km, the controls remained lighter at higher speeds and permitted better control. Dive performance was respectable, though given that the controls were nearly seized in a high speed dive, it could prove very dangerous at lower altitudes. Maximum level speed was decidedly mediocre, though the aircraft boasted a high climb rate and good acceleration thanks to its high thrust to weight ratio.The plane was otherwise stable and, by most accounts, with good level flight performance.

This Bf 109G-6/R3 cockpit is largely identical to the pressurized model. The centerline cannon has been removed. (Smithsonian)

The cockpit was both cramped and provided exceptionally poor visibility. The deep set seat, with its heavy cockpit framing, greatly restricted the pilot’s view, especially towards the forward and rear aspects. A few late production Bf 109G-5s were equipped with the improved Erla canopy, as became standard on late war 109’s, and provided much better visibility to the sides and rear of the aircraft. The cockpit was among the smallest on any fighter during the time period. Pilots often felt it claustrophobic, which is understandable considering the centerline cannon for the aircraft rested between the pilot’s shins.

Operation of the Gustav was extremely straightforward, given the high level of automation the DB 605A possessed. The engine was controlled through a series of linkages between components which adjusted one another as the pilot adjusted the throttle lever. The supercharger, radiator, propeller RPM, and mixture were all managed automatically, though manual control was also possible. The core of these linkages was the propeller RPM, which was preset to an accompanying manifold pressure. The rest of the engine largely adjusted itself around this setting. In stark contrast to this truly modern feature, the plane still had manually operated flaps, which were retained through the end of the war. The aircraft lacked traditional trim tabs. Instead, the aircraft’s trim was set on the ground to match its cruise speed. The pilot could however correct for pitch by adjusting the angle of the horizontal stabilizer. Flying the aircraft was otherwise very convenient.

The takeoff run was fairly simple and the aircraft could easily be corrected for the torque produced by the engine. Visibility was poor on the initial run up, but given the relatively controllable nature of the aircraft, it was something pilots easily adjusted to. The same cannot be said of late war versions of the 109, which possessed engine outputs upwards of +1800 PS. Landings under ideal conditions were notably very easy, though were much more difficult in poor weather or when operating from hastily constructed frontline airfields. There was some improvement after the G-1, when the tire tread was increased, but landings and ground handling required a pilot to ensure solid directional control, as the narrow landing gear base could cause trouble.

Comparison with other single engine high altitude fighters, up to the Summer of 1944

Aircraft Speed at Sea level (km/h) Maximum speed at critical altitude, unboosted (km/h) Speed at 10 km (km/h) Maximum Output (hp)
Bf 109G-1 -Mid 1942- 506 630 at 6.6 km 640 (with GM-1) 1213
Bf 109G-5 -Late 1943- 510 620 at 6.5 km 635 (with GM-1) 1454
Bf 109G-6AS -Early 1944- 506 653 at 8.3 km 630 1415
Bf 109G-5AS w/GM-1 (estimated) -Mid 1944- 660* 1415
MiG-3 (AM 35) -Early 1941- 472 621 at 7.8 km <550 1350
Spitfire HF Mk IX -Late 1943- 529 668 at 8.5 km 651 1710
Spitfire Mk XIV -End of 1943- 583 717 at 7.6 km 706 2050
P 47D-10 -Late 1943- 535 700 at 9.4 km 692 2300
P-51B-15 w/wing pylons -Early 1944- 586 685 at 7.2 km 667 1720

*It should be noted that the Spitfire Mk XIV saw service in low numbers, and was a very rare sight until almost a year after its introduction at the end of 1943. The rest of these planes were otherwise quite common.

The MiG-3 was among the most advanced Soviet fighters, though the high altitude fighter performed poorly in a theater defined by its low altitude skirmishes. (WWII photos)

Along with the Bf 109E-7Z, Mikoyan Gurevich’s MiG-3 debuted as one of the earliest high altitude fighters of the Second World War. The MiG-3’s AM-35A engine had high compression ratios and possessed a single speed supercharger which had been geared for high altitude performance. This allowed the aircraft to achieve a respectable level of performance above 7 km. It did, however, come at the steep cost of having mediocre low altitude performance, and above 8 km, its top speed fell dramatically. The aircraft also earned a reputation of being challenging to fly, a chief issue being its minimum landing speed, which was considerably higher than other Soviet fighters. Due to the lack of action at high altitudes over the Eastern Front, the aircraft was subsequently re-equipped with the AM-38 engine, for low altitude use. Production ceased early in the war, and its assembly lines were turned over to produce IL-2s.

The British followed the Germans in developing high altitude fighters with specialized boost systems. They would go on to produce a series of pressurized, liquid oxygen boosted Spitfires, operating on a very similar set of principles as the GM-1 boosted 109s. These however, did not see as widespread a use, as they were not quite as versatile or reliable, though this is not to say they were unimpressive. The Spitfire Mk VII with a Merlin 71 and LO could reach a speed of 618 km/h at an altitude of 12 kilometers. However, owing to a lack of available information, it will not be discussed in depth here.

A spitfire Mk IX and a Spitfire Mk XIV prototype. The Spitfire’s career was nearly as long as the Bf 109’s and generally speaking, aged better, thanks to access to better engines. (wwiiphotos, asisbiz)

A more versatile high altitude Spitfire also existed in the form of the HF Mk IX, which was powered by the Rolls Royce Merlin 71. This aircraft featured an intercooled engine with a two stage two speed supercharger, which provided it phenomenal high altitude performance, along with its broad elliptical wings. The addition of the second stage allows for further compression once the first stage alone reached its limit, and the use of the intercooler increases the upper limit of compression by reducing the temperature of the air entering the manifold. This allowed the engine to be run at a higher boost and was able to maintain combat power at altitudes far higher than the previous single stage 40 and 50 series Merlin engines. In comparison to the Bf 109, the engine can be could at combat power at high altitudes without needing to worry about depleting the supply of nitrous, which at most could last 22 minutes. In comparison, the Bf 109’s DB 605A, which operated using a variable speed supercharger which, while less powerful than the intercooled two stage type, lacked the performance gaps that came with the fixed gearing of the Merlin’s supercharger. In the case of the GM-1 powered series, however, there would have been a similar gap between roughly 7 and 8 km, between the aircraft’s critical altitude and the minimum height for GM-1 use. The use of GM-1 on the later DB 605AS powered Bf 109’s would have likely allowed them to exceed these high altitude Spitfires in respect to linear speed at extreme altitude. The performance figures for the Spitfire Mk XIV, equipped with the significantly more powerful Rolls Royce Griffon, speak for themselves.

The P-47 series of fighters achieved their tremendous high altitude performance through a different method entirely, turbocharging. Much of the interior space below and aft of the cockpit was taken up by a turbo supercharging system which managed to prevent any significant loss in horsepower up to 25,000 ft. The exhaust driven turbine proved a phenomenal means of attaining high altitude performance. Like the variable speed supercharger on the DB605A, the turbo-supercharger was not dependent on mechanically geared stages and thus lacked the associated performance gaps. However, a clear drawback to the system was its complexity, as in addition to the throttle and RPM levers, there was also a turbine lever. While it was possible to link the supercharger and throttle levers together on all but the early models, this was advisable only at certain altitudes. Running the turbine at higher speeds than necessary resulted in some horsepower loss. Regardless of this, many US pilots considered the P-47 far and away the best fighter above 30,000 ft. At high altitudes, where drag was minimal, and with over 2000 hp driving it, the P-47 possessed a speed and maneuverability far greater than its size might suggest possible. Further refinements to the design saw the aircraft exceed 720 km/h above 32,000 ft (~10 km).

A P-47D and P-51B.  These were the USAAF’s premier fighters over Europe and boasted tremendous high altitude performance. (Wikimedia, National Archives)

The P-51B was driven by largely the same engine as the Spitfire Mk IX and it was eventually geared with usage at medium altitude in mind. In addition to its powerful Packard Merlin, which gave good high altitude performance, what set the P-51 above most was its extremely low drag airframe and wings. Having been designed later than most of the aircraft discussed here, it had the benefit of being able to incorporate the most recent breakthroughs in aerodynamics. Most notably, the use of laminar flow theories in its wing design, its drag eliminating radiator scoop, and its superbly streamlined fuselage, made it among the most exceptional fighters of the Second World War. Its high speed maneuverability too was largely unparalleled, as the laminar flow wing gave it an exceptionally high critical mach number, and its internally sealed control surfaces ensured effective control at very high speed. While its Packard V-1650-7 engine was geared for medium altitude use, it still outpaced both the standard high altitude models of the Bf 109 and Merlin powered Spitfire. When run on 150 octane fuel, as was more or less standard by mid-summer 1944, its performance largely matched that of the Spitfire Mk XIV, though the Griffon engine gave the Spitfire an incredible edge above 30,000 ft. Only the Bf 109G’s equipped with the DB 605AM high altitude engine could give comparable high altitude performance with the Mustang. They could both keep pace with one another above around 9km, though few of the pressurized high altitude model were built.

Production

Production of the Bf 109G began with centralizing supply chains around the Messerschmitt factory in Regensburg, and the subcontracted Erla machine factory. The escalating bombing campaign in 1943 forced a dispersion of the industry, and many components were built at dispersal sites before final assembly took place at either the Regensburg plant, the one at Erla, and later, the Wiener Neustadt aircraft factory. The Bf 109 was fairly well suited to this scheme, but nowhere near as suited as the Fw 190, which made use of much more convenient sub-assemblies. By the start of 1944, the Jagerstab was established to boost fighter production further, in order to compensate for potential losses incurred by bombing raids. They were very successful in this regard; production surged, and the average construction time of a Bf 109G declined from around 5000 hours to approximately 2500. The cost, however ,was substantial. Bomber production was cut to the bone, fighter designs were frozen over long periods, and the long standing use of slave labor skyrocketed. Bf 109G production became more complex as the war went on and the number of subtypes expanded. These would grow to G-1 through 6 and a separate high altitude series of Bf 109G-5/G6-AS aircraft. There was some consolidation between the disparate models with the G-14, though the still separate standard and high altitude models continued to complicate production and supply chains.

Messerschmitt was among the first to mass implement slave labor in late 1942, when they requested and received 2,299 inmates who were forced to work at the aircraft plant at Augsburg. They subsequently requested the construction of co-location camps for the rest of their factories. This marked a transition from skilled paid workers, who were of a dwindling number due to conscription, to a largely unskilled base of prisoners who sought opportunities for sabotage. Brutal retaliation from the SS, who managed security, and a severely declining standard of living saw rates of sabotage climb heavily as the war went on. By the Autumn of mid 1944, it was fairly common to see aircraft losses attributed specifically to sabotaged components. Other unsafe corner cutting practices became more common as well, and even saw the re-use of components scavenged from downed aircraft.

Bf 109G-1 Production

Werknummer Factory Period
10299-10318 (20) Erla May to June 1942
14004-14150 (147) Regensburg February to June 1942

Bf 109G-3 Production

Werknummer Factory Period
16251-16300 (50) Regensburg January to February 1943

Bf109G-5 Production

Werknummer Factory Period
15200-16000 ( with G-6) WNF March to August 1943
26000-26400 (mixed with G-6) Erla August to September 1943
27000-27200 (mixed with G-6) Erla September to October 1943
110001-110576 (dedicated production) Erla November 1943 to June 1944
*a total of 475 G-5s were built, at least 16 converted to G-5AS/R2 recon planes at the Erla plant in Antwerp

Construction

Much like its predecessors, the Bf 109G was a fairly conventional late 1930s fighter design, which sought to install the most powerful engine in a small, lightweight airframe.  At its fore was the engine section, mounted on a steel mount with rubber vibration isolation. The engine oil cooler was mounted to the lower engine cowling, in order to give better access to the Bosch PZ 12 fuel injectors, with the section otherwise containing all of the motor associated systems save for the coolant radiators and GM-1 boost system. Above the engine and on the port side was the compressor scoop for the cockpit pressure system, where it remained until the Bf 109G-5, whereafter it was moved to the starboard side and slightly ahead of the MG 131 fairing. The system consisted of the compressor equipped with a relief valve, an air filter, a three way cock, a pressurizing valve, a negative pressure relief valve, a compensating valve, a pressure line, and removable silica gel cartridges. These components were distributed around the engine and canopy. The system proved fairly robust and was a much welcomed addition to the aircraft. The rest of the fuselage followed a largely conventional semi-monocoque construction, aside from the landing gear, which was mounted to the fuselage and swung inward when deployed. On the G-3, the tires were increased by a width of roughly a centimeter, such that they possessed a tread of 16 cm and a diameter of 66 cm. The associated bumps on the wing tops are the only external feature that allow differentiation between it and G-1. The control surfaces at the rear of the fuselage were operated through a standard cable linkage and were fabric skinned. The incidence of the horizontal stabilizer was adjustable in flight to set the pitch of the aircraft.

Control surface and flap rigging on the Bf 109G. (Bf 109 G-2 (mit Motor DB 605) [Bedienungsvorschrift] (1942))
The cockpit was seated deep within the fuselage, in order to reduce the frontal windscreen area, though this choice drastically decreased the pilot’s visibility. The thick canopy framing made this issue worse, especially on the pressurized aircraft, which possessed reinforced beams and a non-removable armored seatback formed the rear of the pressurized canopy hood. The cockpit itself was noted as quite cramped by virtually all who flew it, offering little in the way of headspace and shoulder room, and made all the more claustrophobic by the lack of adjustable rudder pedals. At the front of the canopy was an integral 60 mm armor glass windscreen. As with the rest of the canopy frame, it contained silica to prevent condensation at low altitudes, which could then cause icing higher up. Several Bf 109G-5AS aircraft received higher visibility Erla canopies, though they lost their pressurized features. The layout of the instrumentation was clean if dense, though the pilot was aided by a high level of automation, which meant he could largely fly the plane through just the throttle lever. Raising or lowering the flaps and adjusting the stabilizer was done manually through a pair of wheels at the pilot’s left.

The plane’s elliptical wings were attached to the fuselage through a main, centerline bracket and possessed only a single mid wing spar. Connections for the hydraulic lines, which drove the flaps and landing gear, and radiator coolant lines, connected automatically when the wings were bolted to the fuselage. Each wing possessed a radiator located inboard, with airflow controlled by two outlet covers at the rear of the radiator matrix. These covers moved along with the outboard section of flaps when the plane was adjusted for takeoff and landing. The outermost rear section contained the fabric skinned ailerons. The leading edge of the wing had a slat which would extend during hard maneuvers and improve the turning abilities of the aircraft. These could prove troublesome on earlier models in regards to unwarranted deployment and jamming in place, but had been worked out by the G model.

The GM-1 system consisted of the nitrous bottles, compressed air, and the control system. On the Bf 109G, the system existed as part of a Rustzustand or Umbausatz kit which could be installed at a Luftwaffe field workshop or maintenance center, in the latter’s case. The pressurized models shared this with the standardized models, however, they differed in that the glass-wool insulated nitrous bottles were installed in the port wing, instead of in the fuselage, behind the pilot. Later models could have the tanks stored in either position. The GM-1 was kept in a chilled liquid state, which was found to provide a higher boost effect, providing +4 bhp per second per gram over the gaseous +3 bhp. The total volume of the bottles was 115 L, not counting the compressed air which was used to force the mixture through the system. The chilled nature of the nitrous did, however, bring a drawback in that it was released as it warmed and evaporated. An aircraft would need to have its tanks filled immediately before take off in order to have the longest duration. The boost could be maintained up to 22 minutes if the tanks were filled immediately before flight, falling to 19 minutes in the winter and 16 in the summer if the aircraft departed twelve hours later. In the summer, all of the GM-1 could be expended if the aircraft was left parked for two days. The weight of the entire system was considerable, at roughly 100 kg.

Use of GM-1 on the DB605A was prohibited below 8 km, where it provided little benefit, and below which the system was mostly dead weight. With the larger supercharger on the DB 605 AS, this height increased to 10 km. In the cockpit, the pilot possessed a pressure gauge and an on and off switch to control the system. Once activated, it took up to five minutes to have the greatest effect, whereafter the pilot could turn the system on or off as they pleased. At the initial activation height, the mixture could boost the top speed of an equipped Bf 109 by approximately 30 km/h and recover as much as 300 PS at high altitude.

A DB 605A mounted in a preserved Bf 109G-6. (wikimedia)

The Bf 109G-3 through G-5 carried either the DB 605A or high altitude DB 605AS, both being an inverted, 35.7 liter, V-12. The reason for it being inverted was to ensure the propeller shaft was as low as possible. This would enable the low mounted, centerline cannon to fire through the eye of the engine without its recoil seriously jeopardizing the aircraft’s stability. This was achieved through the use of direct fuel injection, which was fairly common practice in German aviation by the start of the war, though rare elsewhere. The engine also possessed a high level of automation, which let the pilot manage the engine and most of its associated systems just through the throttle lever. These were essentially a series of linkages between components that adjusted one another as the pilot increased or decreased engine power. It did not possess a true engine control unit, as was used in the BMW 801. Additionally, the engine used a single stage, variable speed, centrifugal supercharger which was mechanically driven by the engine and used a hydraulic coupling for variable transmission. The fluid coupling supercharger automatically adjusted itself via barometric control and was easily the most impressive feature of the engine, allowing it to smoothly adjust its boost as it climbed or descended. This allowed the aircraft to avoid the performance gaps otherwise encountered with engines using fixed speed settings. The engine used B4, which was originally 87 octane, as most of the C3 high performance stocks were dedicated to squadrons flying Fw 190s.

In spite of these innovative features, the engine’s performance was fairly modest for its day. It produced up to 1475 PS, though this was only possible after several major modifications which saw the replacement of the original exhaust valves for chrome plated sets, among other major modifications. The system also had its oil system improved through the use of additional oil throwers to improve flow, and an oil centrifuge to address issues with foaming. Between 1942 and late ‘43, the high power settings on almost all of these engines were disabled in order to keep failure rates manageable. The supercharger too would eventually lag behind its contemporaries, as despite its smoothness, its volume became a bottleneck. This was most apparent in any comparison to the two-stage, intercooled models of the Merlin engine. Some later models would mount an enlarged supercharger with 30% greater volume, derived from the larger DB 603. Nearly all would be equipped with an anti-knock boost system in the form of MW50 by the summer of 1944, which would boost output up to 1800 PS, though the corrosive mixture of methanol and water decreased the engine’s lifespan. Engines with the larger supercharger were designated DB 605AS, those with the boost system 605M, and those with both were 605ASMs. Several Bf 109G-5’s were fitted with the high altitude engine, though none received the low altitude boost system, for obvious reasons.

The engine measured 101.1 × 71.9 × 174 cm, had a bore and stroke of 154 mm (6.1 in.) x 160 mm (6.3 in.), and weighed 745 kg (1,642 lb). Two coolant header tanks were set to either side of the engine, while the oil tank was placed at the front. Compression ratios were 7.5/7.3:1 (left and right blocks) with B4 aviation gasoline, ratios were different using C3 fuel, though this was not used aboard this series of fighters.

Armament profile for the Bf 109G-5. Unlike the standard Bf 109G-6, it could not mount a 30 mm Mk108 cannon. (Bf 109 G-5,6 D(Luft)T 2109 G-5,6 Wa, Bedienvorschrift Wa(1943))

Early models were equipped with a pair of MG17 7.92 mm machine guns and a single, centerline MG151/20 autocannon. On the G-5, the MG17s were swapped for 13 mm MG131 heavy machine guns, which both provided a heavier armor piercing bullet, and a round with a small explosive core. While the standard G-6 could carry a centerline 30 mm autocannon, the modification was not available for any of the high altitude fighters. This was likely due to the necessary changes in the canopy required for mounting the larger weapon, which may have been incompatible with the pressurized model. As a firing platform, the 109G was excellent, especially in that all its weapons were placed at the center of the aircraft and thus required minimal adjustments for weapon convergence. However, the aircraft was very lightly armed, especially on the MG17 equipped models. Many pilots considered the armament inadequate, and the addition of supplementary underwing guns severely hampered the aircraft’s performance. These sentiments went as high as the General of Fighters, Lt. General Adolf Galland.

Conclusion

A surviving Bf 109G-1 at the Norwegian Air Museum at Sola. The other remaining aircraft is a G-5 at the Dutch Air Museum at Steppe. (Flyhistorisk Museum Sola)

The pressurized models of the Bf 109G proved to be an expedient means of boosting the performance of high altitude squadrons. The pressurized canopy, while later seen as an expensive luxury, was well appreciated by pilots who often flew at great heights on interception and photorecononniance missions. As with their standard counterparts, the series was handicapped considerably by the limitations and troublesome DB 605A. While the aircraft offered good performance for 1943, without any substantive increase in power, the pressurized Gustav series fighters began to lag considerably behind their Allied opponents the following year.

Bf 109G-1 configuration (shared with G-2) Modification type Specification
Bf 109G-1/R 1 Rüstsatz Mid fuselage bomb rack. ETC 500 or Schloss 503 A-1.
Bf 109G-1/R 2 Rüstsatz ETC 50 rack for four SC 50 bombs
Bf 109G-1/R 3 Rüstsatz 300 liter centerline drop tank
Bf 109G-1/R 4 Rüstsatz SD-2 cluster munition dispenser rack, 24 SD-2 submunitions
Bf 109G-1/R 6 Rüstsatz Two underwing MG 151/20 cannons
Bf 109G-1/R2 Rüstzustand GM-1 high altitude boost system, fuselage racks for camera fitting
Bf 109G-3 Configuration (shared with G-4) Modification type Specification
Bf 109G-3/R 1 Rüstsatz Mid fuselage bomb rack. ETC 500 or Schloss 503 A-1.
Bf 109G-3/R 2 Rüstsatz ETC 50 rack for four SC 50 bombs
Bf 109G-3/R 3 Rüstsatz 300 liter centerline drop tank
Bf 109G-3/R 6 Rüstsatz Two underwing MG 151/20 cannons
Bf 109G-3/R1 Rüstzustand Two wing mounts for 300 liter drop tanks and an ETC 500 rack
Bf 109G-3/R2 Rüstzustand GM 1 high altitude boost system, fuselage racks for camera fitting
Bf 109G-3/R3 Rüstzustand Reconnaissance aircraft conversion: Two drop tank pylons, machine guns removed, fuselage camera being either Rb 75/30 or Rb 50/30.
Bf 109G-3/U2 Umbausatz Alternate GM-1 fitting, no camera provisions
Bf 109G-5 configuration (shared with G-6) Modification type Specification
Bf 109G-5/R 1 Rüstsatz Mid fuselage bomb rack. ETC 500 or Schloss 503 A-1.
Bf 109G-5/R 2 Rüstsatz ETC 50 rack for four SC 50 bombs
Bf 109G-5/R 3 Rüstsatz 300 liter centerline drop tank
Bf 109G-5/R 4 Rüstsatz SD-2 cluster munition dispenser rack, 24 SD-2 submunitions
Bf 109G-5/R 6 Rüstsatz Two underwing MG 151/20 cannons
Bf 109G-5/R 7 Rüstsatz PR 16 radio direction finding gear, designation not usually applied
Bf 109G-5/U2 Umbausatz GM-1 boost system
Bf 109G-5/R2 Rüstzustand Rb 50/30 camera fitted

*Rüstsatz kits are removable on a mission basis, Rüstzustand are installed at workshops, Umbausatz are kits that are built into an aircraft at the factory or a maintenance and recovery center.

Aircraft with FuG 16y radio sets, for command aircraft, received a -y suffix. For example, Bf 109G-5y/U2/R 3 would be a fighter equipped with a radio set for ground control, GM-1, and an external fuel rack.

Bf 109G-1 Specification
Engine DB 605A
Output 1475 PS
Gross Weight 3050 kg
empty weight
Combat Range (internal fuel only) 668 km
Maximum speed (prior to downrating) 660 km/h at 7 km
Armament 2x 7.92 mm MG 17, 1x 20 mm MG 151/20
Crew Pilot
Length m 8.84
Height (without propeller) m 2.6
Wingspan m 9.924
Wing Area m2 21.6
Bf 109G-5 Specification
Engine DB 605A, DB 605 AS
Output (DB 605 AS) 1475 PS (1415 PS)
Gross Weight 3350 kg
Empty weight 2543 kg
Combat Range (internal fuel only) 625 km
Maximum speed (DB 605 AS) 630 km/h at 6.5 km (650 km/h at 8.5 km)
Armament 2x 13 mm MG 131, 1x 20 mm MG 151/20
Crew Pilot
Length m 8.84
Height (without propeller) m 2.6
Wingspan m 9.924
Wing Area m2 21.6
Plane In use with
Bf 109G-1 I/JG2, 11./JG2, 11./JG26, II./JG51, JG 53,
Bf 109G-3 11./JG 2, 11./JG26, I./JG1 (later II./JG11)
Bf 109G-5 III./JG 1, II./JG 2, I.& II./JG3, II./JG11, III./JG 26, II./JG27, I./JG300, I.&II./JG302, II./JG 11, II.&III./EJG 1, NAG 2, NAG 12, NAG 13, (F)/123

Credits

  • Article written by Henry H.
  • Edited by  Henry H. and Stan L.
  • Ported by Henry H.
  • Illustrated by Hansclaw

Illustration:

Bf 109G-1 of JG2 flown by Julius Meimberg, WNr-14063 Poix, France November 1942.  The G-1 was beset with serious teething issues, but even with engine restrictions, its high altitude performance was exceptional for its day. The G-3 saw these limitations removed, though its tail wheel was non-retractable. It should be noted that the tail wheel on this G-1 was semi-retractable.
Bf 109G-5, 1944. The G-5 was better armed than its predecessors with its 13mm machineguns, but this came at the cost of added weight and drag.
Bf 109G-5, JG 300, 1944. A number of G-5’s were turned over to night fighter squadrons using both Wilde Sau free roaming tactics, and Himmelbett directed interception against high altitude Mosquitos. The non-reflective, gray camouflage was also standard on twin engine night fighters.
Bf 109G-5AS of JG 5, flown by Hauptmann Theodore Weissenberger, June, 1944.  The Bf 109G-5AS incorporated a larger supercharger that required an enlarged engine cowling. Further modifications included the much improved Erla factory canopy, and a larger horizontal stabilizer and rudder. These were very rare aircraft and used mostly for reconnaissance and high altitude Mosquito interception.

Sources:

Primary:

Bf 109G-2 Flugzeug Handbuch (Stand Juni 1942).Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. November 1942.

Bf 109G-4 Flugzeug Handbuch (Stand August 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. September 1943.

Bf 109G-2 Flugzeug Handbuch (Stand August 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. October 1943.

Flugzeug Flugleistungen Me 109G-Baureihen. Messerschmitt AG Augsburg. August 1943.

Daimler-Benz DB 605 Inverted V-12 Engine. National Air and Space Museum Collection. Inventory number: A19670086000.

Flugzeugmuster Bf 109 G-1 mit Motor DB 605A. Rechlin E`Stelle Erprobungsnummer 1586. 1943.

Memorandum Report on P-47D-10 Airplane, AAF No. 43-75035. Army Air Forces Material Command. Wright Field Dayton, Ohio. 11, October 1943.

The performance of Spitfire IX aircraft fitted with high and low altitude versions of the intercooled Merlin engine. Aircraft and Armament Experimental Establishment Boscombe Down. 4 March 1943

Leistungszusammenstellung Me 109G. Messerschmitt AG. Augsburg. 1 January, 1944.

Leistungen Me 109G mit DB 605 AS. Messerschmitt AG. Augsburg. 22, January 1944.

Leistungsmessung Me 109 G mit GM 1 – Zusatzeinspritzung. Messerschmitt AG. Augsburg. 21, September 1943.

Me 109 G-1. Ausführung. Messerschmitt AG. Augsburg. 21 May, 1942.

Speed vs Altitude P-51B-15 43-24777. Flight Test Engineering Branch Memo Report No. Eng-47-1749-A. 20 May 1944.

Kurz-Betriebsanleitung für Flugzeugführer und Bodenpersonal für GM 1-Anlagen in Bf 109 G. E-Stelle Rechlin R 3 a 1.

Me 109 G DIMENSIONS, WEIGHTS AND PERFORMANCE. A.I.2(g) Report No. 2142. 31, December 1942.

Spitfire F. Mk. VIII(Conv) (Prototype Mk.XIV) JF.319 (Griffon RG5SM). Aeroplane and Armament Experimental Establishment Boscombe Down. 27 October 1943.

Power Boosting By Liquid Oxygen and Nitrous Oxide Injection On Spitfire & Mosquito Aircraft Respectively. Engineering Report. Eng. 8723.

Secondary:

Douglas, Calum E. Secret Horsepower Race: Second World War Fighter Aircraft Engine Development on the Western Front. TEMPEST, 2020.

THE EFFECTS OF POOR QUALITY ASSURANCE DURING GERMAN AVIATION MANUFACTURING ON THE LUFTWAFFE DURING WORLD WAR II. MICHAEL J. GALLANT, MAJOR, UNITED STATES MARINE CORPS

B.A Florida State University, Tallahassee, Florida, 2006.

Radinger, W. & Otto W. Messerschmitt Bf 109F-K Development Testing Production. Schiffer Publishing. 1999.

Prien J. & Rodeike P. Messerschmitt Bf 109 F,G, &K Series An Illustrated Study. Schiffer Publishing Ltd. 1997.

Mosquito Fates, based on AirBritain files. Donated files, Mossie.org.

Lockheed S-3 Viking

United States of America (1975)

Anti-Submarine Warfare Aircraft; 188 built, 160 upgraded to S-3B

An S-3 Viking comes in to land on the aircraft carrier USS Independence. [National Archives]
The Lockheed S-3 Viking was an anti-submarine warfare aircraft designed to replace the aging S-2 Tracker, later becoming one of the most important components of the US Navy’s anti-submarine strategy during the late Cold War. Designed in anticipation of modern Soviet Nuclear submarines, the Viking could boast of a host of cutting edge sensors and computerization that put it well above the curve, and all wrapped up in an airframe that was reliable and versatile. Its exceptional anti-submarine capabilities were augmented even further during its mid-life improvements which lead to the introduction of the improved S-3B. After the Cold War, the aircraft transitioned away from its traditional anti-submarine duties to surface surveillance, signals intelligence, and aerial tanker duties. A thoroughly reliable and advanced aircraft, the Viking easily ranked among the most important and versatile aircraft to ever serve aboard US carriers.

The Modern Submarine

The submarine of the Second World War was little more than a long range torpedo boat with the ability to submerge itself for short periods of time to avoid detection. Its offensive capabilities were rather modest, and apart from some outlying, but considerable, success against warships, it was typically seen as a tool for disrupting overseas shipping. Their comparatively low speed coupled with the need to transit on the surface for long periods, which snorkels could not entirely eliminate, would see them become a supporting vessel of most navies. However, advancements near the end of the war would transform the submarine from a raider and reconnaissance vessel, to one of naval warfare’s principal combatants.

Owing to the extreme desperation of the German U-boat force, a submarine built along new, revolutionary lines was designed. As the surface proved an exceptionally dangerous place to be, due to long range Allied patrol aircraft, the new boat would be designed to operate almost entirely submerged for the duration of its patrols. The new Type XXI was designed around the most modern features of any submarine thus built, featuring a much improved pressure hull construction, partially-automatic torpedo loading, a powerful sonar array, and a massive battery capacity which, combined with a hydrodynamically clean hull, allowed it to travel at double the speed of a conventional Type VIIC with over three times the range.

A Type XXI submarine ready to be assembled from prefabricated sections. Massive quality control problems prevented any hope of the submarine’s use in the Second World War, though this construction process was improved post-war world wide. [national archives]
The Type XXI only completed a single wartime patrol, but its effects on naval engineering and submarine design were dramatic. In effect, every submarine built before it was obsolete, effectively restarting a new naval arms race. In the context of the then brewing Cold War, this was the cause of no shortage of anxiety for Western Navies. While the Soviet Union’s shipbuilding capabilities were relatively meager, and greatly damaged during the war, their experience with the new German submarine could very well allow them to leap up to the position of the world’s most prominent navies, if only in the field of submarine design.

In addition to the new submarine’s capabilities, the Type XXI also demonstrated that submarines could also be built at an unheard of rate thanks to its modular construction. Submarine sections could be constructed at secondary factories before being shipped to main construction yards, where they would be assembled into completed boats. Initially, an intelligence survey estimated that the Soviet Union could have as many as 2000 modern diesel-electric submarines in 1960. However, a much more reasonable secondary survey noted that they were likely restricted to 400 boats, owing to available dockyard space, fuel, and bottlenecks in battery maintenance and production. Regardless, the US Navy began work on a modernized anti-submarine strategy to counter a potential flood of Soviet boats which could threaten intercontinental supply lines in a potential war.

The first Whiskey class submarines were only marginal improvements on their WWII era predecessors. Late models, pictured here, had snorkels and performance somewhat below the German Type XXI, but with hundreds made in a relatively short time, their numbers helped offset these deficiencies. [US Navy]
The first of the new Soviet boats was the Project 613 ‘Whiskey’, a somewhat shrunken derivative of the German Type XXI. It had more modest performance than the German boat in regards to speed, range, and endurance, but once it received a snorkel on later models, it had the same ability to remain underwater for long periods. The Whiskey was thus the most advanced submarine the Soviet Union had yet built. In countering these submarines, the US Navy would employ a modified version of the same strategy it had used in the Second World War. The primary anti-submarine weapon was to remain the airplane, in the form of long range patrol aircraft, like the P-2 Neptune, and carrier based planes, like the new models of TBM-3 Avenger. Their primary means of locating submarines were radar, which could detect snorkeling submarines, magnetic anomaly detectors, which were set off by a submarine’s magnetic signature, and sonobuoys, which determine the position of a transiting submarine if dropped close enough. Radar was the main means of detecting a submarine at range, with the other two systems being used to ‘fix’ its location before attacking with torpedoes and depth charges.

Unlike their land based counterparts, early carrier based ASW aircraft lacked the ability to carry both the sensors and weapons needed for the task and were thus placed in a pair of cooperating aircraft. The first such pair were the TBM-3W ‘warning’, for detection, and TBM-3S ‘strike’, for carrying out attacks on marked submarines. These hunter-killer teams operated aboard modified escort carriers and later switched to fleet carriers, when it became clear the small escort carriers could not reliably launch and recover the larger hunter-killers. In the early 50s, it was recognized that the entire system was extremely clumsy and would not provide adequate anti-submarine support.

The Hunter-Seeker ASW method proved far too unwieldy for further use. This ‘hunter’ Grumman Guardian has a search radar on one wing and a high powered searchlight under the other. Its torpedo was stored internally. These were the largest single engine piston aircraft in service at the time of their introduction. (US navy)

The CVS program was thus introduced, which brought several mothballed WWII era-fleet carriers back into service as dedicated anti-submarine warfare ships. The CVS’s, which were introduced in 1952, were soon joined by the S-2 Tracker two years after. The Tracker was large enough to carry both the sensors and the weapons, and the clumsy hunter-killers were finally dispensed with. The S-2 was an excellent ASW aircraft which would go on to serve in a number of roles, though by the mid 60s, the growing capabilities of Soviet submarines and operational troubles with operating a piston engined aircraft on increasingly jet dominated carriers began to highlight the need for a replacement.

The Soviet Nuclear Submarine

Through the 50s and early sixties, the existing strategies for sub hunting were predicated on the need for submarines to recharge their batteries, and that said batteries could be discharged during a drawn out search, thus rendering the submarine helpless. Advancements in Soviet nuclear engineering would end up negating most of these existing strategies. General Secretary Iosif Stalin would formally sign off on the program to build the first Soviet nuclear submarine in 1952. The boat was to be a delivery platform for a gigantic nuclear torpedo for use against harbors. It was completely impractical, and due to the extreme secrecy surrounding it, was rejected by Soviet Admiral Kuzntetsov upon learning of it. The Project 672 Kit (NATO reporting sign November) was then given a conventional torpedo armament and went out to sea in 1958. It was a fast boat, with a given maximum speed of 28 kts, but its turbines proved unreliable and its reactor developed leaks after 800 hours. Less concerning was its noisiness, a factor Soviet submarine designers felt was less important than top speed, and a design choice that would plague Soviet nuclear submarines into the 1970s.

The nuclear submarine was a far more capable and deadly opponent compared to its diesel electric counterparts. Without needing to rely on electric power for underwater propulsion, a nuclear submarine was not restricted to a small patrol area, nor did it need to expose itself to detection to recharge. Furthermore, it was fast. As loud as the Novembers were, they were nearly twice as fast as contemporary diesel electric submarines. Lastly, their larger size enabled them to carry larger, more sensitive sonar systems and greater complements of weapons. In short, it was a faster, more alert, and better armed threat than anything the US Navy ever had to contend with.

The Novembers proved to be a wake up call to the US Navy, but their operational restrictions kept them from being perceived as a massive threat. For instance, they were not deployed to the Caribbean during the Cuban missile crisis, as the distance was deemed a hazard. The turbines aboard these boats were unreliable, and there was no wish to have their most advanced submarine being seen under tow. Subsequent developments would however be a more considerable concern to the US surface fleet. General Secretary Nikita Kruschev’s plan for the Soviet Navy was to be one that was capable of defending its own coasts using light warships armed with anti-ship missiles, and submarines which could stalk shipping lanes for enemy vessels. As opposed to Stalin’s views, Kruschev’s plan heavily favored the development of cruise missiles and submarines over a balanced fleet, and largely handicapped the development of larger warships.

The torpedo shaped November class was a massive, if clumsy, step forward for the Soviet Navy. While unreliability and loud acoustic emissions plagued these boats, they showed the promise of nuclear submarines to future Soviet naval planners. [US Navy]
The immediate products of this philosophy were the Echo class nuclear submarines, and to a lesser extent, the conventional Juliet class. These new boats carried heavy, anti-ship cruise missiles and were initially considered a serious threat to US carriers. They were not, however, without serious limitations. They required cooperating patrol planes to share radar data for over the horizon targets, and needed to stay on the surface for up to thirty minutes before carrying out the attack with their long range missiles. They were accordingly extremely vulnerable when operating in areas without a substantial Soviet air presence. The more advanced Charlie class materialized after Kruschev’s fall, and was capable of submerged launches, but of slower and short ranged missiles. With Kruschev gone, the Soviet Navy largely abandoned any plans of Atlantic convoy raiding to pursue building better defenses against American Polaris missile subs, and later to focus on denying potential enemies access to bastions where their own SSBNs patrolled. Largely under Admiral of the Fleet Sergei Gorshkov’s direction, the Soviet fleet would try to right itself to become a more balanced force, so that it might better assist Soviet foreign policy, and to build up a defense against wartime incursions from enemy aircraft carriers and modern nuclear submarines.

In spite of the limitations of the Soviet nuclear submarine fleet of the sixties, their growing capabilities would prompt the US into developing their anti-submarine forces even further. Throughout the sixties, new aircraft ASW tactics were employed to replace the old snorkel-chasing methods. A greater focus was placed on the use of sonobuoys, which could be used to survey larger patrol areas, and the newer versions of which were growing ever more sensitive and sophisticated. Greater coordination with surface vessels was also employed, with newer destroyers and frigates mounting considerably more powerful sonar systems. Overall, US nuclear subs would take up an ever more important role in anti-submarine warfare, massive new hydrophone lines were laid in strategically important areas, and the aircraft carrier was soon to take a primary position in anti-submarine strategy.

Viking

In the world of the nuclear submarine and the jet carrier air group, the S-2 Tracker was becoming an ever more inconvenient asset. As carriers began to carry an ever greater number of jet aircraft, there was some frustration with having to still carry stores of aviation gasoline for the S-2s. The situation was not improved by the retirement of the WWII era converted CVS, which would be entirely out of service by the early 1970s. As a result, the entire surface ASW framework was to be restructured. Among the earliest moves was to announce a competition for the S-2 replacement in 1964, under the designation VSX. The new plane was required to have at least twice the speed, twice the range, and twice the ceiling of the aging Tracker. Lockheed was among the most promising entrants due to their previous history in designing maritime patrol aircraft, though their lack of experience with carrier based aircraft saw them partner with LTV Aviation, and the new ASW gear was to be designed by Univac Federal Systems.

A wooden mockup of Lockheed’s entry into the VSX competition. [US Navy]
Lockheed’s Viking was a robust, high wing aircraft which featured a pair of turbofan engines for their power and fuel economy. The plane also carried nearly every modern airborne submarine detection system of the time. Its four crewmen operated the aircraft’s systems in coordination with a central, general purpose digital computer, which greatly aided the crew in processing the information gathered by the aircraft’s sensors. Further crew integration was accomplished through the use of multi-purpose displays that could show information from any of the aircraft’s crew positions. In addition to the MAD, radar, and sonobuoy systems, the plane was equipped with a FLIR system mounted to an extendable turret which was capable of detecting snorkeling, or near surface submarines and sea mines. To complement its sensors, the aircraft had a maximum speed of approximately 429 kts, a ceiling of 40,000 ft, and a maximum endurance of over six hours. Of the entries from Grumman, General Dynamics, and Convair, Lockheed’s design won out.

They were formally awarded the contract in 1969. The first of eight YS-3A prototype and pre production aircraft flew only three years after the contract was finalized in 1972, with the aircraft entering service two years later. This program was also the first to have a formalized set of milestones to ensure costs were kept low and technical risks were reduced. All program milestones were met ahead of schedule, and the plane was prototyped, built, and delivered in quantity in only five years. Their carriers too were modified to better suit ASW operations. In 1971, the USS Saratoga was the first to receive an ASW analysis center and support shops for ASW gear and weapons. All carriers but the older, smaller Midway class were able to receive the improvements. Prior to the introduction of the Viking, carriers operated S-2’s, with the introduction of the new aircraft vastly improving the anti-submarine capabilities of US carrier battle groups. The plane could perform an ASW search quickly at 35,000 feet at a speed of over 300 kts, a massive improvement over the S-2’s 135 kts at 10,000 ft. Even before considering the massive improvements in sensors and the centralized computer integration, the Viking could patrol truly massive stretches of ocean for a plane of its size. With a payload of four lightweight torpedoes and 60 sonobuoys, the Viking could fly out 826 nmi from its carrier, and conduct a two hour search before having to return. The use of external stores and airborne tankers could push this already phenomenal range out even further.

The unified CV concept brought together the anti-submarine and surface distinctions, as the old sub-hunting legacy carriers began to be decommissioned. The carrier’s air wing was tailored to its deployment goals. [US Navy]
VS-21, the first S-3A squadron, was deployed aboard the USS John Fitzgerald Kennedy in the summer of 1975. During its Mediterranean deployment, the Kennedy was able to truly demonstrate the universal carrier concept. Previously, carriers were divided between the CVS, sub hunting carriers, and the CVA’s, which hunted everything else. The introduction of the Viking enabled the consolidation of all US carriers into CV’s, the new concept seeing carriers equipped for every conceivable mission. However, the S-3A was not the only newcomer to the ASW mission. The year prior to its first deployment saw the introduction of the Kaman Sh-2F Seasprite. This light anti-submarine helicopter would soon be found aboard most US warships, extending both their maximum search and offensive ranges. In short, the US surface fleet’s ASW capabilities had been thoroughly improved through the adoption of these two aircraft, well in advance of the predicted improvements in Soviet nuclear submarines.

An A-6 Intruder and S-3A Viking overfly a surfaced Project 641 ‘Foxtrot’ class submarine. These boats had improved fire control and sensors over the older Whiskey and Zulu class boats, but were otherwise built along the same post-WWII lines. Significant improvements in regards to quieting and hull form would not be achieved until the later Project 641B ‘Tango’. [US Navy]
In service, the S-3A was primarily a screening element for the carrier group and any surface groups it might be supporting. A US carrier group is typically deployed alongside independent surface action groups and nuclear submarines, these often being the outermost defenses for the carrier group. The carrier’s offensive range and ability to survey thousands of miles of ocean make it the center of naval operations, and the most well defended asset. It was the job of the outer forces to screen the path and potential approaches to the carrier from enemy submarines, and to a lesser extent surface ships, though those more often fell under the purview of other aircraft and vessels.

Given the distance between these forces, gaps inevitably form, and these areas are typically patrolled by aircraft. In wartime, the Viking could quickly fly out to these locations and deploy a grid of sonobuoys, which it could maintain for several hours before being relieved by other aircraft. In addition to screening the path of the carrier, the S-3A could also be tasked to patrol the open ocean to search for older cruise missile submarines, which had to surface for long periods to fire their weapons. The S-3 would eventually receive Harpoons for this role, but initially, it would carry Hydra 2.75 inch rockets or unguided bombs. By the late 70s, these submarine ‘Shaddock’ missiles were easily defeated by the new EW systems and defensive weapons added to destroyers, cruisers, and carriers, but they still posed a threat to lighter warships and shipping. In addition to open ocean patrols and barrier searches, the Vikings could be quickly dispatched to support patrolling frigates and destroyers which were tracking submarines.

While the Victor class boats were primarily designed around the anti-submarine mission, they could fire salvos of two heavy weight, long range Type 65 torpedoes for use against large surface groups. The boat first entered service in 1977 and represented a major success in achieving low acoustic emissions in Soviet submarine design. [US Navy]
Though the Soviet fleet consisted of a large number of these older submarine classes, new models of Soviet nuclear submarines would pose a greater challenge. A change in design philosophy would see a shift in focus away from achieving the best possible speed, to a balanced approach which placed greater importance on lower acoustic emissions. When commissioned in 1974, K-387, a Project 617RT ‘Victor II’, was the first Soviet nuclear submarine to incorporate rafted equipment. With its turbines suspended on vibration dampening mounts and its hull clad in anechoic rubber tiles, it was remarkably quieter than its forebearers. Further improvements to this class resulted in the Project 617RTM ‘Victor III’, with the first boat being commissioned in 1978. However, sound reduction was only marginally improved, with much of the focus being placed on new sensors, with the main mission for the sub being ASW. With 48 total Victors of all classes being produced, it represented the modern workhorse of the Soviet submarine force. More concerning to the carrier, however, were the successors to the Echo and Charlie class SSGN. The Project 949 ‘Oscar’ was a massive vessel which carried 24 P-700 ‘Shipwreck’ missiles, three times as many missiles as the Echo. Capable of submerged launches and engaging surface targets at long range, the Oscar lacked the handicaps of the earlier boats, and its state-of-the-art missiles boasted high speed and countermeasure resistance. A single Oscar could put the air defenses of a carrier battle group to the test, and thus long range anti-submarine screening became key for naval planners. The character of the Soviet submarine force of the eighties was rather peculiar, being composed mostly of obsolete to somewhat up to date vessels, but with a small and growing pool of cutting edge submarines.

Vikings among A-7 Corsair II and A-6 Intruder strike aircraft aboard the nuclear aircraft carrier Dwight D. Eisenhower, 1980. [National Archives]
These ever-advanced models of Soviet submarines were anticipated and largely matched by the US Navy’s efforts to build a defense against them. All new warships possessed powerful new sonar systems and light ASW helicopters, and the carrier based S-3A sat at the center of fleet-wide anti-submarine strategy.

Into the 80s

While the S-3A proved an incredible new addition to the fleet, it soon encountered an unexpected challenge. As a result of the post-Vietnam defense cuts, the spare parts program for the Viking was among the worst affected. Stocks of replacement parts began to grow tight by 1977, though they would not pose a serious issue until the turn of the decade. As a result of stricter rationing of components, the mission readiness level of the Viking squadrons often fell to below 40% in 1981. However, the problem was soon identified and the procurement of more replacement parts began the following year, along with a new series of maintenance programs to increase readiness. Thanks to these efforts, the mission readiness of these squadrons climbed to 60% in 1983 and rose to 80% in the coming years, the highest in the fleet.

While the Navy was procuring additional parts, they also initiated a program to drastically improve the offensive and sensor capabilities of the aircraft. The Weapon Systems Improvement Program would seek to prepare the S-3 Viking for its service into the new millennium. Most of these improvements were focused around the aircraft’s sensor systems, most notably its new inverse synthetic aperture radar, which boasted a much higher capability in regards to periscope and snorkel detection, and its acoustic sensor suite. The acoustic data processor was improved through the use of a standardized naval signal processor which ran on a software shared among new naval maritime patrol aircraft, a new sonobuoy receiver boosted the available channels from 31 to 99, and it received a new, more reliable tape recorder for storing gathered acoustic data.

An S-3 passes a Kilo class submarine. While much of the Soviet diesel-boat fleet consisted mostly of obsolete classes like the Foxtrot and Romeo into the 1980s, the Kilo was thoroughly modern. [The Drive]
In addition to its sensor improvements, the Viking received the new ALE-39 countermeasure system, and its electronic support measures were improved to allow better classification of contacts by their radar and radio emissions. Lastly, it finally received the capability to utilize the AGM-84 Harpoon missile, with the pair of missiles being mounted on the outer hardpoints. With a range of approximately 75 nmi’s, the sea skimming Harpoon could prove very difficult to detect and shoot down. As more effective air defenses against sea skimming missiles would not become widespread for almost a decade, the inclusion of this weapon would make the Viking a considerable anti-surface asset, along with its already impressive anti-submarine capabilities.

The sum of these upgrades would end up seeing the modified aircraft identified as S-3B’s, as squadrons began to receive the improvements in 1984. In addition to these upgrades and after the parts shortage, the scope of duties for the aircraft began to grow over the years. Among the first new tasks assigned to the Viking was to act as an airborne tanker. The long endurance of the aircraft, coupled with its incredibly fuel efficient turbofan engines, made it extremely capable in the new role. Carrying ‘buddy stores’, the S-3 could increase the range and endurance of cooperating carrier-borne aircraft in a much more efficient manner than the Ka-6d tanker, or a fighter or strike aircraft carrying the fuel tank and drogue system.

As the 1980s drew on, the Navy began to push the operational limits of the aircraft out ever further, and to great success. The S-3 took on the aerial mining mission, and during the Northern Wedding and United Effort exercises of 1982 and 1983, the operational search range of the Viking was pushed out to 1000 nmi with the use of airborne tankers. Even more noteworthy, they were able to detect and track submarines at that range during the exercise. While the S-3 Viking was initially introduced to serve a single, and very specialized purpose, the aircraft would end up proving extremely versatile and provided a number of new services to the carrier fleet, far beyond the expectations of its designers.

Operation Desert Storm and Late Career

An S-3B tanker launches from the deck of the USS Nimitz. [National Archives]
As the Cold War came to a close, events in the Middle East soon culminated in the largest armed conflict since the end of the Vietnam war. As Iraq invaded the neighboring country of Kuwait over oil disputes, a coalition was built among Arab and Western militaries to oust Iraqi forces from Kuwait and deal a serious blow to Saddam’s forces. Along with a massive USAF contingent, the US Navy would deploy six aircraft carriers in order to dislodge the Iraqi army from Kuwait. Of the force, USS Kennedy, Saratoga, America, Ranger, and Roosevelt carried embarked squadrons of S-3B’s. USS Midway lacked a squadron of Vikings, as it did not possess an ASW analysis center.

A total of 43 Vikings would be active across these carriers by February 1991, where they would serve in a number of roles. Ironically, due to Iraq’s lack of a submarine force, ASW was not a role they performed during this conflict. These aircraft flew a total of 1,674 sorties between January 17 and February 28, 1991. The majority, with 1043 flights, were aerial refueling missions supporting other coalition aircraft. However, they also flew a number of reconnaissance, electronic warfare, and several surface air combat patrol sorties, these numbering 263, 101, and 20, respectively. The rest of their flights were categorized as unspecified support missions, or ‘other’.

Apart from aerial tanker duties, these Vikings flew most of their patrols to survey the Persian gulf, in order to track what few warships Iraq had, and to mark the location of mines. Some Vikings were also involved in the search for Iraq’s short range Scud ballistic missiles, a great fear at the time being that some of them may have carried chemical weapons payloads. They also performed a number of unorthodox tasks. For instance, the US carrier air groups could not electronically receive their daily air tasking orders from the coalition headquarters in Riyadh, Saudi Arabia. Their solution was to dispatch an S-3B to pick them up on a near daily basis. Among the most imaginative uses of the aircraft was in delivering photos from carrier based reconnaissance services to units fighting on the ground. This was done by placing the photos in an empty sonobuoy tube and parachuting them to units. One Viking also sank an unidentified class of Iraqi patrol ship on February 20, 1991, after dropping three unguided mk82 bombs on it. Offensive patrols were comparatively restricted and were conducted in areas with limited anti-aircraft threats.

A long exposure shot of deck crew preparing an S-3B on the USS Truman during Operation Desert Shield. [National Archives]
After the end of the war in the Gulf, the S-3B was used for continued surveillance of the area and to uphold the sanctions on Iraq during Operation Desert Shield. It likewise performed similar support roles in the numerous NATO air operations over the former Yugoslavia. Their roles during those conflicts were almost entirely restricted to airborne tanker duties, though a number of Vikings, including a specialized ELINT model, performed signals intelligence missions.

As a result of the collapse of the USSR, the global submarine threat to the US Navy declined to almost nothing, and thus the Viking squadrons transitioned from anti-submarine, to surface control units to better represent their more multipurpose role. They would eventually discard their ASW equipment, with the anti-submarine mission being made the purview of the US submarine fleet and long range maritime patrol squadrons. Several new upgrades were initiated during the turn of the millennium, mostly in regards to new avionics and improvements to carrier landing aids. They would also include the Maverick Plus upgrade, which would enable the S-3B to use IR guided models of the AGM 65 missile, and the AGM-84H family of ground attack missiles. However, after the KA-6D left the service in the late 90s, the Viking would become the fleet’s primary aerial tanker.

The last major operation where the Vikings saw use was during the later invasion of Iraq, during which they primarily acted as tankers. There were, however, some strikes carried out by S-3Bs using the new Maverick Plus system, but these were comparatively rare. As the 2000’s came to a close and the US carrier force wished to divest itself of all but the most essential airframes, the Viking had fully left the service by 2010. The fleet was thus without a dedicated aerial tanker, and instead employed F/A-18s carrying ‘buddy stores’ to refuel other fighters.

Perhaps its later most publicized use was in delivering President George H.W. Bush aboard the carrier USS Abraham Lincoln after the invasion of Iraq. There, he delivered an address to the nation regarding the end of Operation Iraqi Freedom, in front of the long derided banner which simply read ‘Mission Accomplished’.

NASA

While the Viking’s military career came to a close, a number of aircraft were transferred to NASA as test aircraft in 2004. One of these planes was further developed into a dedicated testing platform in 2006 and was subsequently demilitarized. Most of the existing avionics were replaced with more contemporary civilian equipment and provisions for adding experimental equipment were installed. The Viking was given the civil air registration code N601NA and would see heavy use by the administration for the next 15 years, with the remaining Vikings being used for ground testing.

The NASA Viking proved to be an ideal platform to run a variety of experiments that required steady, precise flying at low speeds. [aionline]
The plane was used for a variety of missions regarding aeronautic safety, aerodynamic studies, and Earth studies. Operating out of the Glenn research center, the plane tested engine icing under harsh conditions, flew communication equipment tests over much of the US to determine FAA guidelines for unmanned aircraft, and flew over the Great Lakes to study algal blooms. This Viking was the last airworthy example of the entire line, and was finally retired in July of 2021. NASA has since donated the plane to the San Diego Air and Space Museum.

Operating Characteristics

The high and broad wings of the Viking presented good low speed flight characteristics and high maneuverability. This was also aided by the lateral control system of the aircraft, which consisted of a set of small outboard ailerons, a pair of spoilers above the wing and one on the underside, and a leading edge flap. Pilots in both the Navy and NASA test programs praised the responsiveness and stability these systems provided. This ability was well valued during low altitude MAD searches and during low level communications testing for NASA and the FAA. However, at higher speeds, pilots needed to be aware of a degree of oversensitivity, as the aircraft did not possess a fly by wire system.

A view of a carrier flight deck from the cockpit of a Viking. [The Drive]
The Viking had an extremely high carrier boarding rating thanks to its dynamic lift system, which in combination with the spoilers, gave the pilot a high degree of control during their final approach. The slow descent of the aircraft also permitted both the pilot and the LSO considerable time to make alterations. This is not to say this was a simple affair, as the aircraft was fairly sensitive to the air disturbance that forms immediately behind the moving carrier, and thus the pilot is still required to make the approach with caution. The engines had to be practically idled on the glide slope, and still often felt overpowered. The DLC system was essential, though the flaps were not, with many recoveries being flap up. Getting off the carrier was a far easier affair, as the aircraft only had a speed requirement of 120 kts under a normal load. Off wind catapult launches were made easily and some pilot and ground crew would remark that the Viking seemed like it could just fly off on its own. In both launching and recovery, the aircraft was remarked to handle well under poor conditions.

The addition of an APU in this aircraft greatly simplified and accelerated the start up procedure, as it did not require the pilot to request external power from the deck crew. A relatively simple start up enabled the aircraft to be ready some 15 to 20 minutes before its scheduled launch, and helped in speeding up the turn-over in deck operations. The only inconvenience the aircraft presented was that its low mounted engines were considerably quieter than most other embarked aircraft, meaning ground crew needed to pay particular attention to these aircraft as they moved across the deck. In short, the S-3 was very well suited to carrier operations.

A technician checks over the TACCO’s multipurpose display on an S-3B. The displays at each station were of slightly different dimensions. The TACCO station’s monitor was enlarged on the B model of the aircraft. [National Archives]
A high level of crew cooperation was possible on the Viking thanks to the centralized nature of its avionics, sensors, and weapon systems. In managing all of these functions through its central computer, most crew functions were visible across all stations and, in some cases, could actually be managed between them. This was primarily achieved through the multipurpose displays at each station, which allowed crewmembers to share information. This made the SENSO and TACCO stations far more capable than they were on other aircraft, allowing for some division and management of the workload. The TACCO position likewise possessed a high degree of integration with the pilot and copilot, and in certain autopilot modes, could guide the aircraft to the weapon release point. All stations effectively had a high degree of situational awareness outside the aircraft, as the multipurpose displays could be set to show various airborne, surface, and subsurface contacts relative to their positions from the aircraft. The computer system itself proved fairly easy to manage, and designed with self-maintenance in mind. In the event of a system error, the computer could run a diagnostic and be reset in flight. Thanks to this level of digital integration, the Viking was viewed as being as capable as a number of patrol aircraft with significantly larger crews.

In the submarine hunting role, the Viking was in no shortage of equipment. The primary means of conducting an anti-submarine search were its sonobuoys. The aircraft carried a variety of these devices, which allowed for passive listening, or actively sending out an echolocating ping which revealed the positions of nearby submarines. These were often arrayed out in a grid like pattern in an aircraft’s patrol area to allow for the surveillance of a much larger area. They were typically dropped in line-like, or triangular patterns when used to try and get an accurate fix on the submarine’s location. Through acoustic analysis, the Viking was able classify submarine contacts by comparing them to existing sound profiles and was capable of gathering new profiles on vessels which had not yet had one compiled. Sonobuoys were usually dropped from the aircraft’s cruising altitude of 35,000 ft, though often from lower altitudes when a contact had been found and a finer pattern of the devices needed to be sown. The sonobuoy system was the first of its kind capable of accurately pinpointing the position of each device.

Sonobuoys provided a screen through which a transiting submarine could be detected, though they were not used for basic open ocean searches. The limited effective range of the individual devices meant that they were used for screening areas ahead of surface groups, filling gaps between other patrol areas, and investigating contacts that were beyond the range of other warships. The aircraft could hand off its sonobuoys to other aircraft from a shared channel, and could receive information from other, off-aircraft sensor sources through their datalink. Thus, in the submarine hunting role, the aircraft could either be a proactive tool, in performing its own searches, or reactive, in responding to suspicious or identified subsurface contacts from other aircraft and vessels. In concert with more modern anti-submarine assets, like the Spruance class destroyer or underwater hydrophone lines, the Viking could prove an incredible asset well beyond the limitations of its own sensors. The Viking was one of, if not the, best equipped ASW aircraft of the entire Cold War. Designed primarily around countering the threat of nuclear submarines, it would of course prove even more capable against diesel-electric submarines which presented more opportunities for detection.

Carrier deck crew load a sonobuoy into the aircraft’s external chutes. Viking’s could carry passive, active, dual purpose, oceanographic, and search and rescue beacon buoys. [National Archives]
In conjunction with sonobuoys, the aircraft possessed its radar, FLIR optics, and a magnetic anomaly detector. The radar of the aircraft was designed to detect periscopes and snorkels deployed by near surface submarines. The key was to look for contacts that either appeared or disappeared from the scope without explanation, and was otherwise a very straight forward system. The FLIR sensor was used to detect heat sources, and in the submarine hunting mission, was used to spot submarines at a shallow depth, and the extended snorkel and exhaust of diesel-electric submarines recharging their batteries. Last was the MAD, which detected the magnetic field of a submarine, which caused slight disruptions in measurements of the earth’s magnetic field, hence the anomaly. This was the only sensor which required the aircraft to fly low, and the limited range of the sensor also meant a contact was typically only revealed if it was overflown. The radar and infrared systems were also important tools in conducting long range surface reconnaissance for the entire fleet. These systems were also necessary in providing targeting data for the Harpoon anti-ship missile.

In employing weapons, the majority of the work was done through the TACCO position. This crewmember assigned weapons to targets, and in coordination with the pilot and copilot/COTAC, delivered them. Originally, this meant he would deploy the Mk.46 lightweight torpedoes and depth charges, with the plane being capable of deploying nuclear models as well. Unguided munitions, typically Zuni rockets, Mk 82 iron bombs, or Mk 20 Rockeye cluster bombs, were the responsibility of the pilot and would have been used against surfaced guided missile submarines, or damaged warships. Later in the aircraft’s career, the TACCO would deploy mines, launch AGM 84 Harpoons, and later operate a variety of air to ground missiles with the introduction of the Maverick Plus upgrade.

The aircraft later excelled as an airborne tanker, where its ability to operate for long periods and at range from the carrier were crucial. The task was relatively simple enough, fly straight ahead while offloading fuel onto another aircraft through a hose and basket fuel transfer line. The asymmetric load of the fuel tank and drogue mount required constant trimming, which grew worse as the tank was drained, but this was a largely simple job the plane was well suited for.

Construction

A general diagram of the S-3B. [S-3B manual]
The S-3 was a high wing, twin engine, carrier based anti-submarine aircraft. It possessed a very durable semi-monocoque airframe with three folding flight surfaces, being the wings and the vertical stabilizer. The fuselage was wide enough to permit the fitting of a considerable set of ASW gear, and an internal weapons bay. The general construction of the aircraft was fairly conventional in comparison to other carrier based aircraft. Lockheed was the primary contractor for the aircraft,  with LTV building the wings, engine pods, tail assembly, and landing gear, while Univac provided the digital computer and some of the avionics.

The nose of the aircraft contained the radar, followed by the cockpit which seated the pilot and copilot, behind them were the weapons and sensor operators. Aft of the crew sat the forward avionics bay, which itself was over the internal weapons bay, and to the rear of it all was the MAD boom and rear avionics bay. On the underside of the aircraft were the sonobuoy shoots, which in addition to the 48 outer slots, held additional internal stores for 12 more devices. All critical systems had redundancy built in.

The landing gear, and catapult launch bar, were derived from those of the LTV F-8 Crusader and A-7 Crusader II. These consisted of a forward, upward retracting gear and two rear landing gear which retracted inward toward the fuselage. These are hydraulically actuated, though in an emergency, they could be extended by bypassing the hydraulics and letting gravity, and a leaf spring to force the gears into the extended position.

The wings of the aircraft were designed to permit a high degree of control and stability at both low and high speeds at low engine power, up to the maximum permitted speed of 429 kts. These were mounted high on the fuselage and possessed a high aspect ratio of 7.73 and a rearward sweep of 15 degrees. The wings consisted of an outer panel, which could fold inward, and an inner panel, roughly a third the length of the outer panel, which contained a fuel tank, and supported an engine nacelle and a pylon which could fit external fuel or weapons. The tall vertical stabilizer also folded down and to the port side to permit the aircraft to fit the carrier’s hangar doors. The extendable airborne refuel probe was stored just ahead of the wings.

Spoiler, aileron, and flap deployment diagram. [S-3B Manual]
The Viking possessed an unusual flight control system which combined six large spoilers with a set of small ailerons and a leading edge flap. Lateral control was greatly aided by the inclusion of the spoilers in combination with the leading edge flap, which permitted effective control at very low speeds with low engine power settings. All control surfaces on the aircraft were deflected using hydraulically actuated servos, with an artificial feel system designed to give the pilot an idea of the extent of control surface deflection. These controls did however prove to be somewhat oversensitive at high speed. Overall, the control surfaces were very effective on patrols at low speed, though they could prove rather clumsy in a carrier landing pattern. This was largely due to the overpowered engines, which gave the aircraft a somewhat unorthodox glide slope and its large wings increased its sensitivity to the ‘burble’ air disruption behind the carrier. To compensate for this, the Viking was equipped with a dynamic lift control system which provided 12 degrees of speed brake extension and retraction through the upper spoilers.

The S-3 was powered by a pair of either General Electric T34-GE-2 or T34-GE-400A high bypass turbofan engines. These both produced 9,275 pounds of thrust at sea level, and the former was used only on pre-production aircraft. These engines used a dual-rotor, single stage, front-fan configuration with a bypass ratio of 6.23 to 1. These were divided into four major sections, being the fan, compressor, combustor, and turbine. The fan was driven by the low pressure turbine and produced 85 percent of the engine’s total thrust. The compressor was composed of 14 stages which compressed air prior to the combustion section, and provided the air for the pneumatic systems aboard the aircraft. The combustor section was where the compressed air was mixed with a fuel air mixture and ignited. The resultant flow drove the high and low pressure turbines within their own section, the high pressure turbine being responsible for driving the compressor, and the low, the fan. The air flow continues out the back of the low-pressure turbine to comprise the remainder of the engine’s thrust.

Standard and exploded views of the General Electric T34-GE-400A turbo fan engine. [S-3B Manual]
The aircraft was fitted with a number of surface and subsurface sensors. The Viking originally possessed an AN/APS-116 search radar, which was primarily designed to detect the masts of submarines near the surface, but doubled as a general purpose surface search radar. This was replaced on the S-3B with the APS-137 inverse synthetic aperture radar which was more than twice as effective at detecting low RCS masts and had improved surface search capability. Specifically, it gained the ability to identify surface vessels at long range by comparing radar returns to existing 2D profiles of vessels. The aircraft also carried an AN/ASQ-81 magnetic anomaly detector fitted to an extendable boom at the rear of the aircraft often called the ‘Stinger’. The boom allowed the sensor to be placed farther away from ferrous objects on the aircraft, which might interfere with any measurements taken. They also carried the OR-89 FLIR sensor, it being mounted in an extendable turret on the forward, starboard side of the aircraft. The sensor would display surface and near surface contacts, making it extremely useful in detecting mines, submarines at a shallow depth, and the exhaust of diesel-electric submarines charging their batteries.

The Viking’s FLIR turret in its deployed position. [replane]
What could be considered the primary anti-submarine sensor were the aircraft’s sonobuoys. Up to 60 could be carried in the chutes that sat flush with the outside of the aircraft and internal stowage. The aircraft communicated with minimal signal emissions and was capable of displaying their exact positions. Data from the devices was processed using an OL-82/AYS data processor and, coupled with its original receiver, was initially capable of monitoring 31 buoys. When upgraded, the acoustic data processor incorporated a new standardized UYS-1 signal process which had improved reliability and had parts and software commonality with other ASW platforms. A more advanced sonobuoy reference system, AN/ARS-2, would also boost the number of usable sonobuoy channels from 31 to 99 and an automatic channel scanning capability to search for available RF channels. The last upgrade to this system saw the analogue tape recorder switched from AN/ASH-27 to the AQH-4(V)2, which was both smaller, more reliable, and was compatible with the new UYS-1 signal processor.

The rear two stations of the S-3A Viking. The SENSO’s dual screens allowed him to monitor multiple sonobuoys simultaneously, this information being only partially available to the single screen displays at all of the other positions. [S-3B Manual]
The aircraft’s countermeasures initially came in the form of the AN/ALR-47, a passive sensor which displayed radar emissions from search and track radars. This was later supplemented with the ALE-39, which included countermeasure dispensers. It also received electronic support measures, which allowed it to detect a wider variety of radar emissions to allow it to classify their emitters. In the event of being shot down, the aircraft was equipped with ejection seats. These could be used on the ground while the aircraft was still, and had a preset ejection sequence to prevent any collisions in air.

All of these systems were managed through a single Univac AN/AYK-10 digital computer. The system allowed for a much higher ability to process information compared to the isolated systems in use on virtually all other maritime patrol craft. Additionally, and perhaps much more importantly, it allowed the crewmembers to display information from their own stations to one another through a set of multipurpose display screens at every station. This allowed for the sharing of most sensor data across all four positions, though it was more limited in the case of sonobuoy readouts, as they were half displayed on a secondary screen at the SENSO station. These displays would give crews the ability to coordinate during surface and subsurface searches, and improve planning when preparing to attack. This was particularly valuable to the copilot/COTAC, whose job was to essentially direct the aircraft in achieving its mission. The addition of this system essentially gave them access to every senor and allowed them to work closer with the TACCO when it came time to deploy weapons.

Initially, the Viking could be armed with up to four Mk 46 torpedoes, being either the Mod 1 or Mod 5 NEARTIP during the 1980s. Both types measured 8.5 ft long with a diameter of 12.75 inches, and both carried a 95 lb warhead. The Mod 1 possessed a maximum speed of 45 kts,with the NEARTIP being considerably faster. The NEARTIP provided better tracking of faster targets and better countermeasure rejection, having incorporated a new sonar transducer, control and guidance group, and a new engine which switched from solid propellant to liquid monopropellant. The Viking would also receive the new electric Mk 50 torpedo in the early nineties, but it would shortly after transition away from the ASW mission. There were provisions for mounting up to four torpedoes internally from hardpoints rated up to 600 lbs each. The bomb bay could also carry up to four mines and depth charges, or two B57 nuclear depth charges.

Crewmen prepare to load a Mk 46 torpedo aboard an S-3A. [National Archives]
The pair of external hard points could carry a combination of weapons, external fuel tanks, and airborne refueling systems. Initially, this was restricted only to unguided weapons and fuel tanks. Each hardpoint had a mounting capacity of 2,500 lbs and could carry up to three bombs through the use of the TER-7 bomb mount. The S-3B upgrade would allow the aircraft to use the AGM 84 Harpoon and was able to carry two of these sea skimming missiles. The last major upgrade package, which was installed around 2002, included a variety of avionics improvements, and the Maverick Plus system. This allowed the Viking to mount the AGM 65 Maverick, one per hardpoint, and the AGM-84E SLAM. The Maverick was to be used mostly against light shipping, with the SLAM providing stand off capability against ground targets. The SLAM could be guided manually after launch if a guidance pod was installed on one of the outer hardpoints. Both missiles were otherwise supported and targeted through a common display.

The S-3B could use any of the AGM-84’s in the Navy’s arsenal by the time of its introduction. The first of these was the Block 1B introduced in 1982, which had improved radar guidance allowing it to fly at lower altitudes. The subsequent 1C entered service in 1984 and incorporated a denser fuel, which increased its range by five nautical miles out to 80 nmi when launched from sea level, and added an alternate pop-up attack mode. The 1D entered service in 1992, with the lengthened missile possessing a range of 150 nmi and re-engagement capability, which allowed the missile to circle back to its target if it was deceived by chaff or electronic countermeasures on its first pass.

These sea skimming, turbojet powered missiles were exceptionally difficult to detect and intercept during the Cold War and flew at a constant Mach .85. These utilized active radar terminal homing, carried a 510 lb high explosive warhead, and had a flight reliability of over 93 percent.

Conclusion

A Viking prepares to launch after an F-14B Tomcat aboard the USS Nimitz during Operation Southern Watch, 1999. [National Archives]
With the exception of the parts shortage, the Viking can be said to be among the most reliable and versatile tools the US Navy has ever possessed. The aircraft proved a phenomenally capable anti-submarine aircraft, which entered service long before high capability threats entered service in the Soviet Navy. When that particular threat had gone, the plane continued to serve ably, as a tanker, a reconnaissance aircraft, and limited strike aircraft. Finally, the venerable aircraft ended its career as a research aircraft.

S-3A Viking

Specification

Engine T34-GE-400A
Maximum Continuous Engine Output (Maximum) 6,690 lbs (7,365 lbs for 5 minutes)
Combat weight at catapult 44,947 lbs
Gross Weight 36,574 lbs
Empty weight 26,581 lbs
Range [4x Mk.46 60xSonobuoys] 2,506 nmi
Combat radius [4x Mk.46 60xSonobuoys] 826 nmi for 6.9 hours at 346 kts
Maximum speed 429 kts at sea level
Crew Pilot, Copilot/COTAC, TACCO, SENSO
Length (Folded) 53.33 ft (49.42 ft)
Height (Folded) 22.75 ft (15.25 ft)
Wingspan (Folded) 68.67 ft (29.50 ft)
Wing Area 598 sq.ft

S-3 variant

General Description

Number built/converted

YS-3A Prototype/Preproduction 8 built
S-3A ASW Aircraft 180 built
S-3B ASW/ASuW Aircraft 160 converted from S-3A
US-3A Cargo Aircraft 4 converted from YS-3A
KS-3A Airborne Tanker 1 converted from YS-3A
ES-3A ELINT Aircraft 16 converted from S-3A

Viking Squadrons

VS-21 ‘Fighting Redtails’ VS-31 ‘Topcats’
VS-22 ‘Checkmates’ VS-32 ‘Maulers’
VS-24 ‘Scouts’ VS-33 ‘Screwbirds’  
VS-27 ‘Grim Watchdogs’ VS-35 ‘Blue Wolves’
VS-28 ‘Gamblers’ VS-37 ‘Sawbucks’
VS-29 ‘Dragonfires’ VS-38 ‘Red Griffins’
VS-30 ‘Diamondcutters’ VS-41 ‘Shamrocks’

(wikimedia, popular patch)

Credits

  • Article written by Henry H.
  • Edited by  Henry H. and Stan L.
  • Ported by Henry H.
  • Illustrated by Hansclaw

Illustrations

Gallery

The Viking flying alongside the older S-2 Tracker maritime patrol aircraft. The S-3A rapidly replaced the Tracker from 1974 to 78, when the last Viking left the production line. [jrdavis]
An S-3 is brought up to the flight deck in its stowed condition. The vertical stabilizer folds just below the rudder. [National Archives]
A member of the USS Enterprise’s deck crew warms their hands in a turbine. Taken during the Fleet EX’88 Exercise off the coast of Alaska. [National Archives]
A Viking prepares to launch from USS America. [National Archives]
The evaluation S-3B aircraft passed its final trials in 1985. A rapid upgrade program would begin in 1987. [flight manuals online].
S-3Bs on the crowded deck of the USS John C. Stennis in 2007. [National Archives]
An SH-60 Seahawk comes in to land on the USS Kitty Hawk. [National Archives]
A Sikorsky Sea King comes in to land on the USS Theodore Roosevelt. These helicopters and the Sh-60’s represented the inner circle of fleet anti-submarine defense. [National Archive]
 

A Viking, among other aircraft, aboard the USS John F. Kennedy. [National Archives]

An aircraft prepares to take on fuel from an S-3B tanker. Note the missing MAD boom and the covered sonobuoy chutes. [National Archives]
The most publicized use of the Viking. ‘Navy One’ lands on the USS Abraham Lincoln with President George W. Bush aboard to deliver a less than well received speech after the end of Operation Iraqi Freedom. [US Navy]
The ES-3 Shadow was an electronic surveillance aircraft which replaced the aging Skywarrior. It saw considerable use during the NATO intervention in the former Yugoslavia, where it monitored communications and radar emissions. It is easily distinguished by its dorsal equipment fairing [FAS]
A Viking with its MAD ‘stinger’ deployed. [The Drive]

Sources

Primary

Standard Aircraft Characteristics Navy Model S-3A Aircraft. Commander of the Naval Air Systems Command. NAVAIR 00-110AS3-1. January 1973.

NATOPS Flight Manual Navy Model S-3B Aircraft. Commander of the Naval Air Systems Command. NAVAIR 01-S3AAB-1. September 2000.

NATOPS Weapon System Manual Navy Model S-3B Aircraft. Commander of the Naval Air Systems Command. NAVAIR 01-S3AAB-1.1. December 2002.

Fiscal year 1976 and July-September 1976 transition period authorization for military procurement, research and development, and active duty, selected reserve, and civilian personnel strengths : hearing before the Committee on Armed Services, United States Senate, Ninety-fourth Congress, first session, on S. 920

NASA fiscal year 2010 budget request : hearing before the Subcommittee on Science and Space of the Committee on Commerce, Science, and Transportation, United States Senate, One Hundred Eleventh Congress, first session, May 21, 2009.

Department of Defense authorization for appropriations for fiscal year 1982 : hearings before the Committee on Armed Services, United States Senate, Ninety-seventh Congress, first session, on S. 815.

Department of Defense appropriations for 1984 hearings before a subcommittee of the Committee on Appropriations, House of Representatives, Ninety-eighth Congress, first session / Subcommittee on the Department of Defense.

NASA’s aeronautics R & D program : status and issues : hearing before the Subcommittee on Space and Aeronautics, Committee on Science and Technology, House of Representatives, One Hundred Tenth Congress, second session, May 1, 2008.

Department of Defense authorization for appropriations for fiscal years 1988 and 1989 : hearings before the Committee on Armed Services, United States Senate, One hundredth Congress, first session on S. 1174.

Department of Defense appropriations for 1985 hearings before a subcommittee of the Committee on Appropriations, House of Representatives, Ninety-eighth Congress, second session / Subcommittee on the Department of Defense.

Department of Defense authorization for appropriations for fiscal year 1983 : hearings before the Committee on Armed Services, United States Senate, Ninety-seventh Congress, second session, on S. 2248.

Secondary

Chambers, Joseph R.. Partners in freedom: contributions of the Langley Research Center to U.S. military aircraft of the 1990’s.

Brown, Ronald J. Humanitarian operations in northern Iraq, 1991: with marines in Operation Provide Comfort.

Knaak, Jerry. A Hunting We Will Go. Naval Aviation News. March-April 1997.

Vikings Sweep the Seas & Viking. Naval Aviation News February 1983.

LSO School and the Paddles’s Profession. Naval Aviation News V70, November-December.

Benjamin, Dick. A Sea Rover for ASW. Naval Aviation News January 1972.

Richman, John P. The Viking at Home in the Fleet. Approach, July 1975.

Francillon, Rene J. Lockheed Aircraft Since 1913. Naval Institute Press. 1987.

Polmar, Norman & Moore, Kenneth J. Cold war Submarines The Design and Construction of U.S. and Soviet Submarines. Potomac Books. 2004.

Polmar, Norman. Aircraft Carriers a History of Carrier Aviation and its Influence on World Events Volume II 1946-2005. Potomac Books. 2007.

DELAG: The First Airline

German Empire, German Republic, Nazi Germany

9 Airliners

The airliner Hansa prepares to depart from Potsdam. (stampcircuit)

Intro:

While the age of the airship has long since passed, these aircraft were involved in a nearly 30 year battle for aerial supremacy with the airplane. This competition would lay the foundations for modern air travel and, as the railway once did, change humanity’s conceptions of space. The Zeppelins of the DELAG airline earned the honor of being the first aircraft to regularly fly passengers, and to be the first to offer transatlantic air service from Europe to the Americas. While the destruction of the Hindenburg, operated by the DZR, spelled the end for passenger airship travel, DELAG’s airships had defined modern air travel with a near spotless safety record.

The Count

Count Ferdinand von Zeppelin was born in the Grand Duchy of Baden in 1838 as the second of three brothers to a fairly unremarkable aristocratic family. His father was an aristocratic native of the region and his mother being of French-Swiss descent. As a child, Ferdinand was educated by a tutor hired by his family before joining the Army at age 15 in 1858. He saw no action in the Franco-Austrian war in 1859, and in the peace before the Kingdom was embroiled in the wars of German unification, Zeppelin would continue his education. He took courses at the Stuttgart Polytechnic institute, the University of Tubingen, and the Royal War College. Zeppelin was an odd character, traditional, curious, fascinated with machines, and equal parts ambitious and stubborn.

He was far more adept in terms of his technical knowledge than other aristocrats, with engineering typically being reserved for young men of the middle class. Zeppelin, however, could not be considered a true engineer owing to the broadness of his studies. His formal education would end in 1861 when he began to travel Europe at the behest of the Army, observing the armies of foreign nations. He would travel to Austria, Italy, and France before finally making his way to the Americas, then embroiled in civil war.

Count Zeppelin during his time with the Union Army, pictured center. (wikiwand)

This journey, however, was a personal venture, the young Lieutenant Zeppelin having taken leave to see the conflict. He would arrive in Washington DC in 1863 where he acquired permission to travel with the Union Army after a meeting with President Lincoln. Zeppelin soon found himself in the headquarters of the Army of the Potomac in May, and was disappointed soon after. In short, apart from an impromptu escape from a Confederate cavalry patrol in Ashley Gap, Virginia, his experiences with the Union army were dull and uninformative. He felt that their ways of fighting were clumsy and dated, and that the openness and frankness of officers with their superiors was unprofessional and unwarranted. It seemed the entirety of the trip seemed a loss, militarily he found no new lessons or methods to be found with the Army of the Potomac. This was until he encountered Professor John Steiner, an aeronaut who formerly flew as a balloon observer in the service of the Union army.

By this time, the balloon had become a valuable, though uncommon, tool of the Union army, and a ride for thrill seekers. Steiner flew his balloon the ‘Hercules’ for the public after serving with the Union’s balloon corps. The Bavarian born aeronaut met Zeppelin in Saint Louis during the former’s diversion to see the Great Lakes. The two had very little in common apart from their first language and an interest in technology, which quickly sparked a long conversation over balloons and their operation. They spoke of the difficulties and limitations of the existing spherical balloon, which had to be tethered, lest it be carried off by the wind, and was almost impossible to keep them oriented in anything but the most mild weather.

With the end of their conversation, Zeppelin was eager to set off in the balloon. So eager in fact, that he purchased much of Saint Louis’ supply of coal gas to ensure his fight, to the annoyance of its residents. The two took to the sky on August 19, 1863, rising to around 55 meters. In the air, Zeppelin was not amazed or awestruck by the feeling of flight, in fact he never would be, but he saw in it both an immense promise and a series of problems to be solved. To the aerial observer, every detail of the landscape was revealed, and to a military man like Zeppelin, its value was evident and extraordinary. However, it wasn’t without its drawbacks. To his frustration, the balloon had to remain tethered, as uncertain winds could take the balloon any number of directions and Steiner didn’t believe they had enough coal gas for a long flight. The two would part ways after the flight; Steiner would later design and build his own portable hydrogen generator, and Zeppelin would return to Württemberg to resume his service with the army.

Zeppelin wouldn’t fly again for forty years and by the time he had returned home, he had largely thought the issues surrounding balloon flight were yet unsolvable. The Lieutenant would return to his homeland facing the Prussians, who were then seeking to establish their hegemony over their neighbors in a new central German state. Zeppelin was promoted to Captain and an aide-de-camp to the King in 1866. He would see no action, and witnessed the loss of the Austrian led coalition. Zeppelin remained in the army after the loss and was later married to baroness Isabella von Wolff.

With the start of the Franco-Prussian war, Captain Zeppelin was once again called into service, and with some good fortune, placed back on the path to aeronautics. Zeppelin would see action in this war, in the form of a daring, if brutal cavalry mission which saw everyone in his unit except him, killed or captured. He was subsequently honored by his homeland of Württemberg, and met with a decidedly cold reception by the Prussians, with whom he had developed a growing antipathy towards. However, Zeppelin’s key moment of the war came at the outskirts of Paris.

The Neptune was the first balloon to fly out of Paris, photographed here on 23 September 1870. (wikimedia)

When the war had been decidedly lost for the French, the capital remained a brave, but doomed, holdout. As Zeppelin waited on the outskirts of the city with the rest of the Prussian-led coalition, he noted the many balloons that departed the city. Numerous French aeronauts made flights out of the city, carrying news and letters out with them. Zeppelin once again saw the drawbacks of the balloons, the wind drew them in random directions, though most landed in friendly territory. He would still regard the balloon as questionable at best, and though he would take note of their ability to drift over the blockade safely, he lamented that they were totally unnavigable.

After the war Zeppelin remained with the army, being given command of the 15th Schleswig-Holstein Uhlans. For many years, he expected that this would be the end to the most exciting chapters of his life and prepared himself for a relaxing, if uneventful retirement. In all likelihood this would have happened, had it not been for a riding accident on March 18, 1874 (Robinson 9-13, Rose 3-12).

The Dream

After a particularly violent fall from his horse, Zeppelin was placed on several weeks of sick leave. During his recovery a fellow staff officer had come to deliver his well wishes, and some reading material, which included a pamphlet from the head of the new Imperial Post Office entitled World Postal Services and Airship Travel. The pamphlet, and a subsequent lecture Zeppelin attended, would set his imagination running. Soon he would begin accumulating basic airship concepts, though these early ideas proved very crude. Such was the case for a large airship which controlled its altitude solely through dynamic lift, and no ballast. However, from this early point he would also conceptualize the use of a rigid hull formed from rings and longitudinal beams which would contain a number of individual gas cells. Several features, like propulsion, were simply omitted as they had not yet been developed. It is curious that Zeppelin conceived of his first vessels without a way to move them, but in a period of such rapid technological development as the late 19th century, it was not an unreasonable assumption that the problem would be solved soon enough (Robinson 14). In Zeppelin’s case, the ‘suitable prime mover’ that his first concept used, materialized in less than a decade when Daimler produced the first series of reliable gasoline internal combustion engines.

Perhaps most crucially of all, Zeppelin understood the airship would operate as a series of independent components which could be developed, and improved upon separately. Its hull structure, gas cells, control systems, and propulsion could and would be developed in turn.

These developments, however, would be stalled for some years following the birth of his daughter, Hella, and his return to military service. This hiatus would only end with the end of the Count’s military career. By this time, the German Empire had only existed for some few years, and its second sovereign, Wilhelm II, was defined mostly by his insecurities and petulence. His greatest irritation were those in the Empire who still held to their regional identities and allegiances to their local Kingdoms and Duchies, over the Prussian dominated Empire. In this way Zeppelin found himself labeled a ‘peculiarist’ by the Emperor after he submitted a report in which he wished that the Army of Wurttemberg would retain a degree of autonomy and that its King not simply become a rubber stamp for the governing of the Empire. These sentiments instantly made him an enemy of the Emperor, and despite a glowing review from General Von Heuduck after the Imperial War Games of 1890, he was dressed down by the Prussian General Von Kleist in front of his fellow officers (Rose 19). At fifty two, his career was over and in its place was a desire to restore his name and all the time he needed to pursue what he’d set aside years ago, building airships.

Following his forced retirement, Zeppelin soon confined himself to private study on pursuing the airship. However, beyond his desire for restoring his name, he also worked against what he saw was the newest and greatest threat to Germany, French airships. Having previously written to the king of Wurttemberg over the success of the airship La France in 1887, he was now focused on designing an aerial warship to combat it. With his declaration of ‘help me build the airship for Germany’s defense and security!’ he established his own airship development firm in 1891 (Robinson 15).

La France was an impressive airship of its day, and inspired a panic in certain military circles. (wikimedia)

Zeppelin’s firm rapidly sent out requests for engineers, manufacturers, and workers to begin his work. Additionally, he also began a correspondence with General Alfred von Schlieffen, who directed him to the Prussian Aeronautic Battalion, the best hope for getting military interest in the airship. Zeppelin’s contact with Capt. Rudolf von Tschudi of the PAB was cordial, but to found he would need to provide an approved design before funding would be forthcoming for the project (Robinson 15). Zeppelin’s first major design was led by Theodore Kober, a twenty-four year old engineer formerly employed by the Riedinger balloon factory. It was almost entirely unworkable, with the two being far too inexperienced to carry out the project successfully. The airship was designed with a layout akin to a train, with a locomotive section at its front, being 117 m in diameter, 5.5 m in length, and with a volume of 9514 cubic meters. When the design was reviewed on March 10, 1894, Cpt. Hans Gross and Maj. Stephan von Neiber of the PAB, and Muller-Breslau of the technical college at Charlottenburg, would point out the design was unworkable for countless reasons. Zeppelin refused to accept the verdict and railed against his critics, only abating when Muller-Breslau agreed to consult with him on improving the design. The resultant airship presented a length of 134 m with a 13 m diameter, its hull was cigar shaped, and its hemispherical ends were replaced with tapering ones. Despite being at first very grateful for Muller-Breslau’s much needed assistance, Zeppelin never openly credited him for his work. Zeppelin would prove a difficult man to work with, and for Breslau, this was likely a better outcome as the count often took criticism very personally and rarely, if ever, forgave a slight. Zeppelin would harbor an intense and abiding hatred in the aforementioned Capt., later major, Hans Gross, who among other things, openly supported an unsubstantiated rumor that Zeppelin had appropriated the work of the then deceased aviator, David Schwartz. A duel between the two men was only stopped by the Emperor’s intervention (Robinson 22 Rose 50).

With the shape of the airship decided, what lay ahead were the no less important practical duties of building the firm’s manufacturing base, and finances. In short, Zeppelin’s airship was to be paid for mostly by his own fundraising efforts, with his joint stock company being established in 1898, to which he paid 300,000 of the 800,000 raised. The airship’s engines were among the first major steps forward for the program, with the Count having been in contact with the up and coming Wilhelm Maybach of DMG. The correspondence between the two would result in Zeppelin’s access to the new Phoenix engine, a two cylinder engine which included a spray-nozzle carburetor and a camshaft for controlling the exhaust valves. The lightweight engine was among the most advanced internal combustion engines in the world at the time, and by 1900 it would produce 16 horsepower. The engine however, was not so much as chosen for the project, as to boost the confidence in the effort overall, as the final design would use a different model. The design team was also shaken up with Kober’s departure after the airship’s redesign, Zeppelin was fond of the optimistic young engineer, but recognized that his inexperience made it impossible to head the project. In his place came Ludwig Dürr, a solitary, humorless, 22 year old engineer. Dürr was initially derided for his eccentricities, but his talents soon revealed themselves and he outshone everyone at the firm. Such were his abilities that he became the only employee to openly disagree with Zeppelin (Rose 54). In this first project however, his tasks were focused on the fabrication and construction of the airship, most of which had already been designed when he arrived at the firm.

Possessing the best power plants available, a workable design proposal, and a very capable engineer to head the project, Zeppelin prepared to begin the work itself. The site of construction and testing was to be Manzell, Baden-Württemberg, which sat on the Bodensee, a serene lake whose shores were spread between Austria, Germany, and Switzerland. The final construction and housing of the airship was to be done within a floating hangar on the lake. Zeppelin believed water landings were much safer, and the hangar, which was to be anchored at only one end, would be able to turn with the wind, which was a considerable safety feature. At the time, the hangar was the largest wooden building in the world, which amusingly enough, was secured only by a chain which anchored it to a 41 ton concrete slab at the bottom of the lake. Construction began on June 17, 1898 with components arriving from across Germany. The airship’s aluminum frame was supplied by the Berg factory in Ludenscheid, its gas cells came from the August Riedinger balloon factory in Augsburg, the engines were shipped in from the Daimler works at Carnstatt, its gas storage tanks came from the Rhine Metal works, and its hydrogen came from the Griesheim-Elektron chemical company from the city which was its namesake (Robinson 23, Rose 54).

Humble Beginnings

Zeppelin’s airships were first assembled ashore before being delivered and reassembled in the floating hangar. (wikimedia)

The construction of Luftschiff Zeppelin 1 was an arduous task which took almost two years. Zeppelin himself was involved in ensuring nearly every part of the vessel matched its specifications and that the components he was shipped were of acceptable quality. Safety was a top priority, one that kept the 62 year old count at the firm ten hours a day for nearly the entire duration of the construction process. When completed, the airship measured 128 m and 11.7 m in diameter, its hull was composed of 24 longitudinal beams connecting 16 rings, each composed of 24 beams which were bolted together and supported by bracing cables. This hull framework was made of aluminum, which easily made it the most expensive component, as the mass production of aluminum was not yet economical. Its lift and altitude control was achieved by means of 17 cylindrical hydrogen cells with a combined volume of 11298 cubic meters, in combination with water ballast. To propel it, the airship carried a pair of Daimler 4 cylinder gasoline engines which each produced 14.2 horsepower, and were connected to two pairs of two bladed propellers through a set of bevel gears and shafts. These engines were carried in a pair of aluminum control cars in which the crew sat, with the forward car equipped with controls for the gas cells and the airship’s few control surfaces.

Controlling the airship was done through two pairs of small rudders, placed fore and aft along the sides of the airship. To control its pitch, there was a weight placed along the narrow walkway between the control cars, which was manually winched between the two to achieve the desired pitch. Climbing was achieved entirely through dumping ballast and some small degree of dynamic lift as the airship was being propelled forward (Robinson 24, Curtis).

“It was an exciting moment. When the first command to let go the cable sounded from the raft, and the airship, which, up until then, had been held by the hands of the firemen, laborers, and soldiers, rose slowly into the air, and suddenly, at the height of 25 meters was released and soared upward” -Captain-Lieutenant D. Von Bethge, steamship inspector. (Curtis 9) (wikimedia)

The long awaited flight was primed for July, 1900, with the airship being floated at the end of June. Given that only a handful of aviators worldwide had any experience in controlled flight, Zeppelin himself would take the controls. When conditions were prime on July 2nd, the airship was withdrawn from its hangar before the waiting shoreline crowd and a number of onlookers who had arrived in their boats. Along with the more casual onlookers was the head of the PAB, Bart von Sigsfeld. Before all of them, Zeppelin took off his hat and led the crowd in a short prayer before he took a boat to the airship.

Zeppelin was joined in the front car by one of his company’s own mechanics, Eisele, and a personal friend and physicist, Baron Maximillian von Bassus. The rear car would seat the journalist and world traveler Eugene Wolff along with Gross, a Zeppelin company mechanic. The airship was untethered at around 8 in the morning where it was soon trimmed to level flight. The entire flight lasted some 18 minutes, and was cut short by the trimming weight becoming jammed, and the failure of an engine, though neither proved dangerous as level trim could be maintained by venting hydrogen, and the second engine provided enough power for the remainder of the flight. From the floating hangar, the airship traveled to Immenstaad under favorable conditions, with the entire flight spanning around 5 and a half kilometers. Even with these impediments, Zeppelin was able to bring the ship in gently on the surface of the lake before returning to its hangar.

While the crowds were thrilled by the exhibition, the PAB’s response was mixed. While Sigsfeld was thrilled by the demonstration, the other two representatives had understood that while the airship was safe and capable of navigation, its low speed, reportedly between 13-26 kilometers per hour by journalist Hugo Eckener, left it unable to travel in anything by the most placid weather (Robinson 26, Eckener 1). Perhaps of greater concern was the structural damage the airship had sustained during its flight.

The aluminum beams which comprised LZ 1’s hull had warped during its flight, and likely made worse when the wind had pushed the airship ashore after it landed. Unfortunately, the girders had been laid in a manner similar to the first airship concept, and provided little strength against torsional forces and seemed unable to adequately support the weight of the motor-carrying control cars. The airship’s hull was bent upwards at both ends, and was clearly operating on borrowed time. It was reinforced and sent airborne again on September 24, where it flew for an hour and a half, and again for one last time on October 17, where it reached a top speed of 27.3 kilometers an hour and maneuvered well against the wind. These flights, however, failed to convince the military that LZ 1 was much more than a clumsy experiment.

Unable to sell the airship to the army, or even fly his prototype again, Zeppelin dismantled the company, sold its assets, and laid off his staff, save for a handful of specialists. However, to the stubborn Count, this represented a short hurdle to be overcome, and soon he would begin new appeals for funds and resources while the diligent Ludwig Dürr began to design the next airship (Robinson 28).

LZ-2

Even with its limited test flights, LZ 1 had much to teach Zeppelin’s firm on airship construction. Dürr would revise its hull, using triangular section girders that could resist warping in all planes, and they would be built with a zinc-copper-aluminum alloy, instead of soft aluminum. He also reduced the number of sides to each ring section and shortened the overall length of the airship. LZ 2 would be far simpler, and stronger than the first design.

The flimsy and unreliable lead trim weight would also be removed, with pitch control being achieved by added elevators. The small rudders of the first design were also improved, using several parallel sets in a ‘venetian blind arrangement’. Its engines too were massively improved, with Zeppelin having access to Daimler’s new 85 hp motors, which now drove three bladed propellers. Redesigning the airship would prove a surprisingly straightforward process, with each component, the hull, the motors, and the control systems being addressed and improved upon in turn (Robinson 28, 29; Rose 73, 74).

What would not prove as straightforward, was fundraising. While the first airship found a number of financiers, few shared Zeppelin’s stubborn optimism in working toward his second aircraft. The previously reliable Union of German Engineers had become outright hostile towards the Count after the LZ 1 failed to find buyers, and the public was mostly indifferent to the project. The private appeals, which bore a good deal of capital for the first airship began to fail too, bringing in only 8000 marks.

However, the Count would end up finding the money he needed. His prime supporter, King Wilhelm of Wurttemberg, once again came through and authorized a state lottery which brought in 124,000 marks. Surprisingly enough, the Emperor too gave support to the project, after the Kingdom of Prussia initially denied Zeppelin a lottery. He subsequently provided an additional 50,000 marks and instructed the War Ministry to rent hydrogen storage equipment to Zeppelin at low cost. Much in character for WiIlhelm II, his support came not from any generosity or personal interest in the Count, but out of a desire not to be outdone, and thus be under threat, from the new French Lebaudy airships.

The French airship program continued to worry and motivate Zeppelin, here, the LeBaudy brother’s airship, Le Jaune, glides by the Eiffel Tower in 1903. (air and space mag)

 

The remainder of the sum, amounting to about 400,000 marks, was acquired through a mortgage of his family’s properties in Livonia. Along with material assistance from some of his past clients, principally Daimler and Berg, the airship would be built. In all, funding the airship would prove a far greater challenge than designing and building it. While the design work began after LZ 1’s dismantling in 1900, construction would not begin until 1905 (Robinson 29, 30 ; Rose 75).

Zeppelin’s firm began building LZ-2 in April, 1905 at the same wooden shed that housed the first, though it had since been brought to the shoreline. It would be completed in seven months, though a towing accident would see its nose dip into the water, which resulted in damage that wouldn’t see it fly until the beginning of next year. It would seem rather peculiar that Zeppelin would launch the airship during the windiest, and thus most dangerous time of year, but his hand had been forced by world events. The Russian Empire, where his mortgaged estates were located, was crumbling, and the properties held as collateral were destroyed during the 1905 revolution. Zeppelin needed results, and so he raced to launch his airship.

LZ 2 presented a series of major improvements to  all of the former airship’s major components. (Wikimedia)

LZ 2 first took flight on January 17, 1906, with the Count once again at the controls, and accompanied by experienced balloonist Hauptman von Krogh, along with five mechanics. Wolff was prohibited from attending after criticizing the performance of the first airship. The flight was conducted extremely early in the morning, and with so little notice, one engineer, Hans Gassau, arrived wearing his slippers. While the weather was permissible, the flight got off to a rough start, as the crew dropped too much ballast water and the airship rose to some 450 m. After some ballast work, the crew achieved equilibrium and leveled off allowing the flight to begin in earnest. Almost immediately the airship demonstrated massive improvements as to its speed and controllability, with the craft reaching an estimated 40 kilometers an hour and demonstrating the ability to navigate in stiff winds.

However, in the midst of this promising flight, a serious problem arose. The airship proved longitudinally unstable, with its nose pitching up and down as it traveled at speed. This motion flooded the Daimler engines, stalling them, and to make matters even worse, the rudders jammed when resisting a harsh crosswind. LZ 2 was soon adrift over the lake, and it would be several agonizing minutes before they were overland and the airship’s drag anchor could be used. As the airship cleared the shore and drifted towards the Allgau mountain range, Zeppelin ordered the anchor dropped. The anchor found purchase in the frozen earth and the momentum of the ship drove it downwards as it resisted the anchor’s hold, bouncing against the ground and slowing it as it passed two local farms. Eventually it halted over nearby marshland, sustaining considerable damage from the ordeal. The crew dismounted the ship, tethered it at both ends, and left to return in the morning. Upon their arrival the following day, they found the ship had been torn to shreds in the night during a windstorm. Being tethered at both ends, the ship remained fixed and unable to turn with the winds, the forces warping the aluminum struts and tearing off wide sections of fabric (Robinson 30-33; Rose 77).

The stricken LZ-2, despite the violence of the crash and the exposure to high winds, its rubberized-cotton hydrogen cells were almost entirely intact. (Wikimedia)

Journalist Hugo Eckener recounted that the old Count was utterly heartbroken, and beside the wreck of his airship claimed it was the end. He ordered LZ 2 dismantled. Eckener naturally thought this the conclusion to his story, which he would continue to believe until some days later, when Count Zeppelin came to visit him. While the Count often detested most of the journalists who covered his experiments, he saw Eckener’s work, which was mostly concerned with engineering, as honest and constructive. He offered to confer with Eckener directly on future projects, and invited him to dinner several days later. Eckener rightly surmised that Zeppelin was prepared to reveal something greater at their next meeting, and he was proved correct. The Count was preparing to develop a new airship to compete with the Prussian Airship Battalion’s semi-rigid design for a new military project (Eckener 12, 13). Eckener readily joined the project both as both a publicist and a consultant, with his position to encompass more of the airship project in the coming years.

While LZ 2 can’t be regarded as more than a cumbersome and tragic project, Zeppelin wasted little time in gathering up the resources to capitalize on the intense military interest that had arisen around the airship.

The Winner

Practically undaunted from the loss of LZ 2, Zeppelin raced to produce a new airship for the army. One might think that the partial success of LZ 1 and the solo-ill fated flight of LZ 2 would have disqualified him, but at this early stage in aviation, Zeppelin was a leading pioneer in airship design. Disqualifying Zeppelin was not an option, and so, he joined the competition alongside August von Perseval, and the Count’s old rival, Gross of the Prussian Airship Battalion. His competitors produced a non-rigid, and a semi rigid airship respectively. However, by the time the Military Airship commision began, Zeppelin was the only aspirant to have already built and flown their design. In this way, he held a considerable advantage ahead of his opponents, despite the military commision being biased towards semi-rigid airships. In many ways, Zeppelin had already won the competition before it had even begun, as his immense technical advantage was cemented by his military background. With his foot in the door, Zeppelin soon received a gift of 100,000 marks from the Emperor, gained 250,000 marks from a Prussian state lottery, and a Government interest-free loan of 100,000 marks (Robinson 31; Rose 90).

LZ-3 included a series of new control surfaces, seen here in its late configuration (Wikimedia)

Zeppelin’s only real competition was the Gross-Bassenach, a fairly uninspired semi-rigid airship, as while Perseval’s blimp was fairly practical, it had very little room for further development. With Eckener’s appeals in the press adding to his credibility, all Zeppelin had to do was cross the finish line before his rivals. The race to build LZ-3 was on, and to save time it would use the same hull as its predecessor, even reusing the propellers from the wrecked airship. While the airship would be built on the same lines as LZ 2, it carried with it serious improvements in regards to propulsion, maneuverability, and its hydrogen capacity. Dürr would increase its capacity to 11428 cubic meters and fit the new ship with a set of triple box rudders, two pairs of vertical stabilizers, and two pairs of elevators. These modifications were refined at the engineer’s own homemade wind tunnel and would greatly improve the stability and maneuverability of the ship. However, the airship still lacked a set of vertical stabilizers, mostly as a result of the dated aerodynamic theories the Count still stubbornly clung to. Regardless, the new airship flew spectacularly.

On its first flight on October 9, 1906, LZ-3 traveled some 111 kilometers for two hours and seventeen minutes. It too proved fast, with a rated top speed of 39 kilometers an hour, with a highest claimed, and likely overly optimistic, speed of 53. Though perhaps more than anything, it carried eleven people aboard and possessed a maximum useful load of 2812 kilograms (Robinson 32). LZ-3 not only proved that Zeppelin’s airships were capable of navigation in windy conditions, but that they could do so when loaded with cargo. Many within the government were impressed with Zeppelin’s results, including Major Gross who, in spite of their rivalry, recommended that the Count receive additional resources for his experiments. This wave of support led Zeppelin to offer LZ 3 to the Military with a promise to build them two more airships. He also followed this deal with a series of claims so optimistic and absurd, only his finance man, Alfred Colsman, would repeat them. One such claim was that he would soon build an airship capable of transporting 500 soldiers and use heated air in place of hydrogen (Robinson 33).

The military would decline the offer, and the Interior Minister would state that the government would purchase no airship incapable of making a 24 hour long endurance flight. However the Count still had an excellent position. Zeppelin had practically beaten out his competitors and now had a good deal of confidence in military circles. Even the Emperor himself was pushing airship development both to ensure the German military stayed ahead of the French and draw attention away from a series of scandals in his court. In more practical terms, they extended him a payment of 500,000 marks to pay for a new, expanded hangar, to be dubbed the ‘Reichshalle’ (Rose92).

Seeking the military contract, Zeppelin would have LZ-3 improved with the goal of reaching the 24 hour endurance threshold. Its easily damaged forward elevators would be moved higher up to the sides of the hull, and its rudders would be placed between the horizontal stabilizers. The latter were made more effective, and enabled the airship to take off heavier thanks to dynamic lift, and the former less effective, and less responsive at lower speeds. Stability was further improved by extending the triangular keel forward and aft of the control cars.

After the move to the Reichshalle, the airship was refloated in September of 1907. Its next flight was on September 24, where it spent 4 hours and seventeen minutes over the lake. Several more flights were conducted with a number of guests including Dr. Eckener, the count’s daughter Hella von Zeppelin, Major Gross of the PAB, a Naval Representative Fregattenkapitan Mischke, and the Crown Prince. Its most impressive flight was during Mischke’s visit, when LZ 3, then piloted by Dürr and Hacker, conducted an overland flight lasting seven hours and 54 minutes, turning back when their fuel ran low. It was a notably more challenging flight, as the inconsistent air currents overland and the up and down drafts caused some concern. This was to say nothing of the 152 m altitude they flew at. In spite of the challenge, they flew some 354 km over Lake Constance followed by the Ravensburg countryside. Despite their success, they did not reach the threshold, and by the end of the year the airship was in need of new gas cells, and their supply of hydrogen, which the PAB had provided, had been fully expended. Things were not helped by a winter storm which pulled the floating hangar from its moorings and pushed it ashore, damaging LZ 3 in the process (Robinson 34-36).

LZ-3 over the Bodensee during an early point in its career (Zeppelin)

While LZ-3 did not reach the Interior Minister’s goal, it drew international attention. Despite this, the acclaim it won abroad was nothing compared to the excitement it generated across Germany. The turn of the century was a period dominated by immense technological and industrial development, where countries sought to distinguish themselves through cutting edge developments. Where Britain had its gargantuan high speed ocean liners, America, its skyscrapers, and France its groundbreaking film industry, Germany would have Zeppelin’s airships. Amateur aeronauts and students formed clubs to travel to see the airships as they glided over the Bodensee, and among the upper classes there was likewise excitement as balls were held in honor of Zeppelin’s achievement, and there was even talk of events to be held over a 300 meters in the air (Rose 96). While LZ-3 failed to meet military standards, the funds for LZ-4 would come as a matter of course. Its success was taken as inevitable, and with this in mind, LZ-3 was placed in long term storage as work on the next airship began.

LZ-4

LZ 4 at the floating hangar (Library of Congress)

Zeppelin’s next airship was once again an incremental improvement on the previous design, this new model being built to meet the 24 hour endurance requirement. Its production began shortly after LZ 3 completed its last flights for the year, with the skeletal hull of the new airship being assembled in the old floating hangar at Manzell in November 1907. Construction was finished on June 17, 1908, after it had traded places with the damaged LZ-3 in the restored Reichshalle. LZ 4 was designed to increase the endurance of its forebearer, and improve its mobility and maneuverability. It was lengthened to 136 m to accommodate a 17th hydrogen cell, increasing the total volume to 15008 cubic meters, and it received a large rudder at the nose, but this was removed after test flights revealed the arrangement to be inadequate. The gondolas too were enlarged to fit a larger 110hp Daimler motor (Zeppelin 15). A small cabin was also added along the keel, which was connected to a rooftop platform for navigation.

LZ 4 first flew on the twentieth of June, during which the airship turned so poorly that it soon made its return to the hangar, after which the aforementioned fore rudder was replaced by a large, semicircular aft rudder. The succeeding trial flights on the 23 and 29th would prove well as to convince the Count to embark on his most ambitious journey yet. Zeppelin would take his new airship over the Bodensee and across the Alps to Lucerne, Switzerland on July 1st. It proved exceptionally well, making the 386 km journey in 12 hours, setting records for both distance traveled and time spent in the air. Zeppelin’s airship traversed the picturesque, but dangerously windy Alps, and was met by crowds in the Alpine city. After a set of maneuvers to impress the crowd at the lake, LZ 4 departed for home. This was made all the more impressive as the airship traveled into a headwind on its return flight to Manzell through Zurich. Only one problem arose, this being that once the fuel in the main fuel tanks for each engine ran low, the engines had to be shut off while they were refueled from cans, leaving the airship at half power for several minutes. It would, however, prove only a minor inconvenience in the greater scope of the journey. Dr. Eckener wasted no time in working the press to promote this newest achievement, ensuring generous articles in Germany’s leading, and competing, newspapers Die Woche and the Berliner Illustrirte Zeitung. Word soon reached France, Britain, and America, though it would only be an echo of the attention Zeppelin received within Germany. A week after his return, he received over a thousand telegrams for his seventieth birthday and King Wilhelm II of Wurttemberg, his longest and steadfast supporter, awarded him the Kingdom’s gold medal for the arts and sciences (Robinson 36 Rose 102).

LZ-4 lifts off (Loc)

The Swiss voyage would prove an immense success both in proving the airship a robust means of travel over otherwise rough terrain, and as a symbol of technological accomplishment which propelled the Count and his creation onto the world stage. As one might expect, the Count was now confident enough to attempt the 24 hour endurance flight which would ensure military interest, and allow him to sell his two airships. On July 13, 1908, LZ 4 was outfitted for the long trip and departed the next day, only to have to return after a fan blade broke on the forward motor. Further delays were caused when the airship collided with the hangar, resulting in damage to its hull and hydrogen cells. The next journey to Mainz was pushed back until August 4th, where it departed with incredible fanfare.

LZ 4 left with a crew of eight, which included Dürr, its designer, the Count’s old friend Baron von Bassus, and three veteran engineers, Karl Schwarz, Wilhelm Kast, and Kamil Eduard Luburda. They departed before an immense crowd, the largest share of which came from a nearby resort. Zeppelin, rather uncharacteristically, eschewed the typical maneuvers over the lake, and instead ordered the ship to its next destination at its best speed. LZ 4 would overfly several towns to the delight of crowds who were gathered by telegraph reports and special newspaper editions. In spite of the fanfare, trouble began in the evening when the engines began to run rough around 5:24 PM. After setting down at a quiet spot near Rhine at Oppenheim, they set off again, only for a more dire failure to crop up at 1:27 the following morning. Its front engine was shot and the rear motor was sputtering and smoking, having expelled what little remaining oil was aboard. With Stuttgart tantalizingly close, Zeppelin brought the ship down outside Echterdingen, around ten and a half kilometers outside their final destination. While they waited for a team from a nearby Daimler workshop, a crowd grew.

News of the grounded airship spread fast, and soon tens of thousands had begun to move. Thousands poured through the small town on bikes, carriages, wagons, and cars with the hope of seeing the airship. In all, some fifty-five thousand would assemble to see the Count’s airship, with some even being recruited by Schwarz to set up a make-shift anchor out of a carriage to hold the airship in place. The rest of the crowd was kept to a safe distance by what policemen and soldiers could be mustered. At around noon, concerns arose as the sounds of a thunderstorm made themselves clear. These concerns were soon justified as gusts of wind soon followed and began to pull the airship away from its moorings. The gale pulled the airship around the clearing as soldiers desperately worked the mooring ropes and the Daimler mechanic became worried enough as to leap from the front engine car. Schwarz worked his way through the catwalk and began to release hydrogen to prevent the airship from being carried high and away by the storm. He succeeded, but was unable to stop the winds from carrying the airship across the field into a stand of trees. Gas cells were shredded, the framework twisted, and in an instant the ship was alight. Schwarz lept, and in a terrifying moment on the ground, found himself covered in burning net and cloth. Miraculously, the mechanic cast off the debris and crawled through the burning wreck and, in his own words, ‘ran like hell’. Apart from Schwarz, a soldier, and his fellow mechanic, Laburda had also escaped the airship. The latter was merely singed, and the former left unconscious. Fortunately, there were no fatalities and those injured received prompt medical attention (Rose 108, 109).

The aluminum from LZ-4 being carted off from the site of the accident. (Wikimedia)

 

The crowd was horrified and left utterly dumbstruck having witnessed the destruction, and forlornly surveyed the wreckage. Zeppelin and the rest of the crew were similarly dismayed, having returned to the site from their hotel in Echterdingen and finding the warped aluminum frame of the airship across a charred stretch of Earth. The future British PM David Lloyd George was among those gathered, and having traveled hoping to see the airship would only find its remains. He would state “Of course we were disappointed, but disappointment was a totally inadequate word for the agony of grief and dismay which swept over the massed Germans who witnessed the catastrophe. There was no loss of life to account for it. Hopes and ambitions far wider than those concerned with scientific and mechanical success appeared to have shared the wreck of the dirigible. Then the crowd swung into the chanting of Deutschland uber Alles with a fantastic fervor of patriotism.” (Rose 110,111).

Dejected, the Count and crew returned to their offices in Friedrichshafen. They could have hardly expected what was waiting for them there.

The Miracle

While the accident had largely reinforced the skeptics in official circles, the public was not willing to let Zeppelin’s work come to an end. In the aftermath of the tragedy, thousands began organizing donations. What had begun with an off the cuff speech by a Stuttgart merchant Manfred Franck, to rouse the public to help build Zeppelin’s next airship, had become a national phenomenon. Soon the press echoed his words and were raising thousands of marks a day, and they were not to be outdone by public and private associations who alike, sent hundreds of thousands of marks to Zeppelin AG. Those who hadn’t the money, sent clothes, food, and liquor of varying quality, and had done so in such amounts that the resort town’s post office was incapable of sorting it. Following Zeppelin’s return to his offices in Friedrichafen, he had received some 6,096,555 Marks from the public (~$25-30 Million USD 2020).

Perhaps even more bizarrely, came the Government’s response. Despite Zeppelin’s inability to perform the 24 hour flight, they were interested in purchasing the rebuilt LZ 3 and commissioning a new airship of the same design as LZ 4, to be accepted into service under the designation Z-2. The Emperor himself would soon visit the Reichshalle hangar to inspect LZ 3 and award Zeppelin with the Order of the Black Eagle, the highest order the Kingdom of Prussia could bestow. In a further and ironic twist, he was also invited to the Imperial War Games, or Kaisermanover, where he accompanied the Crown Prince (Robinson 41-43, Rose 113, 114).

 

LZ-3 was the first airship to be sold to the German Military, where it spent many years in service. (Wikimedia)

Almost impossibly, Zeppelin had been propelled far further by his greatest disaster than he had his greatest success. Zeppelin had both the love of the public and  a powerful presence in the halls of Government, and with his gifted fortune, he set off to expand the horizons of what was once a personal project. On September 3, 1908 the Count founded Luftschiffbau Zeppelin Gmbh, or Zeppelin Airshipworks Inc. What was once a small, dedicated team running out of a handful of facilities along the Bodensee, was transformed almost overnight into an industrial powerhouse. In the following years and under Colman’s direction, he founded a number of new enterprises under the parent company which would include the Maybach Motor Company in 1909, Ballon-Hullen-Gesellschaft of Berlin Tempelhof in 1912, to build hydrogen cells, Zeppelin Hallenbau of Berlin in 1913, to construct hangars, and Zahnrad-Fabrik in 1915, to build gear and drive shafts (Robinson 41, 42). At the center of all of this sat Friedrichshaven, which became the hub for all of these projects, and by 1914 the small resort town would grow to become the wealthiest city in Wurttemberg. As the headquarters for the new company, it would boast new homes for the workers, along with schools, groceries, a pub, and a performance hall. On top of all of this was a generous company life insurance policy, and free room and board for the families of workers who found themselves struggling.

In the months following the new founding of Zeppelin Airship Factory in 1908, the newly christened Z I (formerly LZ 3) was delivered to the army, where it served until 1913, along with the newly built Z II, its company designation being LZ 5. Z II was completed in May 1909 and was identical to its ill fated predecessor save for the omission of the ventral fin along the gangway, the cabin, and the installation of additional fuel tanks. Before it was delivered to the army, Zeppelin wished to demonstrate its capabilities with a 36 hour flight to Berlin. The flight began in earnest after two aborts, on May 29, 1909, and the airship proceeded through a dark and squally night on the way to Ulm. From there they once again met frenzied crowds as they traveled around Augsburg, Nuremberg, and Leipzig before having to turn back as the fuel supply was inadequate, with the flight being terminated at 21 hours. It was not, however, insufficient enough to prevent them from flying around and circling Bitterfield, the headquarters of their rival firm, Parseval. Apart from the airship receiving damage from landing on the only pear tree in a field during a night landing, which punctured the forward gas cells, they returned home with little else to remark upon. Following repairs, it was ready again on June 2, though it would not attempt a second flight before the army came to accept it on July 24. In service Z II would see no true military duties, but it would be a considerable tool for generating notoriety for the service. Its high point was a demonstration at the International Aviation Exposition held in Frankfurt am Main, in September and October of that year. Generally, the army did not consider any of the airships they were provided with suitable for general service and would not procure any more until new models were built. They would largely be proven right when Z II was shredded while grounded during a storm, with Zeppelin’s outburst over the army’s carelessness bringing his relations with them to a new low (Robinson 47, 58).

Regardless, Zeppelin sought to renew military interest with LZ 6. Once again, this airship was derived from LZ 4, though the heavy lateral driveshaft gears connecting the engines and propellers were swapped with a steel band drive to save weight, it used more powerful 115 hp engines, included passenger accommodations in the cabin, and lacked vertical stabilizing fins. A short fabric ‘rain skirt’ was also installed around the hull to prevent rain water from dripping on the occupants of the gondolas, but it was removed as the crew felt it unduly lowered the airship’s top speed (Robinson 49). Its similarities to the three previous airships was likely an influencing factor in it receiving no trial flight. Instead, Zeppelin would fly the airship straight to Berlin on its first outing for the Whitsunday holidays. Unlike his attempted flight in LZ 5, he would not be able to turn back, as he was expected to arrive at Tempelhof Field where the Emperor awaited him. He was firmly reminded of this in a series of demanding telegrams from the Emperor, something the Count would have to heed now that he was in the graces of the court.

Count Zeppelin with his airship during the Berlin trip. (Bundesarchiv)

The airship departed August 24th at the command of Dürr, the Count having recently undergone surgery and unable to make the flight until after the airship stopped to refuel at Bitterfield. Trouble arose several hours after departure, as the lighter steel band drives immediately showed themselves to be less durable than the bevel gears. A former navy man, Helmsman Hacker was able to repair the drive, but several hours later a cylinder crack stopped one of the engines. The airship stopped at Nuremberg, awaiting a mechanic from Daimler, this detour leaving them unable to depart until the 28th. Similar problems persisted with the drive bands, but the airship would make it to Berlin on the 29th, though not in the best state (Robinson 50). However, the crowds assembled there took no notice and upon landing at Tempelhof, Zeppelin shook hands with the Emperor as the crowd cheered. The Count would also meet Oliver Wright, famed American aviator and co-inventor of the airplane, though the two would see very little promise in each other’s work (Rose 120,122). The Count and LZ 6 would remain on the public tour for some weeks, and it required a good deal of work to get the airship running well again. They went so far as to borrow the propellers from the army airship Z II. After giving the first aerial tours of the city to members of the Reichstag and public officials around the country, LZ-6 would return again to the hangar at Manzell before being presented at the 1909 International Aviation Exposition at Frankfurt in September. From a temporary shed built on the grounds, the airship gave passenger flights up and down the Rhine. These flights attracted little military interest but captivated the public, and to them, it seemed that the long awaited dream of air travel had been made a reality.

LZ 6 from bellow. (Wikimedia)

LZ 6’s return would see it sent to a new tent shed at Friedrichshafen, with the former floating hangars to be dismantled. With its publicity tour over, Zeppelin sought to rebuild the airship in the hopes of selling it to the military. A third engine, a Maybach 150 hp model, was added in the former passenger cabin which was geared to a pair of hull mounted propellers, allowing it to make a new top speed of 58 km/h. This was later removed for some time after it was believed to be a fire hazard, being mounted so close to the ship’s hydrogen cells. LZ-6 would also temporarily receive an experimental radio set, though the sum of these modifications would be altered again in the spring when the ship was dismantled and rebuilt. It was lengthened by eight meters, the third engine was reintroduced in the rear engine car, and the stabilizers were reworked. The biplane stabilizers at the back were combined into a single, large stabilizer, from which the elevators and rudders hung. The aft ‘barndoor’ rudder was also removed, with a fixed, vertical stabilizing fin taking its place. In all, the ship could now make 56 mk/h and was far more stable in flight. This however, was not enough to convince the army to purchase it.

With the failure to sell more airships to the military, Zeppelin was in a bind. While the extremely generous public donations could keep him afloat for the time being, he would need to find a means of consistent income for the company. Colsman, the corporation’s finance chief, had a brilliant solution. Given the public’s incredible enthusiasm for the airships, naturally they would prove the ideal customer base, and thus he proposed the Deutsche Luftschiffahrts-Aktien-Gesselschaft (DELAG), or German Airship Transport Company. In other words, the world’s first airline.

The First Airline

Zeppelin detested the idea, as he considered his airships the weapon to make the German army unparalleled in field and to boost the prestige of the country by carrying the flag, just as the expanding German navy did. While he had once considered civilian applications for the airship in the 1890’s, years in the limelight and his rehabilitation in military circles had firmly shifted his view, to him, the airship was first and foremost a weapon. However, Zeppelin Gmbh. was not the small outfit driven by one unshakable nobleman like that which preceded it. The decision went before the board of directors, who decided in favor of the airline. DELAG was founded on November 9, 1909 with the hope of beginning operations in the summer of the following year.

The shrewd and energetic Colsman proved right, and it wasn’t long until he had amassed the three million mark starting capital and the backing of the famous Hamburg-America shipping line, who would be the primary means of ticket sales and advertisement. Many larger cities soon sent requests to be included, with the mayors of Frankfurt, Cologne, Dusseldor, Baden-Baden, Munich, Leipzig, Dresden, and Hamburg soon joining the airline’s board of directors, and with several seeing to it that airship sheds were assembled in their respective cities (Robinson 52, Eckener 15). While orders for commercial airships were placed, they proceeded to organize the first operations using LZ 6 and the newly completed LZ 7 ‘Deutschland’.

Deutschland was built along the same lines as the modified LZ-6, and was the first to carry passengers for the airline. It was a stretched design some 148 meters long with a capacity for 19,340 cubic meters of hydrogen and a useful lift of 4,990 kilograms, with up to 1,496 kilograms of that being fuel. However, its real innovations were found in the once austere sightseeing cabin. The former canvas box was now a comfortable sitting and viewing room, which was of high layer plywood construction covered in mahogany sheets with mother of pearl inlays on its pillars and ceiling beams. The carpeting and comfortable wicker furniture added to the finery, and given the length of the flights, a small galley with matching aluminum cutlery was also wisely included. Lastly, it was the first to carry a lavatory, it also being aluminum to save weight. Behind all of this were a series of aluminum struts and cables which anchored it firmly to the hull (Robinson 55, Rose 134).

The Deutschland was still very much a derivative of LZ-3, which while versatile, was dated. (Wikimedia)

It was captained by former Prussian Airship Battalion Captain Kahlenhberg, as despite the several airships flown over the years, there was no sizable pool of experienced aviators to recruit from. The foremost of these were Zeppelin himself, who could not be convinced, and Dürr, who was otherwise occupied in his role as head designer for the firm. The first flight would be to Dusseldorf, the city which managed to complete their hangar first. It was scheduled for June 28 with a passenger list of 23, mostly journalists who had been invited by Colsman. The expectation was a flight of three hours, which began after a breakfast of caviar and champagne. Unfortunately, the crew had departed without a weather report. After the failure of an engine, the ship was left floundering in higher than expected winds. Deutschland struggled for hours through turbulence, violent gusts, and rain with one officer making the mistake of telling a concerned passenger ‘we do not know what will happen.’ Captain Kahlenburg was unable to prevent the underpowered, unbalanced airship from making a crash landing in the Teutoburg forest. Thus ending the short stopover flight that became a nine hour endurance test for everyone aboard. Apart from a crewmember who made a dramatic leap from the rear gondola, and fractured his leg, there were no injuries. Understandably, the journalists’ impressions were quite poor and the airship was disassembled and shipped back to Friedrichshafen where it would be rebuilt (Robinson 56 Rose 136).

Kahlenburg was laid off, and in his place Dr. Eckener became both a pilot and head of flight operations for DELAG. His first action was to familiarize himself with airship piloting on LZ 6, making some 34 flights, though this airship was soon damaged beyond repair after a fire in its hangar. With this accident, hopes were placed on the up and coming LZ 8 Deutschland II, made mostly from the reclaimed material of the previous ship. LZ 8 was identical to its ill-fated predecessor, and was likewise as ill-fated. With Eckener at the helm on its first passenger outing, he allowed himself to be pressured by the crowd to bring out the airship in a dangerous crosswind. Deutchsland II was subsequently knocked alongside the hangar and bent out of shape. Eckener claimed this cured him of all recklessness thereafter, and he subsequently went to completely reform flight operations at DELAG (Eckener 16).

The rebuilt Deutschland was met with an end that was as embarrassing as it was avoidable, but it thankfully motivated such a strict safety regimen that DELAG never suffered such an accident again. (Wikimedia)

Dr. Eckener isolated the causes of accidents that had plagued operations thus far, and focused on ensuring that DELAG airships would be crewed by veteran airmen who would have the benefit of extensive weather reports and more reliable equipment. The board was willing to give it another try, and authorized the construction of a new, modern airship. This new ship was LZ 8 Schwaben, which was shorter, more maneuverable, had a useful capacity of 6486 kilogram, and used new 145hp Maybach engines which would prove far more reliable. It made its first, and very promising, trial flight on June 26, 1911 where it made for 75 kilometers an hour (Robinson 59). Many of these advancements came as a result of Dürr accepting a variety of new concepts from junior designers, key among these was in rejecting the continuous lengthening of airships to boost their lift, and placing a greater focus on theoretical testing and problem solving, rather than building a ship and continuously modifying it as difficulties arose.

Schwaben was the first Zeppelin to have all its control surfaces at the rear, where they would remain on all future Zeppelin airships. (SFO Museum)

Along with the new airship came a series of reforms to DELAG’s flight guidelines. Crew training was standardized and captains in particular were required to have a thorough understanding of their vessels and to have participated in 150 flights before they would be allowed to command an airliner. The training program would be so successful that the military would send their crews to train with DELAG during their off season. Some would even fly passengers during the airline’s regular service (Rose 138). These procedural improvements were to extend to the ground crews, both to improve the tricky process of moving an airship in and out of its shed, and to avoid the kinds of accidents such as the one which claimed LZ-6. In that case an unmarked can of gasoline was thrown over a fire in the hopes of dousing it. Facilities were thus overhauled and staffed with thoroughly trained professionals. Perhaps most importantly of all were the stations for meteorological reporting. Unlike Kahlenberg, future DELAG captains would benefit from near nationwide weather reports from the series of meteorological stations which captains could contact at any time over the radio. Even without the radio they would have access to wind maps which charted the typical currents over Germany and allowed captains to safely determine new courses should their first choice be unavailable. Should all else have failed, emergency depots were established along common routes where airships could stop for repairs and fuel.

In order to avoid accidents while departing the hangar in a cross wind, the airships were tethered to trolleys called Laufen Katzen, or running cats after being likened to cats running across the top of a fence. (SFO Museum)

With these improvements, Schwaben was well equipped when it began passenger service in the summer of 1911. With all the methods worked out and potential dangers addressed, passenger flights went off without a hitch. A typical flight saw passengers assemble early in the morning, when winds were at their weakest, and allowed them to see the airship as it was serviced and brought out. When they departed the airship was almost impossibly smooth as it pulled away from the ground and began its journey. While the passengers traveled to a variety of locations and took in the view they were provided with a series of refreshments. The meager provisions aboard Deutschland paled in comparison to what Schwaben’s passengers enjoyed. Along with a considerable wine list that boasted a selection of Rhine, Moselle, and Bordeaux along with champagne, passengers were served a selection of cold dishes such as caviar, Strasbourg pate de foie gras, and Westphalian ham (Robinson 59). All of this was enjoyed in relative silence as the canvas skin and hydrogen cells dampened the sound from the propellers.

The main attraction beyond all of this was the view of the country from the air, as while this was a passenger service, its lack of fixed schedules could mean a wait of several days as weather cleared or repairs were made. Tickets too were steeply priced, owing to the limited number of seats aboard and high operating costs. A ticket could cost between 100 to 600 marks depending on the destination, though many passengers didn’t pay for their own seats as they were invited to garner publicity for the service. It was very common for periodicals and newspapers to send their own aboard to gather material. Along with journalists were VIPs, such as notable public figures, and foreign dignitaries the state wanted to impress. Those unable to purchase a ticket had the option of watching one of the many films made aboard the airliners or visiting one of the many DELAG airports located across Germany.

In the several weeks following its entrance to service, Schwaben was a hit. After the miserable year of 1910, it seemed as if the airline had not only been improved, but practically perfected.

The Golden Years

Viktoria Luise would introduce a number of notable improvements, chief of which was a larger passenger compartment. (Wikimedia)

As Schwaben was refitted following its stowage in the previous winter, it was joined by a slightly larger airship, LZ 11 Viktoria Luise. Named for the Emperor’s daughter, its design and performance were nearly identical to the Schwaben, save for its redesigned elevators and rudders. The year would start well, though an accident would leave Schwaben burned on June 28. It was traced to a static discharge caused by the rubberised fabric which formed its hydrogen cells. No one was aboard the grounded airship, though the public was momentarily disquieted. To allay fears, the Dusseldorf maintenance team took the blame while Colsman quietly shifted to the use of cells made of cotton and goldbeater’s skin. This material was a finely woven cotton fabric laminated with chemically treated sheets of cow intestine, which while unpleasant to produce, was lighter than the rubberized fabric while remaining just as durable, and removed any chance of static discharges (Chollet 6). Apart from the loss of Schwaben, operations continued without trouble for the remainder of the year.

Operations were expanded by a new airship, LZ 13 Hansa, named for the medieval Hanseatic league of merchants which spanned the Baltic. Identical to the Viktoria Luise, it was completed July 30 and took Schwaben’s place. For the remainder of the year Viktoria Luise and Hansa operated out of the double hangar built in Hamburg, where at the end of autumn, they were used to train the first Naval air crews. At the end of this training period, Hansa was flown over the High Seas Fleet Parade and the naval maneuvers that followed it. Ironically, Zeppelin’s civilian operation had managed to capture the military’s interest more so than any direct appeal.

Passengers sightseeing aboard Hansa. (Ryan Smith)

By the start of the 1913 season, DELAG was an international sensation, and in Germany, a technological achievement of immense pride. Shortly after Hansa and Viktoria Luise had entered service, they were joined by LZ-17 Sachsen. This ship, named for the region it would service, was slightly shorter than its contemporaries though built with a wider diameter, and held the highest lifting capabilities of the three . It was completed on May 3, 1913 and was sent to a shed at Leipzig where it operated from thereafter (Robinson 333). During the summer season all three ships were in service, and each operated out of its own region. Hansa left Hamburg for Potsdam, to service Berlin, and Viktoria Luise was sent to Frankfurt.

Hansa comes in to land. (Wikimedia)

These regional flights would ensure the airships were seen over and around most of Germany’s largest cities. What was once a curiosity that rarely strayed from the Bodensee was now a common sight for millions of Germans, one that stirred both patriotic fervor, and a curiosity and optimism for what the future held. While a relatively small proportion of Germans would ever fly aboard these airships, they drew massive crowds around the cities they visited and at the sheds where they were stored. Sadly, the entire enterprise was cut short by the beginning of the Great War, and the airships were turned over to the military during the period of general mobilization. Practically overnight, DELAG had ceased to exist, and in the end, it’s difficult to know how successfully DELAG would have been had it continued to operate its three airships. When its airships were pressed into military service, the company was still operating in the red, though its operating costs were plummeting and the proportion of paying versus invited passengers had climbed steadily. Regardless of its financial forecast, DELAG’s technical achievements would not be rivaled again for over twenty years. Its airships carried a total of 34,208 passengers over a distance of 1,172,529 kilometers, nearly five times the Earth’s circumference (Rose153).

The Zeppelin at War

Despite the Count’s enthusiasm that his airships would prove a decisive weapon in any war to come, this would not prove to be the case. In the years DELAG was operating, the German military had received a number of airships, though they never effectively developed their offensive capabilities. Both the Army and the Navy possessed a small fleet of Zeppelin airships, each with very different missions in mind, with the Army placing an emphasis on bombing, and the Navy on reconissance. In contrast with the well coordinated and professional civilian operation, both the Army and the Navy would suffer numerous accidents, the worst of which befalling the Navy’s L.2. The ship burned as a result of design choices from the Naval representative, Felix Pietsker, who was at Friedrichshafen to oversee its construction. He demanded the airship’s keel be placed within the hull to streamline it and bring the engines in closer to the hull, both choices being strongly criticized by Dürr as being unsafe. During a test flight, the inner keel collected leaking hydrogen, which otherwise would have exited through the top of the airship, and was subsequently set alight by the heat of the engines. All 28 aboard would be the first to die on a burning airship, and with the war on the horizon, they would not be the last (Rose 151).

Most surprisingly, no specialized weapons were developed for the airships, which as bombers first carried 15 and 21cm artillery shells which were ejected from the airship over the target. These were used by the Army’s Zeppelins in the opening weeks of the war, but it soon became clear that these low flying airships were too vulnerable to groundfire to be of any real use (Robinson 86). This realization would push airship design evolution faster than any previous motivator. Among the first major new additions were the cruciform tail sections added to the M-Class airships. This feature had been pioneered by the rival Schuttz-Lanz airship company, and would markedly improve the handling and aerodynamics of the airship. Previously, Zeppelin’s had blunt tail sections, which were initially believed to be aerodynamically superior, but the taper on the newer models allowed for far better stability at speed. Enclosed gondolas were also added, being more or less essential for long patrols over the sea. Perhaps the most important of all was the introduction of duralumin on LZ 26 which enabled the construction of larger and stronger airship hulls (Robinson 89). The first airships to combine all of these features were the P-Class ships, which were very capable maritime patrol aircraft and were used on the first raids on London.

L12, a P-Class airship, the class would prove to be excellent naval patrol vessels and far more comfortable for their crews over the older, open gondola ships. (IWM)

As strategic bombers, the Zeppelins were ineffective. While at first they were surprisingly resilient to bullets and artillery splinters, the introduction of better training for anti aircraft crews and special phosphorus-core bullets for aircraft would see them fight a losing battle that would only end weeks before the war itself did. Zeppelins were built to fly ever higher to try and avoid these threats, and they flew their raids at night to try and avoid detection and artillery spotters. They would fail, but they would produce much more robust and versatile airships which remained very capable maritime patrol aircraft. The prime of these being the R-Class.

These ships entered service in 1916 with a host of new improvements. The new class did away with the long, inefficient cylindrical sections in favor of a teardrop shape which both reduced drag and vastly increased internal capacity. They were also the first to carry six engines, these being Maybach HSLu motors capable of producing 240Hp which gave them a trial speed of roughly 60 kilometers an hour. The hydrogen controls too were improved, with a responsive electric control system allowing for more precise and sensitive inputs, which were necessary when the airship operated at or above its maximum loaded ceiling of 3962 meters. In all, virtually every aspect of these ships had been improved (Robinson 120. Stahl 84-89). Unbeknownst to the German Navy, who were looking for better bombers to wage their ineffectual nightly war, Zeppelin had built a truly exceptional intercontinental aircraft.

The R-Class possessed a revolutionary teardrop hull shape, which vastly improved its aerodynamic qualities over the previous cylindrical forms. (Hauptkull)

On the night of July 26, 1917, Captain Ernst Lehmann set out on the longest patrol of the war thus far. With the standard R-Class airship, LZ 120, he patrolled the Baltic Sea for 101 hours. This ‘experiment’ was conducted with a considerable load of 1202 kilograms of bombs, 16918 kilograms of fuel, with a crew of 29. With his men divided into three watches, and running only three engines at a time, LZ 120 endured poor weather and successfully enacted engine repairs, all while dodging thunderstorms. When they returned to their base at Seerappen, the airship remained in good condition with enough fuel in its tanks for 14 more hours (Robinson 251, Stahl 89). As astounding as this feat was, it would soon be outdone.

In light of Lehmann’s record setting patrol, the German army now looked to the Zeppelin to undertake a truly groundbreaking mission. It seemed to all that General Lettow-Vorbeck’s troops, alone in Africa and low on supplies, were fighting on borrowed time. It was clear that the only way to reach them, and deliver vital supplies, was by airship. Thus a specially modified R-Class airship was prepared, L-59, which was lengthened and lightened to carry out the special mission. The 750 foot airship was to fly to Lettow-Vorbeck from Jamboli, Bulgaria, to the beleaguered general some 7000 kilometers away. It carried approximately 16,238 kilograms of cargo, and would be disassembled with its aluminum and fabric repurposed into radio towers and bandages. KorvettenKapitan Ludwig Bockholt set off from Jamboli on November 21, 1917 under strict radio silence. They passed through thunderstorms over the Mediterranean before crossing into North Africa, which would prove even more treacherous due to the updrafts which threw the ship about over the deserts. The heat too caused excessive hydrogen loss which had to be offset by dumping large amounts of ballast. They would cross the desert and receive a signal from Berlin, advising them to turn back as Lettow-Vorbeck’s forces had been defeated. In reality, the guerrilla general had pressed on into Portuguese Mozambique, where he had gathered the supplies he needed. Bockholt ordered the ship back with some arguments among the crew, and was back in Jamboli on November 25. In all his ship had been airborne for 95 hours and had traveled some 6760 kilometers, and upon its return still carried enough fuel for 64 hours more (Robinson 253-255, Stahl 90-91). Theoretically, L59 could have traveled to Chicago one way from Friedrichshafen, or potentially to New York and back.

The lengthened L59. (Hauptkull)

The rapid advancements in airship design during the war were incredible, though their use against civilians would leave a black mark which they could never truly wash away. England in particular bore deep scars as a result of the ‘baby-killers’, and as if to mark the end of an era, Zeppelin had passed away in March of 1917 at the age of 78. Despite the dark turn his invention had taken, many still viewed the count favorably, and in a May 1917 edition of the New York times he was placed as an equal alongside the Wright Brothers and praised for the years of dedication and disappointment he had spent honing his creation (Rose177). In the end, the war would cripple airship production and design in Germany, as the state was subsequently banned from operating large airships, and many of its Zeppelins were turned over to the Allies or destroyed by their crews. Many airship veterans, and even historians, would continue to state decades after the war, that the raids over England held down ‘a million men’ from being deployed to the continent. In reality, by June of 1918, Britain had exactly 6,136 men devoted to home air defense, and the total wartime damages from strategic bombing amounted to 1.5 million GBP. This compares rather poorly to the equivalent of 13.25 million GBP spent on airship construction, to say nothing of the hundreds of Gotha and Zeppelin Staaken biplane bombers built (Rose 173).

 

The Crossroads

Without their primary customer, and more or less totally banned from building their main product, the Zeppelin company was seemingly at the end of the line. Colsman, seeking to rapidly increase revenue, attempted to pivot the enterprise away from airships towards cars and consumer goods, regardless of the anger from the true believers in the firm. However, the economic crises that emerged in Germany after the war rendered the plan hopeless; there would one day be a market for luxury Maybach cars, but it was very far off.

A brief power struggle in the company ensued with Dr. Eckener becoming its head over the firebrand Captain Lehmann, who had taken part in destroying several Navy airships which were to be turned over to the Allies. Dr. Eckener found a loophole in the treaty which threatened to destroy the company; while Germany wasn’t allowed to possess an airship, the Versailles treaty did not explicitly prevent any private enterprise from building or operating airships of their own (Rose 194). With this in mind, Eckener approached Dürr and his engineers to design a new airship, one which could in no way be used for military purposes. Thus it seemed that DELAG was poised to return almost as suddenly as it had vanished back in 1914. Initially, there were plans for a trans-atlantic airliner based on a massive wartime X-class airship, but its proximity to a military design was too problematic, not to mention expensive. They accordingly settled on a small design with regional ambitions.

A model of LZ 120 is prepared for wind tunnel tests. (Wikimedia)

The design work for LZ-120 Bodensee, named for the lake from which the first Zeppelin’s flew, was completed on March 10, 1919 and first flew that August. Its design was the most efficient of any airship built up to that point, as despite being considerably shorter than the airliners that preceded it, at around 120 meters, it possessed an incredible useful lift of 44,678 kilograms and had a trial speed of 132 km/h, thanks to its four 245hp Maybach IVa motors. Perhaps most impressively of all, it could fly in all but the worst weather (Eckener 201). When fitted out for service, it was laid out in a manner similar to a passenger train within the combined cabin and control car. It possessed five compartments seating four, and one VIP cabin in the front who paid double fare. Six more seats could be fitted if the partitions were removed. As with the previous airliners the cabin was well furnished with a fine wood paneling over the structural elements and specially made aluminum and leather chairs for the passengers. At the rear of the gondola were the washroom and buffet (Robinson 258 Rose 196).

The small but quick Bodensee. (George Grantham)

When DELAG resumed service in the fall they began operating on fixed scheduling, which was made possible owing to Bodensee’s reliability and ability to fly through rain and wind. The sightseeing flights were done away with and replaced with a regular passenger route which ran from Friedrichshafen to Berlin with a stop in Munich. Generally speaking, the lax margins for luggage that existed in the pre-war DELAG were also done away with fees being added after 13 kilograms. On one occasion, a woman wearing extravagant furs brought nearly a dozen trunks aboard and tried to protest the fees which greatly exceeded that of the original ticket. In order to make up for slack during slow periods, mail was carried in place of passengers. Overall, Bodensee proved very effective, earning 500,000 marks in its first month, placing it on the road for long term profitability (Rose 196). Typical passengers were state officials, Zeppelin company personnel, and foreign visitors who could not depend on the rail network, which had been racked by strikes, coal shortages, and damaged infrastructure during the revolutions of that year.

Likely owing to tastes tempered by wartime hardships, Bodensee’s decor was subdued and looked to serve a more professional class, rather than the pleasure seekers of the Pre-war DELAG airships. (Bundesarchiv)

Eckener saw these routes as only the beginning and traveled with the airship to Stockholm in October. There he received an enthusiastic reception where he sold tickets for flights on the yet-to-be completed LZ 121 Nordstern. This was to be just the start, for the real destination for his airline was Spain. In the long term, however, his hope was in crossing the Atlantic. The Zeppelin’s long haul capabilities were well proven and shorter flights could be serviced by more modern planes, which by the mid 20’s could be flown with some semblance of safety and comfort. With long term plans seeming coming to fruition, DELAG completed the season’s operations in December, having flown on 88 out of 98 days for 532 hours, over 51,981 kilometers, and servicing 4,050 passengers. LZ 120 was placed in maintenance to be lengthened and have its control surfaces altered to compensate for its oversensitive yaw characteristics (Eckener 200, 201 Rose 198). However, these plans were not to be, as the loophole that allowed these operations was closed.

1919 was a chaotic year for most of Europe. In Germany, mass strikes of workers, and mutineers from the Army and Navy, launched a short-lived revolution in Germany after the Emperor fled and his government collapsed. (National Archives)

The Allied commission had ruled in January of 1920 that DELAG was not authorized to fly airships under the Versailles treaty, and they were instructed to turn their two airships over to France and Italy, who were to have received Navy Zeppelins that had been destroyed by their crews. Dr. Eckener would claim this was a protectionist ruling, given that the Allied commissioner, Air Commodore Masterman, was also in charge of Britain’s own flagging airship program. In any case, LZ 121 was christened Mediterranee in French service, and subsequently dismantled in roughly a year. Bodensee however, would spend many years in Italian service as the Esperia. While it never returned to regular passenger service, it made flights from time to time at numerous civil and military events from its shed in Ciampino near Rome. Most notably it accompanied the polar exploration airship N1 as it traveled to Barcelona, Spain, flew from Rome to Tripoli and back in 24 hours, and was shown to Japanese Crown Prince Hirohito during his visit in 1921. While most reparation airships were neglected and dismantled in the years following the Great War, Esperia seems to have been well maintained until it was decommissioned on July 18, 1928 (Robinson 350).

Esperia a few weeks before its decommissioning after nearly ten years of service. (Bundesarchiv)

 

With Bodensee and Nordstern out of their hands, Zeppelin seemed to be running on borrowed time once again.

The Zeppelin, Banned

Zeppelin was in trouble, but there would soon be an opportunity for them to get back on their feet. While the British airship program was largely dysfunctional, it had managed to garner interest in the technology. Their own R.34, which was largely a reverse engineered R-Class Zeppelin, had managed to cross the Atlantic, though with worrying slim margins for fuel. For the time being, the British built on this achievement with the pending sale of R.38 to the US, which subsequently was renamed ZR 2. Given American interest in the technology, Dr. Eckener offered to build the United States an airship to compensate them for the one which was promised to them under the Versailles treaty, but which its crews destroyed. The US Navy jumped at the offer and offered to pay 3.56 million gold marks for the airship, though they were stopped by Air Commodore Masterman who refused to allow the construction of the airship in Germany. This block would remain until the US Navy was preparing to receive the ZR 2.

While the British were able to replicate German airship technology, they understood it exceedingly poorly. R.38/ZR-2 was based on a high altitude airship design with a hull that was designed to be maneuvered only at high altitudes, as its beams were made thin to reduce weight. While ZR-2 was proceeding with its final trial flight, its hull shattered during a low altitude turn at 99 kilometers an hour and it exploded. Of its 42 crew and passengers, only 5 survived. The US Navy was outraged. They directly accused the British of protectionism with the intent to force them to purchase their dangerous aircraft, and in the maelstrom of backlash, the German airship ban was lifted. The US Navy and Dr. Eckener soon agreed to an airship specified to be only used for civilian purposes, and that Zeppelin would shift production to consumer goods after it would be completed. All involved knew that neither clause would be observed, but Masterman was forced to accept their terms regardless (Rose 221, 222).

The US Navy soon sent representatives to Friedrichshafen to oversee the design and production of LZ 126/ZR-3. The partnership between Zeppelin and the US Navy proved amicable in 1922, and eventually it was agreed to establish a US based entity for airship production, Goodyear-Zeppelin, the following year. Work on the new airship progressed as smoothly as one could have hoped during such difficult times.

LZ-6 is brought into the Lakehurst hangar for the first time. It was soon to be rechristened as the USS Los Angeles. (Wikimedia)

ZR-3 was launched in 1924, the large airship looking akin to a much larger, and stretched LZ 120. The airship was not merely a means of keeping the company afloat but to test the new technologies that could very well make trans-Atlantic air travel safe and reliable. Eckener himself flew ZR-3 out of Friedrichshafen on October 12, 1924, and despite some concerns about the airship’s maximum range, ZR-3 made the flight from Germany to the U.S. handily, despite running into a storm and encountering a headwind which slowed the ship down to 48 kilometers an hour. The airship flew over New York for several hours before proceeding to its shed at Lakehurst, New Jersey where it was met by a tremendous crowd. The ship would soon become the USS Los Angeles, and its success did more than save the company, it proved intercontinental air travel was more than achievable, it could be done safely and comfortably (eckener 27, 28).

The USS Los Angeles on parade over New York, joined by two US navy blimps, including the aluminum clad ZMC-2. (imgur)

ZR-3 also proved to be somewhat of a political litmus test. In the early Weimar period, its politics were especially volatile and Eckener had to brave these winds in order to accomplish anything. Whereas Count Zeppelin played the Imperial Court, Eckener faced liberals, conservatives, and political extremists of almost every variety. He did exceedingly well. The Zeppelin itself, a symbol of ‘the good old days’, played well with conservatives, liberals were satisfied with his ability to reinvent and grow the company in hard times, and the company’s large industrial workforce and generous benefits saw him receive congratulations from socialists and some communists. In terms of the far-right, he ranged from disinterest to outright hostility. Among the Nazis there was little interest in airships in general. Herman Goering, one of the movement’s leaders and former ace fighter pilot, saw airships as quaint and dated, with most in the party sharing his sentiments. Some members of even more extremist organizations claimed Eckener and Zeppelin had sold Germany out by giving ZR-3 to the US. Ultranationalists would go on to accuse the company of being controlled by a Jewish cabal and Eckener himself was the target of a young man with a rifle who had sworn to kill him, who was subsequently arrested (Rose 232). Eventually, some nationalists would be satisfied by Zeppelin’s all German operation and the ZR3 “controversy” would be left in the past. Despite this, the work at Zeppelin would proceed apace, especially as the German economy stabilized in the mid 20’s and many of the most dangerous fringe political groups had burnt out or had fallen out of public view, if only for the time being.

With a more or less stable political footing, and as the US Navy began to work their new airship into service, Dr. Eckener planned the next major step for Zeppelin.

The Graf

Eckener wanted an airship to build on the promise ZR-3 showed in its cross Atlantic outing. However, a roadblock appeared between Eckener and his new airliner, he hadn’t the money. The start-up capital to build and operate a new airship amounted to some 7 million marks, and to try and reach this figure he would attempt to repeat the miracle of Echterdingen. The press campaign began in July of 1925, and through donations and the sale of memorabilia, he was only able to amass 2.5 million marks, suitable enough for only the ship’s construction and nothing more. In short, the average German was far less secure in their finances, while the affluent noble class, once patrons of the old count, were gone (Rose 249). To make matters worse, airplanes had made significant strides in both safety and passenger capacity. Gone were the temperamental and fragile canvas and wooden biplanes, now in their place were solid plywood marvels like the Fokker F.VII and the all metal Junkers F.13, which rapidly took over intercity air travel during the mid 20’s.

Graf Zeppelin undergoing skinning in the Friedrichshafen hangar. (Zeppelin GMBH)

Regardless, Eckener pressed on, and between 1925 and 26 he gave nearly a hundred lectures on a press circuit which bolstered fundraising efforts. Once it was clear appeals to the public had reached their limit, he would make a personal request to President Paul Hindenburg, which brought a state contribution of 2 million more marks. The last of the money was found in selling assets from Zeppelin’s subsidiary companies (Eckener30, Rose 287). With the funds in hand, the design work was finalized with the new airship being what was, more or less, a larger derivative of LZ 126 with some cutting edge features. However, the new LZ 127 would not be the largest and most efficient airship the company was capable of building, but rather it was a proof of concept that would show that commercial, oceanic air travel was possible. While they had the funds for a new airship, they were still restricted by the size of their hangar at Friedrichshafen, which would prevent them from building airships much larger than the wartime X-Class for years to come.

Graf Zeppelin’s lounge prepared for dining service. (Yurigagarin-flickr)

By early 1927, LZ 127’s design work had been completed, and while built along the same lines as ZR3, it was fully furnished for passenger comfort. The combined gondola would contain the control and navigation facilities, along with the passengers rooms and amenities. The fore section contained the control room, a radio room, and a navigation room for use for the crew, and behind it was the kitchen, dining room and lounge, and passenger quarters. At the rear of the gondola were the stairs which led to the main crew quarters which contained mostly the same amenities, though with none of the fineries which existed below. The style of the passenger quarters evoked that of the famous and luxurious American Pullman railcars, though with some clever features. The passenger berths served dual purposes, by day they were lounges where passengers could take meals and relax in private, and by night they could be converted to a two bunk cabin.

Each 2 person passenger berth could be converted into a lounge during the day. (Zeppelin GMBH)

While LZ-127 could mostly be described as an enlarged version of the company’s previous airship, it did feature a number of innovations. Chief among these were its new Maybach VL2 engines, which in addition to producing a respectable 530PS, were multifuel engines that could run on either gasoline or Blaugas. The former was a fuel specially designed for airship use, as it possessed a density very close to air and could be stored in its own gas cells below the hydrogen. This enabled them to cut weight and conserve ballast hydrogen over long trips, as unlike gasoline, when the Blaugas was burned it did not significantly alter the weight of the airship and did not require the venting of hydrogen to regain equilibrium. Gasoline usage was kept to a minimum and would typically be reserved for takeoffs. Despite much of the design being brought over from a previous project, the airship was far better equipped for long flights. Its 37 tons of Blaugas could provide fuel for around 100 hours of flight, with a similar weight of gasoline providing only 67 hours (Rose 289).

Graf Zeppelin was built to the widest diameter that could be accommodated by the wartime hangar at Friedrichshafen. (Zeppelin GMBH)

The airship was completed in early July 1928, it being brought into service on the 8th and named Graf Zeppelin, in honor of the late Count. Shortly after a series of shorter test flights, Eckener arranged for a thirty six hour endurance flight across Germany on September 18th. The original course took the ship over Leipzig, Dresden and Berlin, before proceeding to Hamburg to practice oceanic navigation at night over the North Sea. However, the low cloud cover would have prevented the public from seeing the airship along that route and so they diverted to Frankfurt and Mainz before heading on to Cologne and Dusseldorf before reaching the North Sea via the Rhine valley. As was the case so many years ago, they were met by massive crowds as they passed these cities before finally heading out to sea. On the next day their course home took them over Hamburg, Kiel, and Berlin before they proceeded south back to Friedrichshafen (Eckener 32). However, not all were pleased. During further flights in October, French authorities protested the flight over the politically contentious Rhine territories, and subsequently provided directions for the use of airships over their own territory, forcing LZ 127 to fly at night and away from any military installations. The airship’s flight over southern England would also prove rather unsettling to those living there as it brought up unpleasant memories, and the airship would only rarely travel to Britain thereafter (Rose 289).

Graf Zeppelin over Berlin’s city palace during its first overflight of the city. (Bundesarchive)

These early flights would prove extremely promising, the only major issues which arose were political in nature, and the airship itself proved superb. Naturally, Eckener pushed for a flight to Lakehurst, New Jersey.

To Lakehurst

Eckener was prepared to fulfill the promise long dreamed of since the invention of the balloon and kindled during DELAGs best years, he was going to prove air travel could deliver passengers anywhere across the world. 40 crewmen and 20 passengers were assembled for the flight, though few paid for their tickets as they were mostly there to drum up publicity. This included journalist Lady Drummond-Hay, who had come on behalf of the media mogul William Randolph Hearst, who had exclusive reporting rights in the US for the voyage. One of the four who did pay the small fortune of $3000 for a ticket was one Frederick Gilfillan, an American financier who had a plane crash and two shipwrecks under his belt (Rose 295). To add to the foreboding, the weather reports were bleak. Storms and strong winds pervaded most of the approach to New York and numerous older steamships were in distress, while more modern liners were reporting considerable delays to their arrival (Eckener 34).

Eckener took the airship out of Wilhelmshaven on October 11, 1928, opting for a longer, but hopefully calmer Southern approach. The other captains, Fleming and Schiller, agreed to take a course South to the Mediterranean via the Alps, then to Gibraltar, followed by the Azores, and finally proceeding across the Atlantic to the airfield at Lakehurst. This earliest section of the voyage proved the most enjoyable as passengers and crew overflew the scenic Northern Mediterranean with largely agreeable weather. This however, was not to last. As after they flew west off the Azores, they ran into a storm front, and in the midst of exchanging the deck crew for the most experienced members, the nose dipped. Pots and pans clattered to the floor, the breakfast table settings slid from the cloth, and thunder rang out. While the crew remained in control through the rough weather, the passengers were no less terrified (Eckener 39). However, more shockingly, the crew would discover a wide swath of fabric had been torn from the lower port elevator and stabilizing fin, and threatened to jam the controls. By the time this was recognized, the Graf Zeppelin was in the middle of the Atlantic and three days from US navy assistance. After Eckener reported the incident to the Navy, he dispatched a repair team, which included his own son, and informed the passengers of the situation.

The repair team luckily found the damage to be less threatening than they had worried, and that they would be able to reattach the third of fabric that had remained , while cutting away the fluttering edges. The repairmen wore safety tethers while they clung to the outside of the airship and endured the roughly 80 kilometer an hour slipstream as the ship bobbed up and down as the control crew compensated for the increase in weight brought on by the rain. The repair crew worked for around five hours until the ship could rely on the fin once more (Eckener 41).

The result of the storm damage. (Wikimedia)

While the ship was no longer in danger, the new problem became boredom and discomfort. Safety precautions prevented the kitchen from using its electric stoves, lukewarm coffee was served in glasses, as all the china cups had broken in the morning, and, perhaps most distressingly, the beer and wine had run out. The passengers, with the exception of Lady Drummond-Hay who brought plenty of warm clothes, learned just how chilly the Atlantic could get, as the airship had little insulation. Though, the passengers discomfort was eclipsed by the elation of the crowd that gathered to see the ship as it flew over Washington DC, Baltimore, and Philadelphia before it went on to New York. This would prove prudent, as it showed the public that despite the damage it had taken, it was in no danger and capable of traveling wherever its crew saw fit (Rose 299, Eckener 43).

The discomfort of many of the passengers was quickly overshadowed by the Graf Zeppelin’s arrival at Lakehurst. Some 150,000 people had traveled to Lakehurst, where they were policed only by some 76 marines, 50 sailors, and 40 state troopers. While Eckener received congratulations from President Hindenburg via telegram, he embarked on a number of press ventures and all manner of celebratory events in New York. All the while, he was kept informed of the repairs being made to the airship, which would take 12 days and delay their return to Freidrichshafen until October 28.

Graf Zeppelin often shared the Lakehurst hangar with the USS Los Angeles during its visits to New York. (Wikimedia)

In all, the trip was successful but with mixed results. On a financial basis, the trip was successful in that it was profitable going one way. The operating costs were judged at $54,000 one way, with cargo and passenger revenues bringing in roughly $70,000; beyond that were the press deals which saw Zeppelin receive some $83,000, though these were likely to be considerably reduced for a regular commercial route. Eckener would claim a profit of $100,000, which considering the one million plus price of the airship, meant long term profitability was feasible.

The performance of the airship in the press was seen as both groundbreaking, yet unimpressive. From Germany to the US, the cross Atlantic voyage took some 111 hours, which actually compared poorly to the world’s fastest ocean liner, RMS Mauretania, which managed the crossing in 107. However this would be dispelled when Graf Zeppelin made the return trip in better weather, without detours, and arrived 72 hours later (Rose 301). Passenger comforts too were an issue compared with the ocean liner, though with a larger liquor cabinet and a gramophone with an ample selection of records, things were markedly improved on subsequent voyages.

Chief of all were safety concerns, as despite the airship being capable of handling the storm and subsequent damage better than any plane, it was still extremely concerning to any serious customer base. There was however, one feat which could allay these concerns for good, a world tour. However with the winter fast approaching, such a trip would be put off until a more favorable season.

Egypt Bound

The Graf Zeppelin would fly twice across the Mediterranean, visiting many of its most ancient landmarks (bsmith2123)

While a world tour was not feasible for several more months, a trip eastward was planned to raise publicity and bring in much needed capital. To promote the airship, a number of high level government officials and members of the press were invited. The choice of location would be Eastern Mediterranean, and much like the pre-war DELAG flights, the emphasis was on sightseeing. A particularly frigid winter would delay the flight four weeks until March 21, 1929, whereafter the Graf Zeppelin flew to a more hospitable region. It made its way down the French Riviera, after which it passed over Corsica and Elba on its way to Italy.

As they over flew Rome, with its ancient and modern sights alike, they sent a telegram to the head of Italy, Benito Mussolini. “Filled with admiration as we look down on Eternal Rome with its timeless remembrance of a glorious past, and its lively activity as a flourishing modern metropolis, we respectfully send our greetings and our good wishes to the genius of this splendid city.” Eckener would derisively say that he wondered if Mussolini would believe himself to be the “genius” of the city. The response would read “Many thanks for your friendly greeting! I wish you a happy journey. Mussolini.” (Eckener 59). From Rome it was on to Napoli, then Eastward across the sea to the Isle of Crete. Their arrival in the Eastern Mediterranean came with the end of the chill that had followed them since their departure from Friedrichshaven. With the last of the coats coming off, the airship made its way to Tel Aviv, and on to Jerusalem with the ship spending the night above the Dead Sea.

Graf Zeppelin over Jerusalem. (The Atlantic)

Unfortunately, the Graf Zeppelin was denied passage over Egypt by the British Foreign Office. This was likely because they wished to be the first with their own airships, which in a few years time were to fly from England, to Egypt, and then on to India. Eckener would be forced to tell King Fuad of Egypt that the weather prevented any landing there. However in 1930, the Graf Zeppelin would repeat this flight and would carry aboard a number of distinguished Egyptian passengers who were flown over the Pyramids and north, over the coast to Palestine.

During the first flight however, the airship overflew the coasts before heading Northward to Greece. They reached Athens at 6 am, there flying over the ancient Acropolis and then on to Mount Olympus. The planned overflights of Romania and Istanbul were canceled after deep cloud cover was reported over much of the region, and thus they returned to Athens, to the enthusiasm of those who slept through the airship’s first visit. From there it was West to Corinth before making the return trip to Friedrichshaven. The route home was to be over the Dinaric Alps, on to Pressburg and Vienna, before heading west and home. Apart from some passes through narrow clearings, and a blizzard which came on as they passed over Vienna, the return trip was uneventful. In fact, Eckener himself was glad for the poor weather as he was able to impress upon his passengers the safety of the airship and its ability to handle the elements (Eckener 65).

The Egypt flight of 1929 would prove an incredible and undeniable success in comparison to the admittedly rough Atlantic voyage. In addition to the views of some of the most ancient sites across the region, there were no hiccups in regards to lapses in comfort or entertainment, as the ship passed over the less exciting spaces in the dead of night. Perhaps most importantly of all, the ship’s reliability shone through with no major mechanical issues being reported during the flight.

Around the World

A postcard illustrating the course of the world voyage. (The Atlantic)

With the sight seeing trip behind him, Eckener now had the ideal Autumn weather to prove once and for all the safety and reliability of his airships. The route was largely predetermined as the Graf Zeppelin would need to stop at suitably sized hangers to take on new supplies and undergo any serious maintenance should trouble arise. The ship could take on fuel, ballast, and hydrogen at a simple airship tether, but there it would also be at the mercy of the weather. As such, Graf Zeppelin would fly East over the Soviet Union and make a brief appearance in Moscow, then proceed to Kasumigaura Air Base near Tokyo, where a former wartime zeppelin shed had been transferred and rebuilt. From there it was across the Pacific to America, then to Lakehurst outside of New York, and home again after crossing the Atlantic. However, a wrinkle formed in this plan when William Randolph Hearst, who would pay $100,000 for exclusive media rights in the US and Britain, requested that Eckener begin the journey from Lakehurst. His deal covered a good amount of the overall operating expenses of the trip, valued at around $225,000, much of the sum being spent on shipping 25,003 cubic meters of blau gas to Tokyo. Eckener’s solution was simple: fly Graf Zeppelin to Lakehurst, announce the voyage to the English speaking press there, and then fly back to Friedrichshaven and announce it again to the German press. In doing so he placated Hearst and the more nationalist elements within his own country.

The rest of the expenses were largely paid through passenger and mail fares, though again, few bought their own tickets. The overwhelming majority of passengers were there on behalf of newspapers and a variety of media groups whose focus was on travel, though a single ticket could cost upwards of $2,500. Beyond that was a hefty $50,000 gained through German media deals, and a number of limited postage stamp sets which sold very well among collectors. Despite the record setting nature of the flight, it was to bring in some $40,000 after covering the considerable supply hurdles (Eckener 68, 69).

The Graf Zeppelin departed for Lakehurst on August 1, 1929. This was to be a fairly unremarkable flight save for its two special passengers, Sue, a baby gorilla, and Louis, a chimpanzee, who were being brought to their new home in the US. 95 hours later, they were in Lakehurst and the true voyage began (Rose 307). Graf Zeppelin would return to Friedrichshafen after an overflight of Paris. The trip so far would prove to have a markedly different atmosphere, as in addition to the card games, conversations, and the record player, which often hosted Eckener’s own collection of Beethoven and Mozart, the air was busy with the clatter of the reporter’s typewriters.

The airship would spend five days in Friedrichshafen preparing for the journey ahead, which was to cover some 20,116 kilometers. During the layover, a number of new passengers boarded including Commander Rosendahl of the US Navy, Professor Karlkin, a Soviet meteorologist, and Commander Fuiyoshi of the Imperial Japanese Navy who was accompanied by two members of the Japanese press. With a crew of 41, and 20 passengers on board, Graf Zeppelin flew east (Eckener 72, Robinson 272).

A post card depiction of Graf Zeppelin leaving Friedrichshafen after the second “start” of the voyage. (German Postal History-Stampcircuit)

Now prepared for the flight ahead, they departed and flew north east over East Prussia and the Baltics. The approach to Moscow saw the trip’s first real challenge, a low pressure area developed north of the Caspian sea and was moving north. This would create strong headwinds along the original route and could potentially strain the airship’s fuel supply, however if they chose to fly on a more northerly course they would have a favorable westerly wind. To the anger of the Soviet representative, and to the disappointment of the crowds that had gathered in Moscow, Graf Zeppelin flew north. Upon flying past the city of Perm and past the Ural mountains, it quickly became clear why they had to bypass Moscow. The immensity of the far east would have proven disastrous had they run out of fuel, it was a land which was mostly untouched and beyond human civilization. Regardless, the frustrated Soviet Press devoted a good deal of energy criticizing Eckener and leveling a number of conspiratorial allegations at his decision (Rose 309).

Beyond Central Russia was the expansive taiga which Eckener described, “Like an extraordinary, decorative carpet it blazed up at us in all its colors-green, yellow, blue, red, and orange-horribly beautiful when we thought we might have to land on this carpet and be trapped helpless and lost amid the swamps and countless criss-crossing little streams” (Eckener 75). Navigation here and across Northern Asia would prove difficult owing to the few landmarks, even the smallest villages were noted and used to chart a course, the smallest being made up of a number of tents. Among the many incredible sights on those northern latitudes were the distant villages of the Yakut people and the aurora borealis which shone over the horizon. As they neared edge of Siberia they visited the city of Yakutsk, where they dropped a wreath over the cemetery where German prisoners of the Great War were buried. From there they proceeded to the sea of Okhotsk where their trek through Siberia ended (Eckener 76-81).

Graf Zeppelin reached Hokkaido, Japan at dawn, and with good weather proceeded southward on to the Japanese mainland. The airship overflew Tokyo for some time and performed a series of maneuvers over Yokohama Harbor above the massed onlookers. When they came in to land at Kasumigaura, they were met by an immense crowd, as thousands had traveled across the country to see the airship.

A commemorative wood block print of the Zeppelin’s visit to Japan. (The Tokyo Files)

While the airship was impressive to crowds on both sides of the Atlantic, it hardly compared to the fanfare it received in Japan. While Graf Zeppelin shaved roughly two days off the next fastest way across the Atlantic, it had bridged Japan and Europe in less than four. The next fastest, and still rather exclusive method, the Trans-Siberian Railway, took two weeks. Otherwise, by fast steamer, it took nearly month. One local newspaper would claim the trip as one of mankind’s finest achievements, and the event would receive more column space than any other event in Japanese history until that point. Those aboard the airship would spend six days in Tokyo, with key members of the crew being invited to a series of events hosted by the Japanese government. Eckener and his officers would attend a lavish state banquet at Tokyo’s grandest hotel along with Japan’s highest ranking ministers and the Chief Admiral of the Navy. This however, could not compare to Eckener joining Emperor Hirohito for tea at the Imperial palace, after which he was presented with a pair of silver cups, a ceremonial sword and dagger, silk embroideries, and porcelain vases. The stay in Japan culminated in the entire crew having afternoon tea at the German embassy, with nearly every German in Japan being in attendance (Eckener 83, Robinson 273, Rose 309).

Graf Zeppelin over Yokohama Harbor. (Old Tokyo)

With their stay over, the crew prepared for the flight across the Pacific, though an accident in removing the airship from its hangar resulted in a delay until the following morning on August 23, 1929. The airship would depart minus its Soviet representative, and its Japanese contingent would be rotated out for Naval representatives Lt. Commander Ryunoske Kusaka, Major Shibata, and a reporter. The journey across the Pacific was fairly unremarkable apart from the distance traveled, and the views were often obscured by clouds and fog. Graf Zeppelin reached San Francisco on the early morning of August 25 where it was greeted by a number of airplanes and ships which had come out of the harbor to meet it. They then proceeded South to Los Angeles where it would land at Mines Field, the airship arrived late at night and went largely unseen, save for those who traveled to see it the following morning. Interestingly, the landing was made difficult due to a low altitude temperature inversion which required they valve off hydrogen as the denser layer of air otherwise prevented the ship from descending (Robinson 273). This effect is partially responsible for the region’s agreeable climate, and its smog.

The airship was greeted by half a dozen or so aviators as it reached San Francisco. (SADSM)

Unlike Tokyo, the stay would not be a long one, and after an evening with Mr. Hearst, whose massive mansion was in Los Angeles, the airship was preparing to leave again. However, upon trying to leave they were short on hydrogen and were forced to proceed at very low altitude with very little ballast, southward around the Rocky Mountains. Initially, it flew so low that it nearly struck power lines as it departed the airfield. From San Diego they traveled through New Mexico and, like the crew of the L 59 almost ten years earlier, experienced extreme updrafts which could drag the ship over a 300 meters upward. Eckener considered this the most difficult point in the journey, and he believed the region made traversing America by airship a serious gamble should one wish to travel from coast to coast. Apart from the Texas homesteader who took potshots at the airship, the flight proceeded smoothly after they reached El Paso, after which they swung north on a course that would take them over Kansas before reaching Chicago. While the airship was greeted by crowds wherever it went, Chicago’s excitement rivaled San Francisco’s as a handful of planes joined it in the air and massive crowds cluttered the roads and gathered in parks to see the airship overfly their city. On its departure, it visited the Goodyear-Zeppelin headquarters at Akron Ohio before making its way to New York to complete the journey (Eckener 90).

Chicago matched San Francisco’s excitement as Graf Zeppelin was greeted by planes, crowds, and caused massive traffic jams. (RareHistoricalPhotos)

The world flight was completed when Graf Zeppelin returned to the hangar at Lakehurst on August 27, 1929. While the airship had visited the city several times before, its reception on that date surpassed all the rest. On that day New Yorkers shredded more phone books for confetti than ever before, and after a massive reception at city hall, Eckener was invited to a meeting with President Hoover. There Hoover would tell him “I thought that the day of the great adventurers, like Columbus, Vasco de Gama, and Magellan, was in the past. Now such an adventurer is in my presence. I am happy, Dr. Eckener, that the American people have greeted you so warmly, and today would like to extend my personal good wishes for your enterprise.” (Eckener 93, 94)

Graf Zeppelin had made the 11,104 kilometers from Friedrichshafen to Tokyo in 102 hours, had crossed the 8851 of the Pacific in 79, and crossed the 5,632 of America in 52 (Rose 314). All of these were new records, and the lack of any major mishap would prove beyond a shadow of a doubt the safety and reliability of Eckener’s airship. With it completed it seemed it would be simple enough to begin a regular passenger service, though this was not to be. A massive stock market crash in the US in just a month’s time would spill over and leave the entire world economy in shambles, aviation in particular would be hit hard. All but the largest aircraft manufacturers were out of business, and what few fledging airlines existed were hit equally as hard.

The Desert and the Future

With the world in the grips of an economic catastrophe, Eckener had to redress his plans. Further airship construction would need to be put on hold and new streams of capital would need to be established. The admittedly lackluster successor to Graf Zeppelin, LZ 128, was canceled. With its cancellation also went the hope of a triangle airline scheme by which DELAG was to sell tickets which granted passengers access to North and South America and Germany. However, Graf Zeppelin completed a trial run with a complement of paying passengers and freight in 1930, flying from Friedrichshafen to Recife Brazil, and then to Lakehurst. It proved impractical, as the volatile and unpredictable North Atlantic weather made comfortable passenger travel impossible without a specially designed airship. While no additional triangle flights were conducted with Graf Zeppelin for some time, it made a profit of over $100,000. Owing to having only 11 passengers aboard, air mail and stamp sets made up most of the earnings (Rose 350).

Graf Zeppelin at Cardington field with the British airship R-100. (Fineart America)

In 1930 Graf Zeppelin made a number of publicity flights across the UK where tickets were offered for short sightseeing flights. By this point the British aversion to the Zeppelin had clearly run its course, perhaps this can be seen no clearer than when the Graf Zeppelin overflew Wembley Stadium during the FA Cup. Beyond this the Egyptian tour was revisited again, and with the tragic demise of the British Imperial Airship scheme after the crash of R-101, Zeppelins were allowed full reign over the region.

Graf Zeppelin would finally dispel Britain’s phobias during its English visit, here overflying Wembley Stadium during the FA cup. (Wolves)

In the meantime, Graf Zeppelin was hired out to complete a scientific survey of the North Pole in 1931. Without passenger fare, reporting rights and stamp sets would bring in most of the profits. Incredible concerns were raised over the Arctic weather and icing, which could disturb the airship’s equilibrium. Despite being seriously damaged by a hail storm, Graf Zeppelin completed the survey along with the Soviet icebreaker, Malygin.

Zeppelin survived these financially tumultuous years by very narrow margins, and oddly enough, was kept afloat by stamp collectors who drove up the price of the limited edition sets the company commissioned. However, in 1931, there were bright spots on the horizon for DELAG. Graf Zeppelin was to begin a regular international service to South America, and a new airship was being developed for cross Atlantic service.

Regular Service to South America

The airship landing field at Recife, Brazil. (picryl)

While regular triangle passenger flights between the three continents were well beyond the capabilities for Graf Zeppelin, it could chart a service to South America with ease. While the North Atlantic was frigid and temperamental, and had previously proven extremely uncomfortable for passengers, the tropical and relatively warm waters of the South were ideal. After the Arctic flight, three passenger flights to South America were conducted in the late summer and autumn of 1931. These early flights were fairly limited, after leaving Friedrichshafen they proceeded over Southern France, Spain, the South Atlantic, and arrived in Recife, Brazil where an airship mast allowed them to service their vessel. This sole mast and its fairly remote location required DELAG to partner with the German Condor Airline to service other major cities across South America (Robinson 279). In spite of this, these initial flights would prove so successful, that all publicity flights were terminated so that all efforts could be taken to focus on the South American line.

Graf Zeppelin’s groundbreaking South American trips were the first of their kind, and were refined over the coming years into a regularly scheduled route. (Hapag Lloyd)

The following year would see nine passenger flights, the last three of which saw the airship fly down to Rio de Janeiro in order to draw interest to build a hangar there. Beyond this the flights were improved in the choice of view. When the airship departed or returned to Europe, it often did so through the French Rhone Valley and over the Bay of Biscay, or it proceeded south over Spain and then to the Cape Verde Islands off of Africa. Occasionally, there were also scheduled stopovers in Barcelona and Seville, where the excellent weather often permitted the airship to remain outdoors for sometime (Robinson 280). While the 1931 flights were more or less experimental, those of the following year were routine, all of which sold out, and beyond ticket sales the revenue from freight and mail was not inconsiderable (Ecekener 115).

As successful as these flights were, they were overshadowed by events in Germany. The Nazis were gaining greater prominence, with the regime exerting an ever more dominating force over the country, though Zeppelin and DELAG remained independent for the moment. In the backdrop of such developments, Eckener was able to see that the Rio hangar was built. The year would see another nine trips, the last being a triangle flight that would take the airship to the 1933 Chicago World’s Fair.

By the summer of 1933, the aviation authorities in Germany required all registered aircraft to display the Nazi swastika. The Graf had swastikas painted on the port side of its vertical stabilizers, the other emblazoned with the older Imperial style flag. Displeased with having to carry the symbol, Eckener flew the airship around Chicago on a clockwise course which hid the swastikas from crowds. He was, however, unable to prevent it being photographed by circling planes, with the subsequent images being printed in newspapers images world wide. This would not be the first time he attempted to act against the new regime. Prior to this, he forbade the Nazis from holding events at the new massive hangar at Freidrichshafen (Rose 357, 364). These marked the first in a number of protests Eckener had against Nazi propaganda minister Josef Goebbels, who wished to use the Zeppelins to carry the flag of the new regime. Beyond this, Goebbels often took to chartering the airship for political events and publicity flights, much to the annoyance and displeasure of Eckener and many airship crewmen who hated the politics of the new regime and saw these “circus flights” as a waste of time.

In spite of the ongoing feud, DELAG continued to improve its services to South America. Graf Zeppelin flew twelve round trips to South America in 1934, the third flying as far as Buenos Aires where Eckener unsuccessfully tried to convince the Argentinian government to build an airship hangar. Buenos Aires was to be a major hub for DELAG, as it was hoped that they would be able to make sales amongst the sizable German enclave there. However this was not to be, and instead they bolstered their partnership with the Condor Airline which could fly the airship’s passengers from Rio de Janeiro by seaplane.

Graf Zeppelin’s overflight of Buenos Aires wasn’t enough to convince the Argentinian government to help finance an airship hangar there. (Wikimedia)

The political environment became more contentious during this time, as Goebbels’ propaganda ministry and Goering’s Air ministry began to feud over the airships. Both offices devoted large sums to the production of LZ 129 and chartered increasing usage of Graf Zeppelin. Despite his long standing personal disinterest in the airship, Herman Goering recognized it as an important and internationally recognized symbol of German aviation. A symbol which he knew improved the standing of his new office, in contrast with Goebbels ideological zeal. In any case, both men knew they could force Eckener’s cooperation through the resources they devoted to his company, despite what trouble he would occasionally cause them.

The year 1935 would continue to see a business boom for the Brazil route, and saw 16 round trip flights across the Atlantic. There was also considerable growth in passenger travel which peaked in that year at 720 with an additional 14,061 kilograms of freight carried, including some 900,000 letters (Eckener 116). In short, DELAG had pioneered the international airline just as it had in 1919 when it achieved regular air service with Bodensee. However, just as it had been in 1919, DELAG would be dissolved again.

Political Troubles and the End

LZ-129 Hindenburg comes in to land at the airship hangar outside of Rio De Janeiro, here the two airships alternated on the South American route until the loss of Hindenburg at Lakehurst. (Wikimedia)

Just as DELAG was honing its international air service, it was dissolved. Air Minister Goering would reorganize most German airlines, and he would visit this on DELAG on March 25, 1935. The new Deutsche Zeppelin Reederei (DZR), or German Zeppelin Shipping Company, would take its place, this new entity being state owned. In doing so, Goering would have final say on airship use, largely putting an end to the quiet feud with Goebbels.

With this change came a transfer of command, Eckener was replaced with Lehmann, of Great War fame. Lehmann was an able commander and fiercely nationalistic, which made him a far more palatable choice over the decidedly liberal and world trotting Eckener. The former became chairman of the Board of Directors and still held some influence, but his control over the airline and the Zeppelin company, which he still presided over, slackened. Eckener continued to work for the airline in order to ensure safe operations, and to do his best to keep the Nazis from becoming too intertwined with the business. Initially, he was successful, as LZ 129 entered service to become the second airship on the South American route, after he had first flown it to the United States. Its name too, Hindenburg, was chosen for its lack of ties to the new regime.

This state of affairs was not to last as the political tides grew more volatile. As a result of Ecekener’s open and continued complaints about Goebbels’ use of the airships, the Reichsminister would issue an order to remove all mention of Eckener in any future news publications. This would backfire spectacularly when President FDR assumed and looked forward to Eckener being the captain of the Hindenburg on its first Atlantic voyage to the United States. Rather than admit a blunder on the world stage, the publication moratorium was lifted temporarily, with Goering subsequently intervening between the two and meeting with Hitler to have the moratorium lifted entirely (Rose 393, 395). In any case, and in spite of his own convictions, Eckener’s work would continue to benefit the Nazis and he would continue to stay, and work in Germany.

The final straw came a year later in 1937, when Hindenburg caught fire over Lakehurst in the most infamous airship disaster. While accidents were common in air travel at this point, never had one so spectacular been caught on film and so publicized. In spite of DELAG never having lost a passenger in its decades of operation, passenger airship travel would end there. As a result of a flashy landing stunt to bring the airship in quickly, Captain Lehman overstressed one of the rear structural rings and snapped a bracing wire. The wire tore a hydrogen cell, and a static discharge ignited the air mixture near an aft ventilation shaft (Rose 440, Eckener 173). Following the accident, what interest the state and public had in the airships quickly dissipated, and Graf Zeppelin, after nearly ten years in the air, was decommissioned and later dismantled. Eckener himself would largely go into retirement, though on paper he remained a key figure at Zeppelin and some of its subsidiaries.

Conclusion

The Graf Zeppelin coming in to land at an airport in Basel, Switzerland. (TagesWoche)

The airships built by Count Zeppelin and the airlines which operated them can be said to be among the most groundbreaking endeavors in the history of aviation. In terms of long range aviation, many of their efforts would outpace their competitors for upwards of a decade. In regards to air travel, nearly every major milestone was achieved first using their airships. DELAG would be the first to pioneer passenger air travel, establish regular, scheduled transportation flights, and build the first transcontinental airline. While the passenger airship was dealt a fatal blow with the destruction of the Hindenburg under the DZR, ironically, few endeavors can claim to have done so much with so few injuries as the DELAG airline.

Advanced Technical Descriptions

LZ 1-1900

LZ 1 prepares to depart. (Zeppelin The Story of a Great Achievement)

LZ 1 had a symmetrical, cylindrical hull formed from 16 transverse, wire braced, rings composed of 24 polygons that were connected by 24 longitudinal beams. The rings were spaced 7.98 m apart, save for those around the two control gondolas, which were 4 meters apart. The hull was made from unalloyed aluminum, and thus was very soft and contributed to the airship’s structural issues. The beams, which comprised the hull were practically openwork I-beams and offered little resistance to compression or bending loads, resulting in the center hull bending downwards during its test flights. The hull measured in at a length of 128 m with a diameter of 11.74 m. (robinson 23)

There were 17 cylindrical hydrogen cells made from rubberized cotton. This material was composed of thin laminated sheets of lightweight cotton and rubber. Each cell was fitted with a relief valve, with 5 being fitted with control valves which allowed the crew to adjust for lift. The airship was covered in cotton treated with pegamoid to reduce drag and friction within the hull. Pegamoid was also used as a basic waterproofing material, its use was continued on Zeppelin’s until more suitable doping materials were employed during WWI.

The airship lacked large control surfaces, there being only a small pair of rudders above and below the nose, and a rear set which were connected to the sides of the hull. Pitch was changed by means of a 100 kg lead weight that was moved along the rail between the gondolas. This proved to be a very cumbersome and unreliable system, with the weight jamming on at least one occasion.

The diminutive Daimler engine and its bevel gear arrangement. (Wikimedia)

LZ 1 was controlled from two cars along the underside of the airship. These were both made of aluminum and designed to float in case of emergency. These were connected via metal piping which served to act as a walkway. Each carried a Daimler 4 cylinder engine which produced 14.2 horsepower at 680 rpm, with a weight of 385 kilograms. These each drove a pair of propellers on the upper hull above the cars, which they were connected to via bevel gears and shafts. These turned at a maximum RPM of 1200, considerably faster than the engine, in order to follow one of the Count’s theories. He would later find large diameter propellers operated at lower RPMs to be more efficient. The propellers themselves were made of simple flat sheets of aluminum and had four blades with a diameter of 1.22 meters(Robinson 24, Eckener 191).

 

 

Golden Years Airliners 1911-1914

LZ 10 Schwaben-1911

Crews gather to maneuver Schwaben after it lands (Stampcity)

LZ 10 Schwaben was the first specially designed airliner and almost fully divorced from the LZ 3 derivative airships. It was shorter and carried less hydrogen than the initial, and very unsuccessful Deutschland, but was far more efficient. The framework was made of a strengthened aluminum alloy, and used the tried and tested triangular girders that Dürr developed for airship use. The hull was 140.2 long and 14 m in diameter, containing 17 rubberized cotton hydrogen cells. This would be the last Zeppelin airship to use them, as they constituted a fire hazard and were responsible for the loss of this airship.

The Maybach C-X was the major success of the firm, which would go on to produce a number of specially designed aircraft engines. (Smithsonian)

Schwaben was powered exclusively by three 6 cylinder inline Maybach C-X engines, these being developed specifically for airship use. Each engine provided up to 145 horsepower and weighed 652kg. These water cooled motors had a displacement of 20.5L, and had a bore and stroke of 160 mm x 170 mm. Overall, they measured 129.5 x 182.9 x 86.4cm (Smithsonian). The forward engine was coupled to a pair of two bladed hard aluminum propellers, with the rear two being coupled to a pair of four bladed propellers. The rear propellers were a pair of two bladed propellers affixed to one another on the same drive shaft. They could propel the airship to a trial speed of 76.6 km/h.

The airship was controlled from the forward car which contained one of the three engines. Controls were improved as all the control surfaces had been moved aft, with the rudders and elevators being installed in a box like configuration at the rear of the airship. Ballast bags were installed fore and aft.

As with all DELAG airships, it did not lack for amenities and comforts. The passengers were seated in a gallery amidships. This compartment was composed of an outer frame sheet aluminum with inner wood supports and decorative framing. The inner compartment was covered in wood paneling that consisted of high layer plywood covered in mahogany sheeting. Pillars and decorative elements were decorated with mother of pearl inlays and the floors were carpeted. Ahead of the gallery was a small space for the attendant and an ice box with an accompanying liquor cabinet. To the rear of the gallery was a lavatory with a latrine made from aluminum fittings to save weight. The entire compartment was affixed to the hull with reinforced aluminum girders and cables.

LZ 11 Viktoria Luise & LZ 13 Hansa- 1911&1912

Viktoria Luise drops a line to its ground crew (this day in aviation).

These two airships were built roughly to the same specifications though Hansa was the heavier of the two owing to some minor difference in construction. These were very similar to the Schwaben in their overall layout, though they differed markedly in that they used goldbeater skins in place of rubberized cotton for their hydrogen cells. This material was a finely woven cotton fabric laminated with chemically treated sheets of cow intestine. It proved to be both lighter and could not accumulate a dangerous static charge and was used on all subsequent airships (Chollet 6).

The two also featured a crude cruciform tail section, from which the elevators and rudders hung. These were smaller than those mounted on Schwaben, but were no less effective. These evidently reduced drag considerably, as despite being 7.90 meters longer than Schwaben, both airships made for a trial speed of approximately 80 kilometers an hour. This added length allowed for an expansion of the passenger compartment (Stahl 66).

LZ 17 Sachsen-1913

Sachsen amidst a crowd of onlookers (Zeppelin GMBH)

This airship was built much to the same standards as the previous two but it was built to a shorter length and wider diameter. When designing previous airships, or in enlarging existing models, the common technique was simply to add a lengthening section. It was initially believed that nearly all drag was created by the frontal cross section, with very little being induced by the surface area of the rest of the vessel. The aim with Sachsen was to increase the volume of its gas cells, and thus its cargo capacity, while also keeping drag to a minimum. It was quite successful, but it entered service only a year before DELAG was dissolved at the start of the Great War, and thus had the shortest passenger service of these early airliners.

LZ 120 Bodensee-1919

Swedish soldiers help secure the landed airship. (Picryl)

Bodensee was built with a number of new design features which had become commonplace during the war. Chief of these were its teardrop shape, which cut down on drag while retaining a large hydrogen capacity; and its cruciform tail section, which improved stability and maneuverability. Despite having roughly the same hydrogen capacity as the Sachsen, built years earlier, Bodensee boasted a much higher top speed and lifting capacity, all while being considerably shorter.

The hull of the Bodensee was constructed of 17 sided rings of various dimensions, the largest being 18.6 meters in diameter. The hull was made of a more modern duralumin which made it far more resilient, and likely contributed to the long service life of the airship. Along the underside of the hull was a catwalk which gave the crew access to the engines and command gondola. Above the catwalk were the ship’s 11 hydrogen cells. The entire airship, including the gondola, was skinned in a doped cotton fabric which gave excellent weatherproofing.

The gondola itself was divided into a forward command section and a rear passenger section. The command section featured modern controls which had been commonplace for some years, most notably an electric control panel for hydrogen release. Its passenger space could be divided into five compartments seating four, with one VIP cabin in the front who paid double fare. Six more seats could be, and often were, fitted if the partitions were removed and the space was consolidated. As with the previous airliners, the cabin was well furnished with a fine wood paneling over the structural elements and specially made aluminum and leather chairs for the passengers. The decor was fairly subdued compared to the more lavish furnishings of past DELAG airships. Aft of the passenger compartment was a buffet staffed with an attendant who prepared meals with an electric hotplate. The last gondola compartment contained the restroom. (Robinson 258 Rose 196). Flights typically lasted seven or eight hours on its typical Friedrichshafen-Berlin Route. Owing to the short nature of the flights, the airship was crewed by only a dozen or so men.

The Maybach Mb IVa was the engine that powered the R-Class and all succeeding models of German military airships during the Great War. Surplus motors were used aboard the Bodensee and Nordstern. (Smithsonian)

The airship was propelled by four Maybach Mb IVa engines which were high altitude motors and were mass produced during the Great War for the R-Class, and later “height climber” Zeppelins. Owing to the lack of superchargers, they instead used incredibly high compression ratios, which meant they could not be run at high throttle below 6000ft. Some examples approached 300hp at high altitudes, but in the case of the low altitude Bodensee, they could be expected to top out at 245 hp under normal conditions. These were water cooled 23.1L inline 6’s with a bore and stroke of 165 mm and 180 mm, and a weight of 417.8 kg (Smithsonian, Robinson 258). Two motors were mounted in their own individual cars on each side of the hull, with a rear, centerline car containing two motors, side by side, and were geared to the same propeller. These were geared to a wooden 5.2 meter propeller with a reverse gear that could be used slow and maneuver the airship as it came in to land. Each engine car had a skeletal aluminum frame that was fabric skinned. The engineers worked in the cars to adjust their output, with commands being telegraphed from the control room, and to maintain them throughout long flights. In most cases this amounted to supplying them with more oil. The engines could propel Bodensee up to 132km/h, making it the fastest airship thus built. They also made it considerably overpowered and the crew had to be wary of oversteering when the engines were running near their highest output. The ship was later lengthened to extend its range and help compensate for this issue.

LZ 127 Graf Zeppelin 1928

An internal schematic of Graf Zeppelin. (Zepplinweltfahrten)

Graf Zeppelin was the largest and most advanced airship to serve with DELAG, with most of its features being tested and tried aboard the ZR 3. Graf Zeppelin’s hull was built to the restrictions of its hangar in Friedrichshafen with the 236.6m long and 30.5m airship having the familiar teardrop shape of its predecessors. Its structure was conventional, though made use of improved duraluminium and had built up sections around the gondola and the struts supporting the engine cars. The hull included two catwalks, one along the bottom, to give access to the engines, crew quarters, and gondola; and a center catwalk which gave access to the gas cells and the exterior of the airship should repairs need to be made. There were 17 hydrogen cells with a volume of about 85,000 cubic meters set above the fuel gas cells, which contained some 26,000 cubic meters of blau gas. Depending on the configuration of the airship, the combined gas capacity of hydrogen and fuel was normally 105,000 cubic meters (Robinson , Eckener 207). The use of blau gas meant a lower lifting gas capacity, but it freed up several tons of weight by eliminating the use of gasoline, and meant the airship needed less water ballast to offset the burning of a denser fuel source. The lower ballast requirements also made the airship easier to fly over long distances, as it meant the crew needed to make only minor adjustments to the airship’s trim and ballast. A small amount of liquid fuel was carried to bring the airship out of its airport, as burning it lightened the ship and aided in climbing without sacrificing any ballast water. The entire airship was skinned in treated fabric, its waterproofing treatment now containing aluminum, which gave the airship its iconic metallic sheen.

Graf Zeppelin’s Gondola (Zeppelinweltfahrten)

The lower hull contained the amenities for the crew, including the bunks, which were spaced out along the lower corridor, their restrooms, and a small lounge space where they rested and took their meals. The gondola itself was divided among the forward control rooms, and rear passenger quarters. The forwardmost was the control room, followed by a navigation room, the radio room, and kitchen. Control of the airship was managed through similar, but improved means compared to the LZ 120. The elevator controls in particular were improved by the use of a boost motor to make the difficult and physically straining job of the elevator man easier. A fully automatic gyro for rudder control was also installed, but often went unused as it was felt its impulses were too heavy and clumsy, in comparison to hand control from an experienced helmsman. Landing was done without the use of either system but was aided by the use of bubble pointers geared to both controls which accurately displayed the inclination of the airship relative to the inputs of its controllers ( ONI Lt. Cmdr. Kenworthy 3). In practice, both systems were typically only used when controllers were changing course against the wind. Navigation aboard the ship was often done through dead reckoning and star sighting, though it was also capable of radio direction-finding as well. A powerful 3 million candlepower searchlight was mounted aft of the passenger section which enabled altitude checks and drift readings in the dead of night (ONI Fulton 3,4). These systems were powered by a pair of auxiliary power units which took their fuel from the Blaugas reserves.

Heinrich Kubis, worked at some of the most fashionable hotels in Europe before becoming the world’s first flight attendant on the Schwaben. Pictured here setting a table in the Graf Zeppelin during its later years. (Wikimedia)

The kitchen was well stocked and the cook and his assistant prepared meals through the use of electrical stoves. Food was served on the airline’s own signature dishes and cutlery. There were ten two-passenger cabins, a pair of washrooms, and a lounge area that could be rearranged for dining or leisure. The original decor evoked the luxury of Pullman railcars, though the traditional, and fairly dated, wallpaper was later replaced with a coat of white paint to give the airship a more nautical feel. Passengers were less than thrilled over the fairly confined nature of their quarters and the lounge, though the annoyance of not being able to smoke was the chief complaint. After the first several voyages, the airship began to stock a larger liquor cabinet, impromptu tours of the airship were given, and a gramophone, which often played Eckener’s own extensive collection of Beethoven and Mozart, was brought aboard. Smoking however, was never allowed and the lack of insulation required passengers wear coats in cold weather.

The heavy duty, dual fuel Maybach VL-2 (Smithsonian)

Graf Zeppelin was propelled by five Maybach VL-2 motors, these being multifuel 33.3L V-12s which could run off gasoline or Blau Gas. The VL-2 was a specialized engine designed to run for long periods and to be easy to repair in flight by airship engineers. Each engine produced up to 570 hp at 1,600 RPM and weighed 1,148 kg. They had a bore and stroke of 140 mm and 180 mm. These were water cooled engines, with their radiators being at the front of the engine car where a pair of shutters controlled air flow. They were all geared to propellers via planetary 2:1 reduction gears, and like Bodensee, were reversible. They were initially all geared to two bladed wooden propellers, though all but the lower gondola would be fitted with larger four bladed 3.4 meter propellers. The lower car retained the shorter propeller as it would have otherwise run into ground clearance issues. The engines also had the benefit of a silica absorber which reduced moisture exposure and allowed them to reclaim fresh water, which proved very useful as the airship frequently crossed oceans (LT. Cmdr. TGW 3). These engines overall proved very reliable for their day, though on occasion they would encounter minor breakdowns which required a brief stoppage of all engines to fix it. They could propel the airship as fast as 128km/h, though the airship typically traveled at 112km/h which was ideal for fuel economy.

A sketch by artist Theo Matejko of one of Graf Zeppelin’s crew berths, these were spaced out along the lower catwalk. The crew lounge was above and behind the gondola. (Wikimedia)

For any considerably long voyage, a crew numbering at least thirty was required, and for regular passenger service, some 40 crewmen were aboard. On a flight from Germany to Pernambuco, Brazil on October 9, 1932, Graf Zeppelin was commanded and flown by the following: 1 commanding officer, 3 watch officers, 3 junior officers, 1 chief engineer, 1 assistant engineer officer, 1 leading engine man, 15 engine men, 2 electricians, 3 riggers, 3 radio men, 3 rudder men, 3 elevator men, and 3 stewards, these being a flight attendant and the two cooks. The longest watches belonged to the watch officers, the radiomen and riggers, and the leading engineering officers who all had a watch of four hours. Every crewman had their own bunk by the time of the regular South America flights (ONI Lt. Cmdr. T.G.W 1,2)

Graf Zeppelin’s control room, prior to the installation of instruments. (Zeppelin GMBH)

Specification:

Illustrations:

LZ-1 was the first airship built by Zeppelin and the only one that wasn’t designed by Durr. It flew quite well during its test flights but failed to attract buyers, it did however bring Eckener aboard the airship project.
LZ 13 Hansa was named for the medieval Hanseatic league of Baltic merchants and entered service with DELAG in 1912. The airship would later be based in Potsdam.
Bodensee was the first airliner to run on a strictly maintained schedule, as apart from the pre-war service, its aim was purely transportation and not sight seeing. Its time serving with DELAG was short, though it spent many years in Italian service under the name Esperia.

 

Where Bodensee set the standard for reliable service, the Graf Zeppelin set every major milestone in international air travel. Often flown under the captaincy of Dr. Eckener himself, the airship flew to many far off destinations from Tokyo to Rio De Janeiro.

 

Gallery

Personalities

Count Ferdinand Von Zeppelin was the foremost innovator of airship design for nearly 15 years. Stubborn, but generous, the Count remained unperturbed by setbacks that could have otherwise ended everything, and persevered to lead the world in airship piloting and development. He remained in nominal control of the company until around the start of the Great War, when his old-fashioned ways of managing the business caused friction within the new modern corporate structure of the company, with the Count subsequently entering semi-retirement. Pictured here wearing the Imperial Yacht club cap he took to wearing during flights. (Zeppelin GMBH)
Dr. Ludwig Dürr was the engineering genius behind nearly every airship the company built. Involved in redesigning the LZ 1, Dürr headed nearly every design team up to the Hindenburg and the second Graf Zeppelin. While many initially found the humorless engineer odd to work alongside, Dürr was accommodating to the newcomers to the company, who brought with them new techniques and theories in aeronautics. A homebody and an eccentric, Dürr rarely left Southern Germany, but his work circled the globe. (Zeppelin GMBH)
Entering the Zeppelin enterprise as a publicist, Dr. Hugo Eckener would become a pilot during DELAG’s first years, and would lead the firm following the end of the Great War. Politically savvy and ambitious, he led the firm through its darkest days and made DELAG a world renowned name once more. While Eckener never built his fleet of ocean striding airships, he would continuously break records and set nearly every major milestone when it came to modern passenger air travel. (Zeppelin GMBH)

Early Airships

Zeppelin and the Crown Prince, a patron of the Count. (Wikimedia)
Schwaben comes into land, making so little noise that the sheep used to keep the grass short are undisturbed. (SFO Museum)

 

A DELAG advertisement. (Smithsonian)
Viktoria Luise drawing a crowd. (Wikimedia)
Zeppelin’s airships had cemented themselves as a cultural fixture in Germany, here Schwaben is depicted in a game where players race to visit all of Europe’s largest cities. (Stadtmuseum Berlin)

 

Hansa’s passenger compartment without passengers or tables. (Wikimedia)
Prior to the Great War, DELAGs airships became a regular sight over many German cities.(Wikimedia)
Schwaben inside its hangar. SFO museum
Bodensee is managed by ground teams. (Pinterest)
Bodensee cruises over an airfield with a Zeppelin-Staaken bomber, built by a Zeppelin company subsidiary, and later used for advertising the Fletcher’s World magazine. (John Parker)
Bodensee’s hangar. (Wikimedia)
Bodensee comes in to land during its Swedish trip. (Wikimedia)

Graf Zeppelin

A ventral view of Graf Zeppelin. (Wikimedia)
Graf Zeppelin landed at the airship station at Mines Field, California. (SDASM)
The crew had access to much of the exterior of the airship via the ventilation shafts. On several occasions they enacted repairs on the protective fabric after harsh storms. (Life Magazine)
Graf Zeppelin is joined by a Junkers F.13 as it cruises over Berlin. (Bundesarchiv)

 

Despite its increased size, Graf Zeppelin could easily handle ground landings, just as all previous Zeppelin airliners made. (The Atlantic)

 

Graf Zeppelin over Berlin’s Tempelhof field. (Bundesarchiv)
While on the ground, LZ 127 was maneuvered about by ground teams. (Bundesarchiv)
The Chef and his assistant at work in Graf Zeppelin’s kitchen. (Bundesarchiv)

 

The dining service during one of the airship’s earlier voyages, the Pullman carriage inspired decor was later replaced with a nautical theme. (Atlas obscura)
The rudder control position aboard Graf Zeppelin. (Getty)
LZ 127 over the Sumida river. (Old tokyo)
Graf Zeppelin flies over Seville, Spain. It stopped several times at the city on its South American route. (SevillaInsolita)
One of Graf Zeppelin’s engine cars. This gives a good view of the canvas frame of the unit. (Zeppelin GMbH)
Graf Zeppelin cruises past Rio de Janeiro on one of its earlier South American excursions. (Wikimedia)
A view of the hydrogen cell free hull of Graf Zeppelin. A ballast bag hangs at the right. (Zeppelin GMbH)

Credits

  • Written by Henry H.
  • Edited by Ed Jackson & Henry H.
  • Illustrations by Ed Jackson

Sources

Primary:

Eckener, Hugo. My Zeppelins. Putnam & Co. Ltd, 1958.

Von Zeppelin, Ferdinand. Die Luftschiffahrt Und Die Modernen Luftfahrzeuge. Berlin: Springer-Verlag, 1909.

Capt. Chollet, L. Balloon Fabrics made of Goldbeater’s Skin. NACA, 1922.

Curtis, Thomas E. The Zeppelin Airship. Smithsonian Report for 1900. 1901.

Dr. Dürr, Ludwig. The American Airship ZR-3. Zeitschrift des Vereines Deutscher Ingenieure. May 31, 1924, Vol. 68, No. 22. 1924.

Fulton, G., J. L. Kenworthy, James L. Fisher, and Edwin F. Cochrane. “LZ 127 Graf Zeppelin: Flight Reports by US Navy Officers,” October 1933, November 1934.

Mills, George H, Meister Von F.W. LZ 127 Graf Zeppelin correspondence relating to George H. Mill’s flights. 1934.

Ebner, Hans. The Present Status of Airship Construction, Especially of Airship Framing Construction. Zeitschrift fur Flugtechnik und Motorluftschifftfahrt Vol. 24, Nos. 11 and 12, June 6 and June 28, 1933 Verlag von R. Oldenbourg, Munchen und Berlin. 1933.

Stahl, Friedrich. Rigid Airships. NACA Technical Memorandum, 1920-1921.

Munk, Max M. The Drag of Zeppelin Airships. NACA. 1923.

Maybach VL-2, V-12 Engine. National Air and Space Museum. A19350052000.

Maybach AZ, In-line 6 Engine. National Air and Space Museum. A19791399000.

Maybach MB IVa, In-line 6 Engine. National Air and Space Museum. A19710882000.

Secondary:

Rose, Alexander. Empires of the Sky. Random House. 2020. (Ebook).

Maiersperger, Walter P. Design Aspects of Zeppelin Operations from Case Histories. NACA. 1975.

Robinson, Douglas H. Giants in the Sky History of the Rigid Airship. Billing and Sons Ltd., London. 1973.

Vissering, Henry. Zeppelin The Story of a Great Achievement. Chicago. 1922.

Kaman SH-2F Seasprite

United States of America (1974)

Anti-Submarine & Utility Helicopter

190 total airframes built: 85 converted to SH-2F w/ 48 new airframes.

A SeaSprite takes on fuel aboard the Destroyer USS Briscoe. (National Archives)

Introduction

Kaman’s SH-2 proved an exceptional asset for the US Navy through the mid to late Cold War, serving a variety of roles across nearly the entirety of the surface fleet. Beginning its service as a multipurpose naval helicopter designed to ferry equipment and rescue downed fliers, the light helicopter soon played an even greater role as an anti-submarine aircraft. Replacing the outdated and clumsy DASH drone, the Seasprite incorporated cutting edge sensors to become a sub chaser that could fit on even the lightest modern frigates in the US Navy. Spanning the early sixties to the new millenium, the Seasprite served as an able light transport, search and rescue, and anti-submarine helicopter before finally being phased out by the UH-60 Seahawk.

Whirlybirds

Of all the world’s navies, that of the United States was the first to employ helicopters enmasse. While helicopters had undergone considerable development since the first usable designs had been conceived in the 1920s, they remained a clumsy novelty into the 1940s. This was until the Sikorski R-4 was developed. Igor Sikorski, born in the Kiev Governorate in the reign of Alexander II, was already an aviation legend before the Russian Civil War saw him emigrate to the United States in 1919. Having previously designed four engine biplane airliners in the Russian Empire, and several of the flying boats that saw Pan Am span half the globe, Sikorski was a name known for breaking new ground. His R-4 helicopter would build this reputation further. The greatest advantage the R-4 had over its foreign contemporaries, most notably the Focke-Anchleis 223, was its simplicity and ruggedness. The use of a main lifting rotor and anti-torque tail rotor would prove a far lighter, and more robust method of control than the transverse and intermeshing rotors that drove a number of contemporary types.


Igor Sikorskiy (right) aboard a test flight of his R-4 helicopter (wikimedia).

The R-4 reached the notice of the US armed forces through Commander William J. Kossler of the Coast Guard, after the officer had seen the XR-4 undergo a test flight in April 1942. Impressed, he invited fellow officer CDR W.A. Burton to see the helicopter. The report on the aircraft took note of its ability to conduct patrols at low speeds, and unlike US Navy airships, did not require a large hangar for storage. Initially skeptical, the Navy was later convinced of the aircraft’s anti-submarine and convoy surveillance properties. Limited production began in 1942 and testing was conducted through 1943 and ‘44, though its sub chasing capabilities were not pursued. Instead, the helicopter proved itself as an air rescue vehicle. Its first trial came on January 3, 1944, when it delivered vital blood plasma from New York City to Sandy Hook, New Jersey, through a violent storm, in order to treat sailors after a fire had sunk the destroyer USS Turner. In all, several dozen R-4s would be delivered to the Coast Guard and Navy, where they took part in a number of rescue missions across North America and the Pacific.

While the R-4 was still limited in its carrying capacity and presented pilots with challenging flight characteristics, it demonstrated the utility of helicopters to every branch of the US armed forces. Sikorski would capitalize on this over the coming decade with their heavy H-19 and H-34 helicopters. Entering service in the early fifties, these helicopters were all metal and equipped with heavy radial engines. In civilian and military service, they would prove exceptional, capable of airlifting cargo to otherwise unreachable areas. However, a new, revolutionary advancement would soon render them obsolete. In 1955, the French Allouette II became the first production helicopter to feature a geared gas turbine. The turbine provided a far better power to weight ratio than the radial engines, and it was compact, allowing it to be placed at the center of the helicopter and thus avoided the forward engine placement that made some earlier helicopters nose heavy. This engine also allowed the nimble Alloutte to possess a speed and range far beyond comparable piston engined models. From then on, it was clear that turbine power would be the future of helicopter design.

 

A Sikorsky ‘Choctaw’ helicopter hovers to recover astronaut Alan Shephard and a Mercury reentry capsule after the first manned US space flight. The addition of a powerful radial engine made these among the first successful heavy lift helicopters. (wikimedia)

In the US, the first experiments for this type of helicopter propulsion were pioneered by Charles Kaman’s aircraft company. The first successful experiment was achieved through combining the Boeing 502 turbine with his company’s K-225. Kaman, a former employee of Sikorsky, would develop this new helicopter along with his head designer, Anton Flettner, a German engineer who pioneered the use of intermeshing rotors. The experimental K-225 proved promising enough to warrant further development, and soon, the Kaman Aircraft company would produce a new utility helicopter along its lines. The firm’s HH-43 Huskie fire fighting and rescue helicopter fit the bill, and its later models were equipped with turboshaft engines in the late 50s.

 

However, the firm’s greatest success was soon to arrive, when the navy sent out a request for a new carrier-borne, lightweight helicopter.

Seasprite

The US Navy’s request for a light multipurpose and rescue helicopter was soon met with Kaman’s newest design, the Kaman Seasprite. The helicopter would settle the requirements, being capable of carrying up to 12 people, remaining compact and fuel efficient, and taking up little space aboard aircraft carriers. In the 1956 competition, Kaman’s design won handily and the next year saw a contract issued for procurement. The helicopter was the first Kaman design to feature a single main rotor, and in conjunction with the servo-flap rotor system, it was cutting edge, reliable, and possessed smooth flight characteristics.

The design, then named HU2K, first flew on July 2, 1959, and was introduced fully in December 1962. It proved to be robust with good handling, however, the single General Electric T58GE turbine left it fairly underpowered. This prevented it from taking on any new missions, but it was sufficient for the basic role it was designed for. These helicopters, later designated UH-2A and UH–2B, though largely identical, were produced until 1965, with a total of 142 airframes built.

A Kaman UH-2A/B flies alongside the USS Enterprise as a plane guard as it launches a Grumman E-2a Hawkeye. (wikimedia)

The Seasprites, supplied to utility helicopter squadrons, were distributed amongst US aircraft carriers and saw widespread use during the Vietnam War. There, they served largely as plane guards, where they took up a position alongside aircraft carriers when large scale air operations were underway. In case of an accident during take off or landing, the Seasprites would move in quickly to recover downed pilots. Search and rescue also fell under their purview, and alongside a number of other models, they pulled hundreds of airmen from the sea. As a fleet utility helicopter, they also flew ashore and between various vessels in order to transfer personnel and equipment. Medical evacuations were also among tasks these helicopters performed, moving injured personnel to ships with more substantial medical facilities. The small size and smooth controls of the Seasprite made landing on the basic helicopter facilities of most ships an easier affair compared to the bulkier Sikorsky Sea King. Its only drawback was the relatively little power offered by its small turbine engine. It could make for tricky takeoffs as the small helicopter was slow to climb.

In spite of it being underpowered, it proved to be a valuable asset to the fleet and was respected by its pilots. Naturally, the Navy wished for improved models. Kaman’s first move was to add a second turbine engine to the helicopter, the improved model being the UH-2C. As the production run had already been completed, the Navy sent Kaman the older A and B models back to the company in order to receive the upgrade. The C model was introduced in 1966, though now with its much higher speed and carrying capacity, it was soon deemed that the Seasprite was to take on a much wider scope of duties.

Sub Chaser

During the late sixties, the increased threat posed by ever more advanced models of submarines was of great concern to the US surface fleet. Even more concerning was a lack of long range anti-submarine weapons. While many ASW vessels did carry the ASROC missile, tipped with either a nuclear depth charge or a Mk 46 torpedo, there was some concern of submarines attacking from beyond the 6 to 8 mile range of this weapon. The existing long range anti-submarine weapon was the Gyrodyne DASH drone, a small drone helicopter capable of carrying depth charges and torpedoes. While it was compact, it was inflexible, and with no means of collecting additional data in the area of the suspected submarine, accuracy was very poor.

The UH-2D was an interim ASW model to test the helicopters ability to carry the equipment needed for the role. These are differentiated from the later 2F’s by their tail wheel being further out. This aircraft lacks the sonobuoy rack. (wikimedia)

This left most of the US Navy’s light surface forces, which often operated too far from the carrier to be covered by its airborne ASW umbrella, under threat from more modern submarines. The solution was found in the re-engined Seasprite. The new SH-2D represented the greatest change thus far, with the new aircraft sporting a chin mounted surface search radar, a rack to carry a Mk 46 lightweight torpedo, and a 15 chute sonobuoy rack. The small size of the helicopter would allow it to operate aboard some of the lightest frigates in the fleet, these being the Garcia-class.

The performance of the helicopter, and its ability to operate on nearly every major surface combatant, would see this mission expanded even further. Thus came the Light Airborne Multi-Purpose System, a fleet-wide program to equip most warships with helicopters in order to boost their anti-submarine and anti-surface capabilities. LAMPS I would place a now standardized SH-2F aboard nearly every frigate, destroyer, and cruiser in the fleet. In addition to the long standing utility missions, the helicopters were datalinked to their host ship to allow them to prosecute possible submarine contacts, provide long range surface surveillance, and allow for more effective over the horizon targeting of enemy surface threats.

The new SH-2F was largely the same as the proceeding UH-2D model, though it standardized the use of composite rotor blades which existed on some previous models, and its tail wheel was moved forward to enable it to better operate off of smaller ships. Some 85 Seasprites were converted to this type, and a further 48 were produced in the early 80s in order to cover a shortfall before the introduction of the SH-60B Seahawk. The new, standard LAMPS helicopter entered service in 1973.

LAMPS I

The LAMPS I program vastly increased the offensive and surveillance capabilities of participating vessels. This encompassed some half dozen ship classes ranging from the workhorse frigates of the fleet, such as the Knox and Oliver Hazard Perry, to the nuclear guided missile cruiser, Truxton. In the ASW mission, on detecting a suspected submarine, whether attacking or transiting, the ship would launch its SH-2F. Capable of using sensor data from the ship, the helicopter would move in and begin to deploy its sonobuoys, being either passive AN/SSQ-41’s or active AN/SSQ-47’s. The helicopter then relayed the sonobuoy data back to the ship for processing, and if the contact was found and classified, the helicopter would move in to attack with its Mk 46 torpedo. The onboard magnetic anomaly detector could also mark the position of a submarine if over flown by the helicopter. A ship equipped with ASROC could also join the helicopter in the attack, provided the target was in range. In the ASW role, the helicopter was a largely reactive measure, as it was unable to process its own sonobuoy data and lacked a dipping sonar, and thus required other platforms to detect the submarine first. This is not to say it lacked considerable offensive potential, as the powerful hull mounted sonar arrays aboard the Knox class frigates and Spruance class destroyers, and the OHP’s short range but highly sensitive sonar, were among the most advanced systems of their kind and could give early warning to submerged threats. The presence of the helicopter thus allowed ships to prosecute, classify, and engage submerged contacts that would otherwise be beyond the effective range of their sensors and weapons.

The Spruance class Destroyers were among the most capable anti-submarine warships used during the Cold War. With their advanced sonar systems and two helicopters, they could pose a serious threat to even the most modern nuclear submarines. (National Archives)

The Spruance class in particular could prove very dangerous to submarines at range thanks to its convergence zone sonar. The AN/SQS-53 could make use of the aforementioned phenomenon, and under ideal conditions, detect submarines at extreme ranges. These zones are where sounds are bounced off the seafloor or thermal layers into a concentrated area and are thus made dramatically louder. Convergence zones are exploited by all ASW vessels, though the specialized sonar aboard these ships allowed them to exploit sound propagated at distances far in excess of the norm. A Spruance class ship making use of a convergence zone could dispatch helicopters against submarines potentially dozens of miles away, making them among the most capable ASW vessels of the Cold War. In the absence of a convergence zone, it switched to a short to medium range mode. It shared this system with the Ticonderoga class guided missile cruiser, and the Kidd class destroyer, both of which used the same hull, however their role was air defense. These ships all transitioned to LAMPS III once it became available in the mid 1980s.

The LAMPS system featured most prominently in escort and screening vessels, namely the Knox and Oliver Hazard Perry (OHP) class frigates. The Knox class was an anti-submarine frigate with limited anti-surface capability that entered service in 1969, with 46 vessels being commissioned in all. These ships carried a single Seasprite and were armed with an ASROC launcher, which later received the capability to launch Harpoon anti-surface missiles. The OHP class carried no ASROC launcher, though they instead carried two helicopters. The last 26 of the class were LAMPS III ships and carried the heavier and more capable Sikorski Seahawk. In place of the ASROC launcher was a Mk 13 mod 4 launcher for Standard missiles and Harpoons. Both frigates carried hull sonar and towed arrays, the Knox possessing a larger hull array, and the OHP carrying a short range, high resolution hull sonar system, with a towed array being used for longer range surveillance. The difference in systems was due to the OHP being designed as a fast escort, and needed the capability to conduct passive sonar searches at speeds faster than a typical surface group. The resulting hull sonar system was thus highly sensitive, but had a decreased maximum effective range.

The Knox class was initially classified as a destroyer escort and later designated as a frigate. For mid to late Cold War vessels, they were very capable anti-submarine patrol vessels for their size with good anti-surface capabilities, featuring both a dual purpose ASROC-Harpoon launcher and a LAMPS I helicopter. (wikimedia)

In addition to the added anti-submarine mission, the Seasprite performed anti-surface support and anti-ship missile defense roles. In performing these missions, the Seasprite used its search radar to track and identify potentially hostile surface vessels. This allowed the host vessel to build a picture of enemy forces while putting itself in comparatively little direct danger. With this information, any LAMPS I vessel had early warning against potentially hostile surface vessels, and could also use the relayed information to more accurately fire Harpoon and Standard missiles over the horizon, without using its own radar and revealing itself. The extended surveillance range of a LAMPS vessel was pushed beyond 170 miles with the use of the Seasprite.

LAMPS I thoroughly improved the anti-submarine and anti-surface capabilities of much of the US fleet, with the Seasprite itself being an almost perfect off the shelf solution. While there were limitations, like the inability to perform an independent ASW search, the overall benefit of the ship not needing to prosecute sub surface contacts alone or having to reveal itself to perform a radar search in its patrol area was well worth the resources devoted to the Seasprite.

Late Career

Beyond ASW duties, Seasprites also allowed their host vessels to conduct surface surveillance over a much wider area. Here, an SH-2F identifies a natural gas carrier during Operation Desert Shield. (National archives)

By the end of the Cold War, the Seasprite had incorporated a number of improvements. These comprised a number of on board and weapon systems, perhaps most notably the introduction of the Mk 46 Mod 5, or NEARTIP, lightweight torpedo. The new model was designed to counter the latest advancements in Soviet nuclear submarine design, with the torpedo possessing an improved engine to make for a higher speed, an improved sonar transducer to increase the effective detection range of the weapon and add better countermeasure resistance, and had a new guidance and control group. The new weapon entered service in 1979, with kits being produced to convert old stocks to the new standard.

An improved model of the helicopter equipped with T700-GE-401 engines was also developed in 1985, though few were procured, as the Navy sought to increase supplies of the SH-60 Sea Hawk. Some of the improvements from the scaled back Super Seasprite did however make their way into the SH-2F. A number of LAMPS I helicopters during the mid 80s were equipped with FLIR pods for IR searches, IR jammers, chaff and flare dispensers, and an infrared sea mine detection system. Their service during the Gulf War saw them mostly perform ship to ship material and personnel transfers, mine detection, and medical evacuation roles, as Iraq possessed no submarines. Their primary mission in the theater was mine hunting duties, for which they used IR sensors in their search. They were only carried aboard lighter surface combatants during Operation Desert Storm, and weren’t present among the air wings of any of the aircraft carriers during the conflict.

After almost thirty years of service, the SH-2F was withdrawn along with most of the vessels that carried them. Its end was hastened by the withdrawal of the Knox class frigates from service and the sale of most of the short hull OHP frigates to foreign navies. The Navy would fully transition over to the Sikorsky Seahawk, a much larger and more powerful helicopter which carried two torpedoes, a dipping sonar, and incorporated sonobuoy processing capabilities.

Construction and Flight Characteristics

The Kaman SH-2F Seasprite was compact, and while conventional for a modern helicopter, was very advanced for its day. Its fuselage was watertight, possessed forward retractable landing gear, and was equipped with a variety of onboard sensors. While it could not perform waterlandings, its sealed canopy allowed it to float until the helicopter’s crew could be recovered. The pilot sat on the port side of the cockpit and the copilot/tactical coordinator, who operated the weapon systems, was seated starboard. The systems operator sat behind the pilot and operated the sonobuoy dispenser, the magnetic anomaly detector, and radar system. The systems operator lacked the equipment to process the sonobuoy data, which was instead processed aboard the LAMPS I host vessel and sent back via a data link.

An SH-2F instrument panel (wikimedia).

At the nose of the helicopter was the LN-66 surface search radar, designed for detecting both surface vessels and submarine snorkels. On the starboard pylon was the MAD streamer which worked in conjunction with an extendable antenna on the underside of the helicopter. This system worked by measuring the local strength of Earth’s magnetic field, and would spike if it encountered a large magnetic object, or in other words, a submerged submarine. Triggering a readable detection required the aircraft to over fly the contact and was thus typically used to pin the exact position of the submarine while preparing to attack after closing in during the sonobuoy search. The Seasprite carried a mix of AN/SSQ-41A passive and AN/SSQ-47B active sonar sonobuoys. The AN/SSQ-41A omni-directional passive sonobuoys operate at a depth of 60 ft for shallow searches and 300 ft for deep, and have a frequency range of 10 Hz to 20 kHz. Depending on their settings, they lasted between one to eight hours. The SSQ-47B active sonobuoy provided ranging information and operated at either 60 or 800 ft and possessed a maximum endurance of thirty minutes. Sonobuoy data was processed aboard the supporting ship and was used to localize submarine contacts that were otherwise too distant or quiet to be effectively tracked by the ship’s sensors alone. The information provided from the data link allowed the helicopter to detect, classify, and engage subsurface contacts in cooperation with the host vessel.

Re-detecting a submarine at longer ranges from the ship was difficult, as passive sonobuoys laid out in a large search pattern gave little chance of success. The best chances of re-detection on a lost contact was when it was near the surface, transiting, or maneuvering to avoid attacks from other vessels and aircraft. The standard procedure for sub chasing was to head down the azimuth of the ship’s sonar contact and to begin to lay a sonobuoy field to uncover its exact location.

The Systems operator station. To the left is the MAD readout, in the center is a scope for the surface search radar, and on the right is the (shuttered) sonobuoy display. (National archives)

The Seasprite was initially powered by a single General electric T58-GE-8F turboshaft before a second was installed on the UH-2C. These each produced up to 1,350 shp and allowed the SH-2F to travel at a top speed of 152 mph at sea level and allowed the small helicopter to carry up to 2000 lbs worth of equipment in the vertical replenishment role, with a maximum cargo hook capacity of 4000 lbs. To save fuel during emergencies, the helicopter could run on one engine on the way back to the ship. These engines were well regarded and considered very reliable.

The helicopter’s lift was provided by a 44 ft main rotor which used composite blades which were directed with servo operated flaps. These flaps are easily visible on the rotors, each having a wider chord than the rest of the blade. The flap is used to change the angle of attack of the rotor in flight and allows for smooth altitude adjustment. The anti-torque rotor at the rear of the helicopter had its blades increased from three to four going from the C to D model. The Seasprite handled well and was easy to perform a hover in, an important capability when it comes to search and rescue, and transfers to vessels without any landing areas. This was particularly important when landing on Knox class frigates, which both had significant air disturbance aft of the ship, and a very claustrophobic landing area.

In the air rescue role, the copilot would coordinate with divers and rescue crew. The cargo space of the helicopter could fit two stretchers or three seats. For water recovery of personnel, divers were carried aboard and recovered downed airmen through the use of a rescue hoist mounted on the starboard side of the helicopter. Mechanically driven, it had a capacity of 600 lbs.

Throughout the 1980’s, Seasprites were often equipped with a variety of new devices. This aircraft features two ALQ 144 IR jammers for missile defense, chaff and flare dispensers, and a FLIR imager. Crews also often removed the doors from these helicopters for faster entry and exit. (National Archives)

The Seasprite could carry a variety of unguided weapons, but rarely carried anything other than the Mk 46 torpedo, being either the Mod 0, or Mod 5 NEARTIP during the 1980s. On paper, the Seasprite could carry two torpedoes, but in practice, the second equipment position was taken up by an external fuel tank on ASW patrols. Both torpedo types measured 8.5 ft long with a diameter of 12.75 inches. The Mod 0 weighed 568 lbs, and both carried a 95 lb warhead. The Mod 0 possessed a maximum speed of 45 kts, with the NEARTIP being considerably faster. The NEARTIP provided better tracking of faster targets and better countermeasure rejection, having incorporated a new sonar transducer, control and guidance group, and a new engine which switched from solid propellant to liquid monopropellant. Prior to the introduction of the Mod 5, there was little hope for successful attacks against the fastest nuclear submarines of the 1970s. However, in confirming the location of a submarine, its position also became revealed to long range ASW aircraft which could make follow up attacks.

Other weapons included unguided 2.75 inch unguided rockets, and some rare, late examples possessed FLIR optics and could carry AGM-65 Maverick missiles. These weapons, however, were rarely ever carried. Later Seasprites carried a variety of countermeasures including an ALQ-144 tail mounted IR jammer and an ALE-39 flare and chaff dispenser. A considerable number of these helicopters were equipped with infrared jammers and flares during the 1980s.

Conclusion

An SH-2F is being used to evacuate a sailor who received severe burns, necessitating treatment off-vessel. (National Archive)

The Kaman Seasprite can be said to be among the most versatile aircraft ever operated by the US Navy. Entering service as a plane guard, the number of roles it served grew considerably over the years to encompass everything from medical evacuation, to anti-submarine duties. As the core of the LAMPS program for nearly 10 years, it gave US warships a boost in their offensive and defensive qualities against both surface and subsurface opponents.

Specification

SH-2F Seasprite Specification
Engine 2x General Electric T58-GE-8F
Output (maximum) 2300 SHP (2700 SHP)
Maximum Weight 12800 lbs
Empty Weight 8652 lbs
Range for Utility 234 N.MI
Radius of Action for Utility 111 N.MI
Endurance for Utility (ASW) [Ferry] 2 hours (1.9 hours) [2.8 hours]
Standard Armament 1 Mk 46 Mod 0/5 Lightweight torpedo
Crew Pilot, copilot/tactical coordinator, systems operator
Length of fuselage 40.5 ft
Width of fuselage 10 ft
Designation Sub type
HU2K/UH-2A Basic single engine utility helicopter
UH-2B Minor differences in avionics, later made identical to A model
UH-2C First two engine model
H-2 Army project, single engine
HH-2C Combat rescue model, 7.62 side door gun emplacements, M134 rotary gun turret. Two engines.
HH-2D Same as HH-2C but without armament. Used to test ASW equipment and loading. Two engines.
NUH-2C/D Test helicopter, two engines.
YSH-2E Testing helicopter for radar and ASW gear for canceled LAMPS II program
SH-2D Early ASW model
SH-2F Standard LAMPS I helicopter
SH-2G SH-2F with T700 turboshaft engines, improved avionics. Small production run.
Avionics Type
Surface Search Radar LN-66HP
IFF AN/APX-72
Transponder Computer KIT-1A/TSEC
UHF Radio Set AN/ARC-159
Secure Speech KY-28
ICS AN/AIC-14
TACAN AN/ARN-52
Doppler Radar AN/APN-182
Attitude Heading AN/ASN-50
NAV Computer AN/AYK-2
Plotting Board PT-492
UHF Direction Finder AN/ARA-25
OTPI R1047A/A
Radar Altimeter AN/AP-171
RAWS AN/APQ-107
Sonobuoy receiver AN/ARR-52
Acoustic Data Processor AN/ASA-26B
Data Link AN/ASK-22
Magnetic Anomaly Detector AN/ASQ-81
Radar Warning Receiver AN/ALR-54

Profile:

The SH-2F Seasprite was a simple, but excellent conversion of a proven airframe. Installed aboard much of the US surface fleet, it was a potent force multiplier.
During the mid 80’s, the Seasprite fleet received a number of improvements. These included the ALE-39 countermeasure dispenser, the AN/ALQ-144 IR jammer for use against heat seeking missiles, and later FLIR optics.

Gallery:

 

The Knox class’s helicopter facilities were quite claustrophobic, and precluded the use of a larger helicopter. (National Archive)
A forward view of a Seasprite aboard a Spruance class Destroyer. (National Archives)
Despite its small size, the Seasprite could carry a considerable sling load between vessels. (wikimedia).

A Knox class frigate during a visit to La Roche, France with its LAMPS helicopter on deck. Curiously, this ship’s Sea Sparrow launcher has been removed. (Wikimedia)
The colorful MAD streamer. (Wikimedia)
A Seasprite responds to a medical emergency aboard a freighter near a naval exercise. (National Archives)

A Seasprite flies as a plane guard alongside the USS America. An Essex class refit carrier sails in the background. (National Archives)
An SH-2F undergoes checks aboard the USS Iowa during the Northern Wedding naval exercise, 1986. (National Archives)

A small number of combat rescue helicopters were converted to recover airmen from potentially dangerous coastal areas. In practice, the nose mounted gun was typically not retained. (wikimedia)
With its rotors folded, the crew of the USS John Hancock prepare to stow their Seasprite. (National Archives)
A snapshot taken by a Seasprite: Soviet Submarine K-324 and frigate USS McCloy (Knox class) were engaged in mutual surveillance when the submarine’s screw became entangled in the frigate’s towed sonar array. The emergency was responded to by the Soviet oceanic survey ship SSW 506 and the American destroyer USS Peterson. The K-324 was a Victor III class nuclear submarine, this type being the most numerous modern Soviet nuclear submarine of the late Cold War.

Credits: 

  • Article written by Henry H.
  • Edited by  Stan L. and Henry H.
  • Ported by Henry H.
  • Illustrations by Godzilla

Sources

Primary:

Standard Aircraft Characteristics Navy Model SH-2F aircraft. NAVAIR 00-110AH2-8. Commander of the Naval Air systems Command. July 1974.

Andrews, Harold. Sea Sprite. Naval Aviation New 1983 (Feb).

Naval Aviation News 1985 (May-June)

Naval Aviation News 1983 (Jan-Feb & May-Aug)

Department of Defense authorization for appropriations for fiscal year 1982 : hearings before the Committee on Armed Services, United States Senate, Ninety-seventh Congress, first session, on S. 815.

Department of Defense appropriations for 1984 hearings before a subcommittee of the Committee on Appropriations, House of Representatives, Ninety-eighth Congress, first session / Subcommittee on the Department of Defense.

Department of Defense authorization for appropriations for fiscal year 1986 : hearings before the Committee on Armed Services, United States Senate, Ninety-ninth Congress, first session, on S. 674.

Department of Defense authorization for appropriations for fiscal year 1979 : hearings before the Committee on Armed Services, United States Senate, Ninety-fifth Congress, second session, on S. 2571

Department of Defense authorization for appropriations for fiscal year 1980 : hearings before the Committee on Armed Services, United States Senate, Ninety-sixth Congress, first session, on S. 428.

CDR Rausa Rosario. LAMPS MK III. Naval Aviation News 1980 (June).

Defense Department authorization and oversight hearings on H.R. 5167, Department of Defense authorization of appropriations for fiscal year 1985, and oversight of previously authorized programs before the Committee on Armed Services, House of Representatives, Ninety-eighth Congress, second session.

Secondary:

Polmar, Norman. Ships and Aircraft of the U.S. Fleet. Fifteenth Edition. US Naval Institute Press. 1993.

Sikorsky HNS-1 “Hoverfly”. United States Coast Guard.

Stuyvenberg, Luke. Helicopter Turboshafts. University of Colorado at Boulder, Department of Aerospace Engineering. 2015.

Garcia Class Frigate. NAVsource online.

Spitfire with DB 605A, “Messerspit”

Nazi flag Nazi Germany (1944)

Experimental Engine Testing Aircraft: 1 Converted Airframe

The enigmatic and misunderstood ‘Messerspit’ test aircraft lies at the center of a number of theories, its original purpose largely forgotten. (google.uk)

Introduction

Few aspects of the Second World War have been so misunderstood, misrepresented, and pushed into near mythology as the Luftwaffe’s test programs. Their discussion in less academic circles is dominated by rampant speculation from those who indulge in sensationalist historical stories. With respect to that, one might be surprised to find the bizarre photographs of a Spitfire Mk. VB with a Daimler Benz engine to be one of the few remaining genuine artifacts from an obscure Luftwaffe test program. With so little information publicly available, naturally, the odd plane’s origins, purpose, and performance have been drowned in a sea of speculation. However, while it is often erroneously claimed that the so-called ‘Messerspit’ was some bizarre attempt to combine the best aspects of the two planes, in reality, the aircraft was converted to settle a technical argument which had been raging in Luftwaffe research and development circles since 1942.

Engine Trouble

The history of fighter engine development is one of ceaseless improvement in power and weight which are largely achieved through improving methods of design, production, and the use of better materials. In the case of the Luftwaffe, it was not long until the chase for power was subsumed by the need to develop engines which could more reliably run on inferior materials. Following the end of the battle of Britain in the autumn of 1940, the Luftwaffe soon found itself short of several key materials necessary in building heat and corrosion resistant alloys, most notably nickel, tin, and, later, chromium and cobalt. Nearly all of these materials were available only in limited quantities across Europe, with tin, used in heavy duty piston bearings, being almost totally unavailable. This was further exacerbated by the transition to synthetic gasoline and lubricants, whose properties differed enough from their petroleum counterparts to cause trouble.

In order to cope with the restricted access to these materials, Sparrmetall economy alloys were introduced to ensure the aviation industry would have access to enough materials, albeit ones which would cause a slate of problems. The Bf 109E had nearly finished its production run before the transition to the new materials began and was soon being phased out by the new F model in late 1940, and there the trouble began. The new production DB 601N engines in these would make use of high octane C3 synthetic fuel. However, the engine was neither designed nor properly tested around this, and had instead been developed around the petroleum based C2. Beyond this, its nickel-poor, and thus corrosion prone exhaust valves, coupled with its more fragile piston and crank bearings, would soon create a web of issues that would take weeks to sort out.

A cut away of the troublesome DB 601N engine. (Flight Magazine)

The C3 fuel reacted chemically with the 109F’s rubber bag tank, and, if stored in the tank long enough, would ruin the anti-knock qualities of this fuel. When run on this degraded fuel, these engines soon suffered absolutely horrible mechanical problems, chief of which were violent vibrations which could thoroughly wreck them. The C3 fuel could also cling to the chamber walls after failing to thoroughly disperse through the fuel injectors, and then escape into the oil system. In most other aircraft, the fuel would simply boil away, but the Daimler Benz engine ran cooler than most, and thus the fuel would eventually dilute the oil until it failed to act effectively as a lubricant, resulting in increased wear or catastrophic engine failure in the worst cases.

Expecting the issue to be one of a mechanical nature, the fuel and bag were not seen as the obvious culprit. Rather, the engine mount, the air intake position, and the cooling system were suspect. This guess would be partially correct in the case of the intake. Eventually, they tracked the fuel degradation to the tank and adjusted the fuel injectors. The unreliable engine was then phased out for the DB 601E, which ran on the more common B4 fuel and was installed in the subsequent Bf 109F-3 and 4 models. Almost all Bf 109’s built after this point were run on this more common, lower performance fuel. Prior to this, the F series were restricted from running at emergency power and were at a considerable handicap in combat for much of 1941 and 42. Regardless of this impediment, many Luftwaffe fighter squadrons often found these their most successful years.

The Bf 109G initially provided no real advantage over its predecessor, and its unreliable engine would prove a particular liability in less than ideal settings, like this G-2 in Finland. (asisbiz)

Problems would resurface again when it came time to re-engine the 109 with the new DB 605A. Developed from the DB 601E, the new engine was to be a marked improvement, with its larger displacement, improved supercharger, and higher compression ratios promising a considerable increase in power. However, new material restrictions would sharply curtail the use of molybdenum, tungsten, and especially cobalt. Supplies of which practically dried up when Germany’s largest source in French North Africa had been lost after Operation Torch. Problems new and old emerged, the most egregious of which were exhaust valve failures, which were due to the low nickel content of the components, resulting in rapid corrosion and cracking. There were also lubrication failures, which were made worse after the switch was made from ball to sleeve bearings. The first Gustavs would enter service in early 1942, though they soon had their performance limited, off and on, to prevent engine failure rates from reaching unmanageable levels. As a result of these limitations, the Gustav was initially slower than the plane it was supposed to replace.

Problems were made even worse when the materials in the engines at Daimler Benz’s testing and development facilities did not match those on the production line, leading to considerable delays in destructive testing. It would eventually receive the improvements to allow it to use its emergency power setting, as exhaust valves were chrome plated and the oil scavenge system was improved, but it was clear that any major future increase in engine performance was only possible after a costly and extended development cycle. The DB 605A would finally be released from all restrictions in August of 1943, almost two years after the first Gustav left the factory.

The Blame Game

The DB 605’s flaws would be magnified in the light of a cascade of engine failures. The most publicized incident involved the loss of ace pilot Hans Marseille, who was lost in action after his engine caught fire and he died trying to escape his aircraft. (asisbiz)

Continued development of the Bf 109 was in a very precarious place, as performance improvements were expected without any major increases in engine power. These goals were largely unachievable for the time being, and thus most of those involved would try placing the fault with some other party when the unrealistic plans fell through. Willy Messerschmitt would place the blame with Daimler Benz, whose engines, he claimed, had cooling requirements that were too high, and thus required the use of larger, drag inducing radiators. In part, he was correct in that Daimler Benz’ engines ran cooler, though in doing so, he seems to have neglected issues with the plane’s radiators, which were supplied by other firms. The Bf 109 was fitted with radiators that operated under considerably lower pressures and temperatures than those used on Allied fighters, and were thus very robust, but less efficient. To his frustration, Messerschmitt was unable to increase the efficacy of the system without more efficient, high pressure radiators, which his suppliers were unable to provide.

In 1942, Messerschmitt began an increasingly adversarial correspondence with Fritz Nalinger of Daimler Benz on the state of his engines, and would request that he permit the engine to run at higher temperatures. In a letter sent in December of that year, he would draw a comparison between the ailing DB 605A and the powerful Merlin 61, then in service with the RAF. He placed particular emphasis on the higher operating temperatures and its use of radiators that were 55% smaller than those in service on the Bf 109. He would leave out that British aircraft designers were working with high pressure radiators which were far more efficient than those on his own aircraft.

At a conference with Göring at Carinhall in March of 1943, Messerschmitt would openly lay blame on Daimler Benz and Nalinger, largely reiterating the points from his correspondence. Nalinger would defend the firm by stating they had put their primary focus in designing the engine in reducing the frontal area and maintaining a high power to weight ratio, but he largely side stepped Messerschmitt’s Merlin 61 comparison by extolling the promise of the still in development DB 628. At the end of the meeting, it had become clear that both men would need to work against one another to defend their own reputations. By then, the Bf 109G had been flying for well over a year under strict engine power restrictions.

The Hybrid

To try and prove Messerschmitt wrong, Daimler Benz planned a simple and clear demonstration. They would install one of the firm’s engines in a Spitfire to show that the DB 605A did not require a large radiator to run. The Spitfire in question was EN830, a Mark Vb which had crash landed in the German occupied Jersey Islands in November of 1942. Its pilot, Lieutenant Bernard Scheidhauer, crash landed his plane after being struck by ground fire during a rhubarb raid over Northern France and a fuel leak prevented him from returning to Britain. After ditching his plane, Lieutenant Scheidhauer attempted to destroy the aircraft when it became clear that he was not on a British held channel island, however, there was insufficient fuel to burn the Spitfire. Scheidhauer was subsequently sent to Stalag Luft III, in Poland. He was among those murdered by the Gestapo after the legendary mass escape.

A standard Spitfire Mk Vb. (wikimedia)

The plane was subsequently taken in hand by the Luftwaffe, repaired, and used for trials at the Rechlin test center. It was later pulled from storage for Nallinger’s tests sometime in late 1943. The plane was re-engined with a DB 605A, though much of the rest of the aircraft was left as it was, save for the radio and armament, which were stripped out. All of the work was done at the Daimler Benz Untertürkheim factory in Stuttgart, after which it was delivered to the Luftwaffe for testing at the nearby airfield at Echterdingen. It was no simple effort to re-engine an aircraft, but it seemed to have been managed well. Testing began in the spring of 1944, with the report on the aircraft being finished May 10th.

The modified aircraft retained much of the same equipment, save for the weapons, which were removed. The avionics were likely all replaced with German alternatives. (Valengo)

The plane flew quite well and proved Nallinger right in that the DB 605A could work using a significantly smaller radiator area. It also made for an interesting comparison with the Bf 109’s radiators, as it was found that the high pressure model fitted to the Spitfire Mk V was 50% smaller but provided only 4% less cooling capacity. The tests also showed that the ‘Messerspit’ was about 25 km/h faster at lower altitudes than the original Spitfire Mk Vb thanks to its fluid coupling supercharger, which proved more efficient at low altitude. Between 4 and 6 km in altitude, the standard Mk V proved faster, before its single stage supercharger again proved less capable than the fluid coupling type on the DB 605A. The hybrid aircraft proved to be between 10 to 20 km/h slower than a Bf 109G-6 at all altitudes save for above 10.5 km, where the ‘Messerspit’ held a slightly higher speed and service ceiling. The experimental aircraft also out climbed the Bf 109 at all altitudes, however, this data is not particularly useful as the plane was unarmed and no ballast to account for its absence was installed.

Overall, the experiment produced mixed results, but proved Messerschmitt right. On one hand, the DB 605 ran effectively throughout the tests using radiators significantly smaller than were found on the Bf 109G. On the other, the type of high pressure radiator used on the Spitfire was not something that could be replicated, owing to numerous material and industrial limitations. In the end, it was Daimler Benz’s requirements that the DB 605 run cooler, and the inability of German radiator manufacturers to produce high temperature, high pressure models, that kept the Bf 109 from achieving greater performance. Following the end of the tests, the aircraft was placed in storage and was likely written off after an 8th Airforce bombing raid on the airfield at Etcherdingen on August 14, 1944.

The Ultimate Fighter?

Unfortunately, due to this unique aircraft’s strange appearance and obscurity, it has been at the center of a number of bizarre theories. Perhaps the most popular of these theories is that the Germans were trying to build a plane that blended the strengths of both the Spitfire and the Bf 109. Some go as far as to claim that the Germans had managed to build something superior to both. This first theory can immediately be written off. By early 1944, neither the Bf 109 nor the Spitfire were considered state of the art, or at the forefront of design in either country. They simply would not be considered an acceptable starting point for any new aircraft design.

However, beyond that, the ‘Messerspit’s’ performance was not particularly impressive for its day. In the official tests, it was compared to both an early Spitfire Mk Vb, which was thoroughly obsolete by the end of 1943, and a Bf 109G-6, which was mediocre by the standards of early 1944. Even then, it compared rather poorly with the G-6, possessing only a higher service ceiling while being considerably slower at almost all but the most extreme altitudes, where it held a slim advantage. To add to this, this low altitude performance gap with the Mk Vb only exists when its Merlin 45 engine is limited to +9 lbs of manifold pressure. When that engine was cleared to run at +16 lbs in November 1942, the Mk V exceeded the DB 605A powered ‘Messerspit’ at altitudes below 5.5 km in linear speed by a margin similar to the Bf 109G-6.

Spitfire Mk IX, Fw 190A-8, Bf 109G-6, P-51B (world war two photos, asisbiz, National Archives)
Aircraft (Manifold pressure) Top Speed at Sea level (km/h) Low blower/Speed (km/h) high blower/Speed (km/h) Maximum Output (hp)
Spitfire LF Mk IX Spring 1944 (18 lbs) 540 617 at 3.2km 655 at 6.7km 1720
Spitfire Mk VB Mid 1942 (9lbs) 460  N/A (single stage, single speed) 605  at 6.1km 1415
‘Messerspit’ Late Spring 1944 (1.42 ata) 488 N/A (variable speed SC) 610  at 6.5km 1454
Bf 109G-6 Mid 1943 (1.42 ata) 510 N/A (variable speed SC) 620 at 6.5km 1454
Bf 109G-6AS Early 1944 (1.42 ata) 506 N/A (variable speed SC) 653 at 8.3km 1415
Fw 190A-8 Early 1944 (1.42 ata)  558 578 at 1.5km 644 at 6.3km 1726
P-51B-15 w/ wing racks Early 1944 (67” Hg)  586  656 at 3.1km 685 at 7.2km 1720

*Values for the Spitfire Mk IX and Mustang indicate use with 100 Octane fuel and not high performance 150 octane, which became fairly common after mid-summer 1944 amongst the strategic fighter forces based in England. Likewise, Bf 109G-6 and Fw 190 performance does not reflect the use of MW50 or higher power clearances, respectively, as they were not in widespread use at the time of the tests. Unrelated, the P-51B-15 made for 627 km/h at 6.5 km with wing racks.

Compared to other contemporary frontline fighters of its day, its performance was far less impressive. The contemporary Spitfire Mk IX, with its Merlin 66 running at 18 lbs manifold pressure, outstripped the hybrid aircraft at all altitudes by a much wider margin than the Bf 109G-6. A further comparison with the Fw 190A-8 and P-51B-15 also demonstrates the continued extreme disparity in linear speed against more modern fighters. While the aircraft did demonstrate a very high climb rate, approximately 21 m/s at sea level (a Spitfire Mk IX made for 23 m/s), this can be explained by the lack of any weapons aboard. The Mk Vb was initially equipped with 2 Hispano 20 mm cannons and four .303 caliber Browning machine guns. The absence of these, and other pieces of equipment, reduced its weight by over 300 kg compared to the Mk Vb used in RAF and Luftwaffe performance trials. This resulting lightening of the aircraft, and the subsequent loss of drag with the removal of the protruding wing cannons, more than explains its high climb rate. The plane’s performance overall was very modest, and frankly did not compare well to any of its contemporaries. In the end, despite being a fusion of the Bf 109 and Spitfire, it compared rather poorly to either one.

Another theory presupposes that the plane was part of an effort to actually produce Spitfires for the Luftwaffe. The foundations for nearly all of these claims rest with an often misunderstood quote from the battle of Britain. When Reichsmarschall Herman Göring asked fighter group commander Adolf Galland if there was anything he needed, Galland responded “I should like an outfit of Spitfires for my squadron”. Galland would later clarify in his memoirs that he meant this rhetorically. In truth, he wanted a plane which could serve better as a bomber escort, something he felt the RAF’s Spitfires were better suited to, with their better visibility and low speed handling, than his own Bf 109’s, which he felt were more capable on offensive patrols. Beyond that, reverse engineering and then manufacturing an aircraft which was designed around the industrial standards and practices of another country was totally unfeasible. It also seems rather implausible that anyone would go to the trouble of building an airplane on the basis of an off hand remark made three years earlier.

Construction

A fore view of the experimental plane. (frankenplane)

The ‘Messerspit’ was built using the airframe of a later production Spitfire Mk Vb. The Mk V differed from earlier models in that it used a heavier engine mount to keep up with increases in output from new engines. It was otherwise much the same as the Mk I’s and II’s which preceded it. These planes were fairly innovative during the interwar period, being all-metal and using a semi-monocoque structure, though these features were soon made commonplace in the earliest days of the Second World War.

The fuselage contained the engine, behind which sat the fuel tank, the firewall, and then the cockpit. The tail boom was of a semi monocoque construction and contained the oxygen bottles, and radio. Aboard the ‘Messerspit’, the engine mount had to be reworked to accommodate a DB 605A, the fuel tank was likely changed to fit the new volume, and the instruments and most of the electronics were swapped for German versions. The radio appears to have been removed entirely. In all likelihood, Lt. Scheidhauer most likely smashed the instrument panel when he knew his plane was in enemy territory. Beyond that, they would have needed to convert the voltage to the German standard, and simply replacing all the equipment would have proven easier than modifying all of the existing components. There were also some instruments, like the DB 605’s RPM governor readout, that would not have had a British analogue.

The wings were elliptical with a large surface area, which granted the aircraft an excellent rate of climb and low wing loading. On the ‘Messerspit’, the inboard pair of 20 mm cannons and the outboard four .303 caliber Browning machine guns were removed and the ports were faired over. Most importantly, the radiator under the starboard wing was connected to the DB 605A engine’s oil and coolant lines. The wings were otherwise unchanged. Generally speaking, the better wheel brakes, greater visibility out the bubble canopy, and its wider wheel base would have likely made this a far more pleasant plane to fly than a Bf 109G.

A DB 605A mounted in a preserved Bf 109G-6 (wikimedia)

The engine was a Daimler Benz DB 605A, an inverted, 35.7 liter, V-12. The reason for it being inverted was to ensure the propeller shaft was as low as possible. This would enable a low mounted, centerline cannon to fire through its center without its recoil seriously jeopardizing the aircraft’s stability. They were able to achieve this using direct fuel injection, which was fairly common practice in German aviation by the start of the war, though rare elsewhere. The engine also possessed a high level of automation, which let the pilot manage the engine and most of its associated systems just through the throttle lever. These were essentially a series of linkages between components that adjusted one another as the pilot increased or decreased engine power. As such, it did not possess a true engine control unit, as was used in the BMW 801. Perhaps most impressively, the engine used a single stage, centrifugal supercharger which used a hydraulic coupling for variable transmission. The fluid coupling supercharger automatically adjusted itself barometrically, and was easily the most impressive feature of the engine, allowing it to smoothly adjust for boost as the plane climbed or descended. This allowed the aircraft to avoid the engine performance gaps between certain altitudes that were otherwise encountered with engine superchargers with multiple stages and fixed speed settings. These gaps were the result of running the supercharger at fixed, unnecessarily high speeds for a given altitude.

The engine used B4 87 octane aviation gasoline, as most of the C3 high performance stock was dedicated to squadrons flying Fw 190s. In comparison to the Merlin 45, which was originally in the Spitfire Mk.Vb, it produced 150 bhp more at sea level thanks to the fluid coupling supercharger, which saw lower pumping losses compared to the Merlin 45. The Merlin 45’s supercharger was geared to medium altitude use, and allowed the engine to outperform the DB 605A between approximately 4 and 6 km.

A DB605A mounted in a Bf 109G, cowling removed. (Norwegian air museum)

In spite of these innovative features, the engine’s output was fairly modest for its day. It produced up to 1475 PS, though this was only possible after several major modifications, such as replacing the exhaust valves for chrome plated sets and modifying the oil scavenge system by adding additional pumps and a centrifuge to improve flow and reduce foaming, respectively. Between 1942 and late 1943, the high power settings on almost all of these engines were disabled in order to keep failure rates manageable. The supercharger too would eventually lag behind its contemporaries, as despite its smoothness, its volume became a bottleneck. This was most apparent in comparison to the two-stage, intercooled models of the Rolls Royce Merlin engine. Some later models would mount an enlarged supercharger, taken from the larger DB 603, though the upgrade was not universal. Nearly all would be equipped with an anti-knock boost system in the form of MW50 in the weeks after the ‘Messerspit’s’ tests, which would boost output up to 1800 PS, though the corrosive mixture of methanol and water decreased the engine’s lifespan. Engines with the larger supercharger were designated DB 605AS, those with the boost system being DB 605M, and those with both were 605ASMs. These upgrades gave late war Bf 109’s a good degree of performance after nearly three years of mediocrity. Neither of these upgrades were present on the ‘Messerspit’.

The engine measured 101.1 × 71.9 × 174 cm, had a bore and stroke of 154 mm (6.1 in.) x 160 mm (6.3 in.), and weighed 745 kg (1,642 lb). The aircraft was equipped with the prop spinner from a Bf 109G, used the same supercharger scoop, and was likewise fitted with a two meter VDM propeller. The engine cowling of this aircraft seems to have been built for requirement.

Spitfire Mk V with DB 605A Specification
Engine  DB 605A
Engine Output 1475PS
Gross Weight 2740kg
Maximum speed at Sea Level 488 km/h
Maximum speed at Critical Altitude 610 km/h
Max climb rate at sea level 21 m/s
Max climb rate at FTH at ~6.5km 11 m/s
Crew Pilot
Wingspan 11.23 m
Wing Area 22.5 m^2

Conclusion

Another view of the experiment (Aviationhumor)

In the end, the ‘Messerspit’ was built to serve a single, fairly mundane purpose. It was never meant to set records, achieve any kind of technical breakthrough, or somehow be an unbeatable synthesis of two planes that had already seen their day in the sun. Above all, it was never meant to see combat nor produce a plane that would. Its only battlefield would be a corporate one.

Illustration

The Spitfire Mk V mit DB 605A, better known as the “Messerspit”.

 

Sources:

Primary:

Bf 109G-2 Flugzeug Handbuch (Stand Juni 1942).Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. November 1942.

Bf 109G-4 Flugzeug Handbuch (Stand August 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. September 1943.

Bf 109G-2 Flugzeug Handbuch (Stand August 1943). Der Reichsminister der Luftfahrt und Oberbefehlshaber der Luftwaffe, Berlin. October 1943.

Daimler-Benz DB 605 Inverted V-12 Engine. National Air and Space Museum Collection. Inventory number: A19670086000.

Flugzeug Flugleistungen Me 109G-Baureihen. Messerschmitt AG Augsburg. August 1943.

Flugleistungen Normaljager Fw 190A-8. Focke-Wulf Flugzeugbau G.m.b.H. Abt. Flugmechanik.L. October 1944.

Horizontalgeschwindigkeit über der Flughöhe: Normaljäger Fw 190A-8. Focke-Wulf Flugzeugbau G.m.b.H. November 1943.

Leistungen Me 109G mit DB 605 AS. Messerschmitt AG. Augsburg. 22, January 1944.

P-51B-15-NA 43-24777 (Packard Merlin V-1650-7) Performance Tests on P-38J, P-47D and P-51B Airplanes Tested with 44-1 Fuel. (GRADE 104/150). 15 May, 1944.

Spitfire V Steigleitungen. Daimler Benz. Versuch Nr. 1018105428. Baumuster DB.605A. May 1944.

Spitfire Mk. VB W.3134 (Merlin 45) Brief Performance Trials. Aeroplane and Armament Experimental Establishment Boscombe Down. June 1941.

Spitfire Mk. VC AA.878 (Merlin 45) Climb, speed, and cooling tests at combat rating. Aeroplane and Armament Experimental Establishment Boscombe Down. 25 November, 1942.

Spitfire L.F. IX. RAF Aircraft Data Card, 2nd Issue. 28, October 1943. The performance of Spitfire IX aircraft fitted with high and low altitude versions of the intercooled Merlin engine. Aeroplane and Armament Experimental Establishment Boscombe Down. March 1943.

USAAF 8th Airforce Bombing Raid Records.


Secondary:

Scheidhauer, Bernard W.M. Traces of War.

Douglas, Calum E. Secret Horsepower Race: Second World War Fighter Aircraft Engine Development on the Western Front. TEMPEST, 2020.

C. Douglass, personal communication, November 25, 2022.

Price, Alfred. The Spitfire Story. Silverdale Books. 2nd Edition, 2002.

Radinger, W. & Otto W. Messerschmitt Bf 109F-K Development Testing Production. Schiffer Publishing. 1999.

Spitfire EN 830. Lostaircraft.com

Galland, Adolf. The First and the Last. Bantam. 1979.

 

Credits

  • Article written by Henry H.
  • Edited by Stan L. and Henry H.
  • Ported by Henry H.
  • Illustrations by Godzilla

 

North American P-51B Mustang

sweden flag USA (1943)
Fighter Aircraft – 3,738 Built

 

A P-51B undergoes testing at a Lockheed reassembly plant in Liverpool, UK. December 1943. [National Archives]
Initially developed to provide an export alternative to the P-40 for France and the UK, North American’s P-51 would prove to be a superb aircraft that would rank among the most decisive weapons of the Second World War. With its streamlined airframe and highly efficient cooling system, the aircraft would reach new heights when equipped with the far more advanced Packard Merlin engine. Though its early years would prove troublesome, it would solve long standing issues regarding the lack of long range bomber escorts, and achieve a level of performance beyond its Axis contemporaries.

Interwar Fighter Developments

The Merlin powered P-51’s share the distinction of being among the most successful fighter aircraft ever developed, but also having one of the convoluted development paths of any mass production fighter. While the aircraft would make its first flights in 1943, it had its roots in the late interwar period where many of the technologies it incorporated were first established.

US interwar fighter development saw rapid technical advancement, but a comparatively small build up of planes. Here an XP-40 undergoes wind tunnel testing, the design would go through a number of changes that would result in the P-40. [This day in Aviation]
The general environment of interwar fighter development for the US Army Air Corps was one of high theoretical advancement, but comparatively slow practical development. While major milestones were made in regards airframe and powerplant design, there was considerably less urgency to develop and mass produce fighters for use by the Air Corps. This was mostly a result of an isolationist foreign policy, which limited availible resources, and to a lesser degree, a desire within the Air Corps to focus on bomber procurement. While the development of new fighters was limited, the Air Corps had great freedom in procuring aircraft for testing purposes. While funding was still limited, they were allowed to procure up to 14 examples of an aircraft through their budget before they would need to petition Congress for additional funding. While a large build up of the Air Corps during this period was a financial and political impossibility, it would prove sufficient for exploring aircraft design and development. This environment would exist into the late 1930’s as the political situations in both Europe and Asia destabilized, and subsequently, the order was given to continue the development of the XP-38, XP-39, and XP-40 into new fighters for use with the Air Corps (Ethell 9).

While these aircraft were being prepared for service, vital new developments were being made in regards to airframe design. At the National Advisory Committee for Aeronautics (NACA) offices at Langley field, efforts had been made to produce airfoils which could achieve laminar flow. In short, this effect is characterized by minimal disruptions to the airflow of the surfaces of the wings and adjoining fuselage. In the context of fighter aircraft, this allowed for a much lower drag coefficient, which would permit better acceleration and would lessen the instability encountered at higher Mach numbers. They would achieve this by June of 1938 when an airfoil displayed laminar flow characteristics in wind tunnel tests (Ethell 10).

Europe Ablaze

The escalation to and the outbreak of hostilities in Europe would completely dispense with the interwar malaise and saw the US begin a massive arms build up. The most notable shift in policy was President Franklin Delano Roosevelt’s call for 50,000 aircraft in January of 1940. The resulting surge of orders would end up leaving most US aircraft manufacturers at capacity, and though they would satisfy domestic demand, the fulfillment of export orders was not a priority. This represented a serious issue facing the Allies in Europe. At the outbreak of the war, the French and British air forces were still largely in the process of expanding and modernizing. While they both possessed examples of modern fighter aircraft, such as the Dewoitine D.520 and Supermarine Spitfire Mk.I’s respectively, they also employed a large number of outdated aircraft in comparison to the better equipped German Luftwaffe. The expedient solution to this problem seemed to be to purchase aircraft abroad, and the US was by far the best source.

To this end British and French interests were served by the British Purchasing Commission. While they had decided on the ideal candidate being the Curtis-Wright P-40, they found the at-capacity firm unwilling to compromise its contracts to the US Army. They were soon negotiating with other firms for P-40’s which would be manufactured under license, and by 1940 had placed as many orders as they could. It was clear to all parties involved that any of the larger firms that were involved in US rearmament would be unable to deliver any sizable number of aircraft to the Allies. In January of 1940, Oliver Echols, in charge of Air Corps procurement, would suggest to the Purchasing Commission to approach a manufacturer that lacked any major contracts involved with US rearmament (Ethell 10).

This suggestion would see the British Purchasing commission returning to older offers from firms that they had turned down the previous year. The most important of these would be North American Aviation. North American had earlier proposed to build P-40’s under license for the Allies, though the offer was given little consideration (Ethell 10). They were likely turned down over their relative inexperience in the field of fighter aircraft, having previously built advanced trainers, like the AT-6 Texan, and the crude NA-50 and NA-68 export fighters. In spite of this, and finding few options among other US aircraft manufacturers, the British Purchasing commission would once again approach North American. This time however, North American was given the option to either produce license-built P-40’s, or instead to design a new aircraft with the aid of research data acquired from Curtiss-Wright on the XP-46 fighter prototype. NAA’s small, but enthusiastic team would choose the latter, and prepared to design a new fighter built around the Alison V-1710 engine.

Enter North American

North American’s greatest claim to fame before the Mustang was the AT-6, arguably the best advanced trainer of its day. [Wikimedia]
By the standard’s of most US industries of the time, North American Aircraft was a fledgling company, though one with great promise. It was originally formed as a holding company in 1929 to purchase stock in other aviation concerns, and was later incorporated under General Motors’ General Aviation branch. As a holding company, North American would gather a considerable amount of resources in these early years, of particular note was the firm’s acquisition of Fokker. In 1934, as a result of new regulations on air mail carriers, General Motors was required to divest itself of North American, which then became an independent firm. Thereafter, North American incorporated its parent company, General Aviation, and continued under the direction of its president James H. ‘Dutch’ Kindelberger (O’Leary 9). He would subsequently take the company west in 1936 where they would open a new facility at Mines Field, California. Prior to the war they would develop the O-47 reconnaissance and observation aircraft, which had begun under General Aviation, and the AT-6 advanced trainer, which was among the most successful designs of its type. They would also produce a set of unsuccessful export fighters which were altogether unimpressive. With this in mind it’s understandable North American was initially passed over, they were in fact, inexperienced in fighter development and their only real foray into that field was a disappointment. However, when the British Purchasing commission returned to the company in 1940, they found the firm more than ready to meet their needs. Their contract was worked out for 400 planes at a price no higher than $40,000 dollars a unit, and spare parts in the amount of 20% of the value of the aircraft.

The first step in developing the new fighter was purchasing the most recent data on fighter design from Curtiss-Wright’s XP-40 and XP-46 prototypes, and acquiring the new breakthrough aerofoil designs recently developed under NACA (Ethell 10, 11). This information was made available to the design team headed by Edgar Schmued, a German born aeronautical engineer who had previously been a GM field service manager for their Brazil branch. The work soon began on a new fighter under the designation NA-50B, later changed to NA-73, under a common and straightforward design strategy. Schmued would work to build a plane that would excel by incorporating all of the most recent developments in fighter design to produce an aircraft that was both cutting edge, yet conventional (Douglas 252). The Curtiss-Wright prototypes were a starting point that was quickly surpassed, with engineer and aerodynamicist Ed Horkey considering the prototypes too dated for use on the new project, and the data was discarded (Forsyth 13). This came as somewhat of a blow considering they were forced to pay about $50,000 for the test data. The same cannot be said for the data acquired from NACA.

Edgar Schmued would join North American through its parent company’s acquisition of Fokker. He would lead the team responsible for designing the Mustang which would be developed continuously through the Second World War. [alchetron]
Horkey would come across NACA’s research through a confidential release for American industrial use, and was convinced that it would make an excellent addition to the new fighter’s design. NAA would send a representative to collect the data from NACA at Langley Field, and they would go on to receive minor technical support. While the design did not possess true laminar flow characteristics, it did drastically reduce drag and improve the performance of the aircraft (Ethell 11). Further streamlining was achieved through the mounting of a low drag, centerline radiator which incorporated the work of British scientist, Dr. F.W. Meredith. This divergent-convergent duct was capable of using the heat ejected by the radiator to actually produce thrust and offset some of the speed loss incurred by drag incurred by the radiator’s air scoop (Douglas 252).

 

Great care was taken to build the prototype in good time. The NA-73X, would make use of a number of components from North American’s AT-6 trainer, including its landing gear, hydraulics, and electrical systems. Remarkably, the construction of the prototype was completed on the 102nd day of the project, but it would have to wait another 20 days for its Allison V-1710-39/F3R engine (Marshall & Ford 94). The supply of Allison engines at the time was constrained, and resulted in the project having to delay its deliveries to the British. Despite this, the fast pace of the program, and the fall of France would see the British order another 320 aircraft before the prototype even flew. With the program approaching testing, the British were awaiting the results and readying their own test pilots to become acquainted with the new plane. The prototype was first flown by American test pilot Vance Breese on the 20th of October, 1940. It would go on to make several more test flights before having to be repaired after an accident with test pilot Paul Balfour. The accident was a result of pilot error, who failed to switch over from an empty fuel tank, and as such the incident did not reflect poorly on the design itself (Marshall & Ford 151). As the sleek new fighter was taking shape, the British Purchasing Commission would notify NAA that the aircraft’s RAF designation was to be the ‘Mustang’ in a communique sent in December 1940 (O’Leary 24).

This prototype NA-73 was delivered to the US Air Corps for testing, though they would not place orders for Mustangs until a later date. [This day in aviation]
Among the last modifications to the NA-73 regarded its armament, fuel capacity, and reinforcement of its wings. Several proposals for its armament were considered, but for the British Mustang they installed a pair of .50 caliber guns in the nose cowling with another two .30 caliber guns in each wing. With these last additions made, the British soon received several of the new aircraft, which now bore the more familiar title of Mustang. The first, AG345, would be put through tests to find any issues from the transition from the NA-73. Several issues arose over the stiffness in the ailerons, power surges in dives, and overheating. These were subsequently addressed, though more drastic changes were needed in the case of the engine, which required installing a new carburetor scoop, and altering the scoop for the radiator (Marshall & Ford 165). The culmination of these new changes would result in the finalized Mustang Mk.I, and a second development prototype, NA-83.

While the aircraft’s development was proceeding at a rapid pace for the British, the USAAC would show very little initial interest in the Mustang. The aircraft the USAAC had dubbed the XP-51 was largely overshadowed by other developments and comparatively little effort was made to conduct exhaustive tests on the XP-51 prototypes at Wright Field to correct their faults. Their interest in the aircraft would be piqued only after the U.S. entrance into the second World War.

Mustang Mk. I

In British service the Mustang would take a different developmental path than what was proceeding in the United States. While the British were receiving their Mustang fighter aircraft, the US had been forced to develop the aircraft into a dive bomber, the A-36, as funds for fighter development had been expended for 1942. In the case of the RAF, the Mustang Mk. I went into service as soon as was practicable and saw their first squadrons, numbers 161 and 613, receive supplies of the new aircraft in April of 1942. They would first be employed as reconnaissance aircraft before later taking on more dangerous work during Operation Jubilee in which they undertook offensive recon sorties over the raid area in Dieppe, France. Beyond this they would be subsequently used to fly nuisance raids and fighter sweeps across the low countries. Its long range, high speed, and effective armament were used to great effect over these areas as they harassed rail and road communications, while also remaining quite capable against enemy fighters wherever they were encountered (Ethell 24, 25). Even by this early mark, the once uncertain contract they signed with North American had already paid off.

It was during this period that the aircraft’s faults and strengths would make themselves evident. The nose mounted guns were troublesome and complicated maintenance; they were often removed from operational planes and were eliminated from the succeeding models of the aircraft. The radiator still presented teething issues, as under certain conditions the oil could freeze over and would fail to circulate, and eventually cause the radiator to boil over. Visibility too would become an issue, as the canopy frame of the cockpit severely restricted the pilot’s view. However despite its faults, the plane was fast, possessing good acceleration and a high top speed that made it capable of outrunning all fighters in the theater at sea level (Ethell 24).

The Mustang Mk.I would prove an exceptional fighter with the RAF, if at first, a little rough around the edges. [wikimedia]
While the radiator issues would be addressed and a new bubble canopy was developed, another, more serious drawback of the design would require far more resources to address. The Allison engines that the early Mustangs were equipped with were considerably lacking when it came to high altitude performance due to their single stage, single speed superchargers. While the aircraft received good marks for its low altitude performance from pilots in the RAF, above the 15,000ft the Allison V-1710 suffered considerable power loss. Though this was by no means surprising, it represented an area where performance could be significantly improved. At higher altitudes the aircraft was outpaced by both contemporary models of the Fw 190 and Bf 109. At low altitudes, it was made somewhat redundant by the RAF’s new Hawker Typhoon, which both flew faster at low altitudes and was better armed. It wasn’t long until the idea arose to fit the Mustang with an engine possessing better high altitude performance, a combination that might well produce an exceptional fighter that was as capable at high altitude as it was down low (Douglas 253).

The first major step toward this came on April 29, 1942, when Wing Commander Ian Campbell-Orde invited one of Rolls Royce’s test pilots, Ronald W. Harker, to test the new aircraft. Harker was impressed by its performance and he believed that if the aircraft was fitted with the new Merlin 61, it would be able to outpace a similarly equipped Spitfire by a considerable margin (Marshall & Ford 215). The Merlin 61 was the obvious choice for many reasons, chief of which was its two stage, two speed supercharger which stood to offer the plane exceptional high altitude performance. To this end, a Mustang Mk.I was provided to Rolls Royce at Hucknall to undergo the necessary modifications. By the beginning of June 1942, the British had correctly projected that the Mustang’s top speed would be increased to 430mph at an altitude of 25,000ft, which was roughly twice as fast as the Allison powered Mustang at that altitude (Douglas 254). When the test aircraft was complete the results were quite impressive, as during a fly off between a Spitfire Mk. IX and a Mustang, both fitted with Merlin 61’s, the Mustang quickly outpaced the Spitfire.

Across the Atlantic, a parallel development began underway after a study of the Mustang’s combat debut with the RAF. The new United States Army Air Force, no longer constrained by funding, rushed to acquire supplies of the Mustang, and sought to re-engine the fighter to improve its high altitude performance. To this end, two P-51’s were set aside for conversion. By the early half of the Summer of 1942, both British and American Mustang experiments were underway. While the Mustang was previously seen as a side project which was never a wholly American or British effort, it was by then extremely clear that the design had tremendous potential and the development of which was of immense importance to the Allies.

Shoeing the Mustang

Orders for various Mustang types for the USAAF would begin in 1942, including this P-51 armed with four Hispano 20mm cannons. These orders were quickly overshadowed by developments to get the Packard engine into the aircraft. [Wikimedia]
Re-engining the Mustang was by no means an easy task, as the Merlin was considerably heavier than the Allison and required a larger cooling system. To achieve this, the radiator was reworked, with the oil cooler moved apart from the radiator matrix to a forward position, and the ducting of the entire scoop assembly being redesigned. Earlier aerodynamic and buffeting issues caused by the radiator intake were also resolved by moving the scoop out of the boundary layer under the fuselage. The resulting set up would also achieve the earlier described Meredith effect, which produced thrust that offset the drag caused by the scoop (Marshal & Ford 97, 219). Additionally, the carburetor’s intake duct was moved beneath the nose which also necessitated lowering the wing to accommodate the lower cowl.

In addition to higher cooling requirements, the new Merlin engine weighed 350lbs more than the Allison and would mount a larger, heavier propeller, which would represent a significant shift in weight. To compensate, 61lbs of ballast was added, the primary fuselage longerons were strengthened, and the wings were strengthened and moved lower and forward. These changes would also help to compensate for the stronger vortex generated by the propeller and the greater forces generated by the improved ailerons (Marshall & Ford 219). The new engine and the subsequent operations would also result in some yaw instability. Adding a fin ahead of the horizontal stabilizer seemed an adequate solution, but it would not be undertaken until far later.

While the testing for most of these modifications was done through a variety of converted air frames, the prototype that brought them all together was the XP-51B, which first flew on October 1, 1942. The importance placed on this aircraft was considerable, as several months prior, a large order for 1200 P-51A’s was placed by the US government on the provision that their production could be switched for P-51B’s, given advanced notice (Marshall & Ford 230).

The first of two XP-51B’s would be ready in October of 1942, however, a long and difficult development process would delay serial production until the summer of the following year.[Thisdayinaviation]
The XP-51B would prove promising but it was troubled by radiator issues which would remain with the aircraft through January of 1943. These were tracked down to a chemical reaction which was found to be degrading the coolant tubes, and was resolved by a lacquer liner. There were also air flow issues within the radiator, which were solved through moving its aftercooler core to improve airflow through the scoop. The prototype’s last major issue was the tendency for its air scoop to produce loud, and worrying, vibrations at high speed. Resolving the problem once again required them to change the geometry of the scoop (Marshall & Ford 258, 311). This was solved by the aforementioned modification that moved it out of the boundary layer below the wing, and further improved as the depth of the gutter was increased and the inlet size was reduced (Matthews 7).


Most of the issues with re-engining the P-51 involved its cooling systems and air scoop, which were revised several times. [NACA]
All of the production models of the Merlin powered P-51’s would fly with engines produced under license by Packard. It was a matter of good fortune that Packard was already engaged in the mass production of their version of the Merlin engine prior to the demand for the engine for the new Mustangs. Packard had built its first V-1650-1’s, a license built Merlin 28, in August of 1941 which were later destined for use in Canadian built Avro Lancasters, DeHavilland Mosquitos, and the updated Curtis Wright P-40F (Marshall & Ford 176). Changing production to suit the needs of the P-51B would however not be easy, and matters were made worse by a general strike at the main plant which, alongside slow development at Wright Field, made for considerable delays. Some of the supply issues would be addressed as the new Mustangs would receive the first priority in terms of supplies, superseding the P-40F and L, and denying its use on the P-38. However, beyond these were the predictable teething troubles, and combined with the less predictable hurdles, they saw widespread deployment of the P-51B delayed considerably. Packard would go on to supply North American with engines, however they would never fully be able to meet the massive demands of both the United States and Great Britain (Marshall & Ford 347).

My Kingdom for a Horse

While development on the Merlin powered P-51’s proceeded, the USAAF had formulated and launched a strategic bombing campaign dedicated to destroying industries vital to the German war effort. The theoretical foundations of this strategy had been set in the interwar era and were initially seen as a means to expand the Army Air Corps into a force with greater autonomy. Many early interwar theorists, such as Maj. Harold George, would describe a vague ‘economic web’ that could be destroyed and force an industrial and morale collapse, but in 1943 these theories were put to the test. The practical details of the campaign were laid out at the Allied conference at Casablanca. There a series of targets was decided upon, but later altered to a plan that favored targeting aircraft and submarine production, in addition to ball bearing plants (Overy 45, 305). However, the main concern for USAAF bombing operations was that thus far, all daylight strategic bombing campaigns had ended in failure after formations of unescorted bombers were shredded by fighters.

The USAAF bombing campaign against Germany began in earnest in early 1943, it was based on a number of untested theories which planners hoped would bring an early end to the war. [National Archives]
Since before the war, it was commonly believed among the Air Corps senior officers that a formation of well armed bombers was capable of defending itself from whatever threats it might face. This assertion would be disproven, as even the small raids against targets in France and the low countries sustained casualties that made consistent raids impossible. In early 1943, the next step of the campaign would be far more ambitious, moving on to targets deeper within Germany itself. The need for a long range escort fighter had already become apparent before this point, and work was underway to produce external fuel tanks for existing fighters, but the offensive would be continued without a fighter aircraft able to accompany raiders for the full duration of their missions.

Throughout the summer and autumn of 1943, the USAAF would launch numerous raids against targets in Western Germany, though the bombers could only be escorted over the low countries by P-47’s and P-38’s. It wasn’t long until these range limitations were understood, and soon after, exploited by the Luftwaffe. Wherever Luftwaffe fighters were untroubled by Allied fighters, they were free to make use of their most effective anti-bomber tactics.

Generalmajor Adolf Galland’s prescribed method of attack for single engine fighters was to make head on, or oblique, attacks from slightly above the bomber formation, carried out by at least a Schwarm, or two pairs of fighters (Marshall & Ford 267). This achieved two things, it increased the closure rate to reduce the likelihood of being hit by defensive gunners, and it was from this position that both the pilot and copilot of the bomber were most vulnerable. In the absence of escort fighters, Luftwaffe pilots would be able to regroup, fly ahead of the formation, climb, and repeat the attack. The lack of escort fighters also meant the Luftwaffe was safe to employ its two engined fighters against bomber formations, which with their heavier armaments, were much better equipped to bring down bombers. Over time their tactics grew even more complex as dedicated aircraft, typically Ju 88’s, were tasked with shadowing bomber formations to pass their altitude, course, and speed to flak and fighter control services.

Many Luftwaffe aircraft would be re-equipped to take on heavy bombers, like this Bf 109G-6 with its underwing 20mm gun pods. [Bundesarchiv]
Prior to the arrival of the P-51’s, the USAAF had two suitable fighters for the purposes of escorting bombers at high altitude, the P-38 and P-47. While they had the high altitude performance, they did not have the range to reach deep into the continent. The issue would be partially resolved through the addition of external fuel tanks, which had been discussed at a conference with the Material Division at Wright Field in March of 1942 (Ethel 51). Work however, was slow and the 108 and 75 gallon drop tanks were not delivered in large numbers until the end of summer, 1943.  These tanks would allow the shorter ranged P-47 to be able to cover bombers over their flight over the low countries, and the P-38, over the Rhineland. It should also be noted that the escort range was considerably lower than the maximum combat range of the aircraft, as the planes flew in a zig-zag pattern overhead so as not to out pace the bombers. Supplies of larger volume fuel tanks which would take the fighters further into German air space would not be available until the spring of the following year. External fuel tank development and procurement had been mismanaged by Army Air Force leadership who were still largely convinced that the bomber’s defensive capabilities were adequate. Had there been a greater supply, and larger volume tanks initially available, the P-47 and P-38 could have escorted bombers over most of Germany. To make matters worse, the P-38, which by then handled the most important leg of the trip, was troubled by a number of technical issues. While the P-38 possessed good high altitude performance, an exceptional climb rate, and a heavy armament, it was handicapped by a cockpit that pilot’s rated the worst of any US fighter in service and had flying characteristics that made it difficult for pilots to aggressively pursue Luftwaffe aircraft (Dean 164). The large, twin engine Lightning also had an unmistakable appearance, such that Luftwaffe pilots would almost always spot and identify the Allied plane before Lightning pilots could do likewise. With this benefit, Luftwaffe pilots were typically the ones who dictated the engagement, and would depart when conditions were unfavorable. On the defense they would have another advantage, both the Fw 190A and the Bf 109G were capable of out maneuvering the P-38 in high speed dives. The P-38 encountered severe compressibility issues at speeds significantly lower than those encountered on the two German fighters (Marshall & Ford 441). Thus, while the P-38 was capable of performing long range escort missions, its pilots would be forced to employ more conservative tactics than those used in the P-47.

By the start Autumn of 1943, USAAF planners were hoping to accelerate their progress on Operation Pointblank. This plan would see bombers raid targets that were vital to the German aviation industry in order to achieve air supremacy over Western Europe before an invasion of the continent. While losses for these raids were still extremely high, it was hoped that dispatching a larger force capable of inflicting serious damage would make it worth it. On August the 17th, the 8th Air Force prepared for its largest raid yet, with 376 B-17’s dispatched to attack the ball bearing works, at Schweinfurt, and a Messerschmitt factory, at Regensburg. Both of these facilities were located deep within Germany and most of the journey would see the B-17’s outside the area where they could be escorted. To compensate for this, the flight over Regensburg would continue over the Alps and into Allied controlled Tunisia. It was hoped that flight over the Alps would prove easy, and in the case of the Schweinfurt force, they believed that the German fighter squadrons would still be on the ground refueling after their first attacks while the bombers made their return. Both would be met with disaster as the Luftwaffe would hit both forces after their escort fighters turned for home, and the Luftwaffe fighters had taken to the air again as the Schweinfurt raiders made the return trip.

The bombers of the USAAF flew in staggered formations in order to maximize the the defensive capabilities of the aircraft. These tactics alone proved totally inadequate to protect bomber formations from fighters and were revised several times to compensate for flak. [National Archives]
Of the 376 bombers to leave England, 60 would be shot down, 176 were damaged, and 30 remained in North Africa where they awaited repairs at the overburdened facilities in Tunisia. Losses in combat and written off airframes amounted to 31% of the dispatched force; in contrast the Germans lost only 28 fighters (Overy 340, 341). Following the disaster, the 8th Air Force would carry out raids only where there was full escort cover and the next deep incursion into German airspace would only be conducted in the spring of the following year. The winter of 1943 would spell uncertainty for the campaign, as it was clear that for all intents and purposes, much of German industry lay beyond striking range. With this limitation threatening to seriously cut back the USAAF’s campaign, they would request that Lockheed, Republic, and North American increase the internal fuel capacity of their fighters, and hoped that a suitable long range escort would materialize.

Leaving the Stable

Col. Charles McCorkle, 15th AF with pilots. The P-51B proved the solution to the problems plaguing the ailing strategic air campaign. [National Archives]
As a result of the pressure to produce new, long range fighters for the escalating campaign in Europe, the first P-51B’s were produced before the prototype had gone through its testing and modification cycles. The first plane, a P-51B-1, was completed March 31, 1943 and would include several features that would later be found unsound on prototype. As a result, these initial planes would have to be altered accordingly and would have many parts that were non-interchangeable with later models (Marshall & Ford 316). In addition to reworking the air scoop and radiator, they would also have their ailerons modified, both to improve their effectiveness and to remove a steel diaphragm which would interfere with the plane’s magnetic compass. Most importantly, the decision was made that the aircraft would incorporate an additional 85 gallon fuselage fuel tank which would provide the aircraft with phenomenal range.

With this new aircraft, the USAAF would finally possess what they had been searching for. With the addition of the new internal fuel tank, the aircraft would be capable of deep incursions into German airspace, and it would deliver on what was promised back in the spring of 1942. They were excellent fighters, especially at high altitude. The early P-51B’s would use the Packard V-1650-3 engine, a license production of the British Merlin 61, which produced 1410 hp at 29,300 ft and 1630 hp at 16,400ft at War Emergency Power (P-51 operation manual 31). This engine would later be replaced with the Packard V-1650-7 in later models of the aircraft, which was geared for better performance at medium altitude. These engines, combined with the low drag fuselage and laminar designed wings would provide the aircraft with a superb climb rate, a high top speed at altitude, and exceptional high speed maneuverability.

While the aircraft had taken a largely completed form with the P-51B-5 and P-51C-1, it would be continuously modified in the field and on the production line, throughout its service with the air force. The most notable of these changes were the additions of a fuselage tank, booster motors for its ammunition belts, a vertical fin extension, and field retrofits for a perspex canopy dubbed the Malcom Hood. However, only the 85 gallon fuel tank would be a universal addition.

The fuselage tank would enable the P-51B’s to reach much of central Europe from England, but it was not present in the first deliveries of the aircraft, as was the case with the 59 P-51B’s active in England at the end of November 1943. The installation kits were first sent out in September of 1943, and the tank was later incorporated into the production run with the first long range P-51B being accepted by the Army in December of the same year (Marshall & Ford 393, 407).

The next addition to the aircraft was intended to solve a major issue with the plane’s machine guns, which were found to be prone to jamming when the pilot pulled turns of over 1g. This issue was a result of the canted position of the guns in the wings which put stress on the ammunition belts. The ideal solution was to reposition the guns, but seeing as that would necessitate a considerable redesign, engineers would instead work in a stop gap measure in the form of boost motors for the ammunition belts. These were issued as kits like the fuel tank, though unlike those for the fuselage fuel tank, they were issued in more limited numbers and the issue persisted well into 1944 (Ethell 64).

The Mustang had long had a tendency to yaw in the opposite direction of a roll, which affected its handling since its earliest models, and this was made significantly worse when fuel was carried in the fuselage tank. Despite the problem being an evident and considerable inconvenience, its solution wouldn’t materialize until much later. Eventually, it was decided to fit the aircraft with a fin extending from its vertical stabilizer, along with adding reverse rudder boost tabs. However, these kits arrived very late, having begun production in April of 1944, and later incorporated into the design of late P-51C’s and the subsequent P-51D (Marshall & Ford 306).

The Malcom Hood provided far better visibility than the earlier ‘birdcage’, and was added to a number of P-51B’s based in Northern Europe. [National Archive]
Many long standing issues revolved around the ‘birdcage’ canopy of P-51 since the aircraft’s inception, and as was the case with the engine, an improvement was found in British service. With the RAF, many Mustangs received a new frameless bubble canopy. This canopy vastly improved visibility, especially to the rear of the aircraft, which was virtually non-existent from within the birdcage, and it could be drawn back on landing and take-off. Dubbed ‘Malcom Hoods’ after their manufacturer, a plexiglas works named Robert Malcom Ltd. they were subsequently sought after by the USAAF for use with their P-51’s in Europe.

Breaking the Stalemate

The new P-51B’s would make their first major debut with the 8th Air Force in early 1944, though the introduction was not as smooth as had been hoped. Squadrons reported a number of issues with the new aircraft, which included high altitude fuel transfer failures with external tanks, glycol reserve tanks that leaked and froze, radiator corrosion and coolant leaks, radios and spark plugs failing, and excessive oil loss (Marshall & Ford 425). However the USAAF hadn’t the time to immediately resolve these teething issues, and with these problems passed along to the manufacturer and Air Force maintenance services, the P-51’s would soon play a key role in the escalating bomber offensive.

Through the winter of 1943, both the day and night bombing campaigns were facing withering losses which spelled serious trouble for maintaining the pace of operations over Europe. With less than one thousand bombers stationed in England, the USAAF would lose 200 in September alone (Douglas 326). In the face of these losses, the Combined Bomber Offensive was failing to carry out the Pointblank directive, which aimed to cripple the Luftwaffe before an invasion of Europe was conducted. During this period the Luftwaffe had actually built up the strength of its fighter force and had reorganized and improved its defenses into a centralized command structure. To make matters worse, the head of RAF’s Bomber Command, Arthur Harris, would ignore orders to attack German industries involved in aircraft production. Instead, he would order Bomber Command to continue to carry out an ineffective area bombing campaign of Germany’s cities believing it would bring an end to the war without the need for an invasion (Overy 343, 344). It was under these bleak circumstances that the US’s Eighth and Fifteenth Airforces were tasked to cripple the Luftwaffe and establish air superiority over much of Europe before the invasion, now only a few months away. However, they would soon see a change in leadership and the delivery of new equipment that would put them on the path to controlling the skies over Europe.

Escort fighters typically flew a few thousand feet above their charges when they weren’t independently seeking the enemy. They weaved back and forth over the bombers in order to not speed past them. Here a flight of four P-51’s flies overhead at roughly 30,000 ft. This tactic declined in use when the relay system came to prominence. [National Archives]
In December of 1943, the USAAF established a joint strategic air command to consolidate their bomber forces over both the European and Mediterranean theaters, and drive them towards a unified objective. With Gen. Spaatz in command of all strategic bomber forces, and Maj. Gen. James Doolittle in command of the Eighth Airforce in England, the USAAF would now have clear strategic direction, and more aggressive leadership. Doolittle would take a pivotal role in revising the existing strategy into one which proved instrumental in undermining, and dismantling the Luftwaffe in the coming weeks. Crucially, he recognized the inadequacy in trying to undermine the Luftwaffe’s fighter strength solely through targeting the production of new aircraft. To hold to this existing, overly conservative strategy was hopeless, and the invasion of France was scheduled for five months after he took office. Targeting the factories alone wasn’t enough, and thus Doolittle would give the order for returning escort fighters to perform fighter sweeps and seek out enemy planes in the air and on the ground (Overy 361). Among the first and most important moves was to create a more effective relay system for the fighters, further increasing the time they could spend over enemy territory.

By the start of 1944, Maj. Gen. Kepner, 8th Air Force, would also play a major role in implementing this new strategy, as he officially untethered the Eighth’s fighters from the bombers and allowed them to seek out the enemy at their discretion. The P-51 would play a pivotal role, as its excellent high altitude performance and range meant it was able to take up the last position of the fighter relay, and was more than a match for whatever it found. Beyond the existing penetration, target, and withdrawal relay positions, the P-51 was also able to take up a fourth mission. These units would perform sweeps 50 to 70 miles ahead of the bomber formation and attack German fighters as they were climbing, assembling, or transiting towards the bomber formation. Their efforts were greatly aided by British signals intelligence services that provided the assembly points for the Luftwaffe’s fighter groups (Marshall & Ford 425, 425; Overy 362).

This change in tactics would have immediate and profound impacts as they began to be widely implemented in February and March of 1944. The first major achievement of the new strategy were the widespread losses inflicted on the twin engined fighter forces, which had earlier proven themselves as potent anti-bomber weapons. Against the new long range fighters, they were almost defenseless, and were withdrawn in March (Overy 366). Similar effects were felt throughout the Luftwaffe’s fighter forces, which thanks to the new P-51’s, were left without any safe haven. Whenever the bombers were over Germany, their escort fighters could make their appearance. While the new strategy often meant that the bomber formations were often less protected, this was counterbalanced in that it placed the German fighters on a defensive footing. The days of Luftwaffe fighters leisurely climbing alongside a formation before diving at it head on were over, now whenever they reached a formation they were forced to conduct hit and run attacks, or face off against the escorts.

Luftwaffe attrition escalated as airfields that were once ignored were now periodically harassed by fighters that attacked transiting and grounded aircraft. Doolittle did all he could to promote these attacks, and would allow for the destruction of aircraft on the ground to count towards a pilot’s ace status (Marshall & Ford 423). These attacks would prove costly to the USAAF, but well worth it as Luftwaffe operational losses for all aircraft increased sharply and it robbed them of the ability to train new pilots in secure airspace. This shift in strategy and subsequent success would prove instrumental to the USAAF in the following months, as their responsibilities were soon to broaden when the Allies landed in France.

When equipped with external fuel tanks, the P-51B could operate over any part of Germany. This proved disastrous for the Luftwaffe as transiting aircraft and those on the ground were now vulnerable, no matter how far they were from Allied air bases. [National Archive]
While the Eight and Fifteenth air forces were still occupied with the task of destroying the Luftwaffe in the air and on the ground, they would soon be given additional missions. The most unexpected of which came in the form of Operation Crossbow, which called upon the Eighth Air Force to disrupt Germany’s use of the new V-1 bomb from coastal bases. Then came the task long awaited, which called upon the Eighth to begin the preparations for Operation Overlord. To meet these new objectives, the Pointblank raids were accelerated, culminating in ‘Big Week’ in February of 1944.

Between the 19th and the 26th, the Eighth and Fifteenth air forces would fly roughly 6,200 sorties against 18 aircraft assembly plants and two ball bearings plants, at a loss of 247 bombers and 28 fighters. Undoubtedly steep, but sustainable in comparison to the Luftwaffe which lost roughly one third of its single engine fighters (Overy 369). The success of the raids themselves was difficult to judge, as fighter production still increased, though at a significantly reduced rate which saw a shortfall of roughly 38.5 percent (Overy 370). During these operations the P-51 would provide the USAAF deep penetration cover and perform strafing attacks against German airfields. However, there weren’t enough long range escorts for full coverage until the summer of 1944. The situation was further complicated when all P-51B’s were grounded between the 10th through the 15th of March in order to address structural issues with the aircraft’s engine mounts, wings, and tail. These were subsequently resolved by replacing the retaining bolts for the engine, reinforcing the tail empennage and ammunition doors, and installing landing gear locks to prevent their uncontrolled release at high speed (Marshall & Ford 442, 446). These issues would however not present a long term obstacle during the early months of 1944 as the tempo of operations and list of targets grew in the following months.

With the major push against the German aviation industry mostly over, the USAAF would soon set its sights on two major targets, rail communications across much of Northwestern Europe, and Germany’s oil industries. The first was an immediate necessity for the success of Operation Overlord, crippling German strategic mobility was essential for an invasion which would require considerable time after the first landings to build up a force on the continent. The formalities were worked out in March when the Transportation Plan was decided upon. It would fortunately have the support of RAF Bomber Command, as Harris’s evident failure to end the war on his terms would see him temporarily divert his force into supporting the preparations for the invasion of France. The subsequent offensive against fuel production would start far less formally. Spaatz was convinced of its necessity, but due to the months it would need to take effect, he was at first unable to convince his superiors to divert resources to it. However, in a matter of weeks, he was able to argue for its necessity under the Pointblank Directive and was then allowed to conduct attacks against Germany’s synthetic fuel industry whenever resources permitted (Overy 371).

Between the now crippling fuel shortage and marauding allied fighters, the Luftwaffe soon found themselves completely overwhelmed by the autumn of 1944. Here a P-51 lines up on an He 177 heavy bomber, as the one beside it continues to burn. [National Archives]
With these new policies in place, the Luftwaffe would be thoroughly disrupted as a result of Spaatz’s strategy, and Doolittle and Kepner’s tactics. The USAAF would end up inflicting punishing losses on the Luftwaffe in the air, disrupting the manufacturing of new aircraft, and eventually causing chronic fuel shortages that severely limited their ability to conduct large scale operations of any kind. In this, the P-51 would prove essential with its exceptional high altitude performance, and its endurance that could take it anywhere over Germany.

In many ways, the bombing of factories alone was a largely ineffective means of inflicting serious damage to the German war economy, as many industries proved to be exceedingly resilient. Fighter production proved a particularly difficult target, as apart from the later targeted aero engine industry, production and final assembly plants could be dispersed and were largely safe from raiders. When fighter production was further streamlined and resources were diverted to support it, Germany would end up vastly expanding fighter production during the period in which those industries were the most frequently raided (Zeitlin 59). This was, however, was achieved only by reducing the rate of modifications and improvements, and transferring resources away from the production of bombers. In comparison, the later targeting of fuel production and rail transportation proved key, as the inability to reliably move material by rail combined with chronic fuel shortages proved a fatal military and economic obstacle. As a result, establishing air supremacy over Western Europe before Operation Overlord was as much an achievement of long range fighter operations as it was of the bombers. The Luftwaffe could sustain itself when aircraft deliveries did not meet expectations, but it quickly found itself struggling when it lost scores of pilots and found itself hard pressed to train new ones once they had lost control of the skies over Germany.

Pre-war military theorists envisioned fleets of bombers destroying vital war industries with the near pin-point accuracy they achieved in controlled tests. The reality of the campaign revealed this as hopelessly optimistic when even the most accurate raids resulted in large amounts of collateral damage. [National Archives]
In the end it must also be said that the civilian costs of the raids were steep, and while the Eight and Fifteenth Airforces were not involved in a campaign directed against the civilian populace, as was the case with Bomber Command and the USAAF elsewhere, the technical limitations of the time meant that bombs frequently fell on civilian areas. Even under ideal circumstances, the dimensions of a bomber formation were larger than their targets and it was physically impossible to strike factories, railyards, and refineries without causing significant damage to the surrounding area. The realities of the campaign would also prove worse than predicted. Targets were frequently obscured by bad weather and smoke generators, and formations typically took heavy anti-aircraft fire on the approach. As a result, bombs were often released by the best estimate from the bomb sight or at the direction of a ground mapping radar system (Overy 347). Even outside of Germany, the civilian costs of these operations were heavy as the Allied air forces carried out the transportation plan. In France alone, between March and June of 1944, French officials placed the figure of civilians killed by Allied bombing at 25,266 (Overy 574).

The 4th Fighter Group ‘Debden Eagles’

When the US entered the Second World War, few American airmen had any combat experience, with the notable exceptions being volunteer airmen in service with foreign armies. The Debden Eagles were one such group, having volunteered to serve with the RAF and entered service in late 1940 and 1941. While they were among the few Americans fighting against Nazi Germany at the time, they had garnered a somewhat unfortunate reputation as glory-seekers and primadonnas thanks to their unique position (Bucholtz 6). Their tendency of excessive overclaiming of victories during this period would prove particularly irritating to their superiors. With the US entry into the war, the Eagle squadrons, and their Supermarine Spitfires, were subsequently integrated into the USAAF.

Capt. Donald Willis, an Eagle Squadron pilot alongside a Spitfire Mk V, late 1943. [National Archives]
The RAF’s 70th, 121, and 133 Eagle Squadrons would become the 334th, 335th, and 336th Squadrons of the 4th Fighter Group on the 12th of September 1942. These units flew Spitfire Mk IX’s and within the month were supporting the nascent bomber offensive which was targeting installations in France. The start of this effort went poorly, when only one aircraft out of a twelve plane flight returned, the rest having been lost to enemy fighters, harsh weather conditions, or having run out of fuel in the short range fighter. Thankfully for the Group, this would be their worst day of the war. Despite this setback, the unit saw its first major mission carried out on the 20th of October in the Calais area escorting B-17’s carrying out a high altitude raid. This would be the first major bomber operation carried out under escort and was met with success. Their Spitfires would prove a very capable fighter aircraft, but their short range rendered them unable to conduct escort missions far beyond the English Channel. In any case, this wouldn’t prove much of an issue, as for the rest of the year as they would mostly conduct fighter sweeps across the low countries and provide convoy cover (Bucholtz 9). However, with the changing of the year, the 4th would exchange their venerable Spitfires for new P-47’s.

The 4th FG flew their Spitfires in combat for the last time on April 1st, 1943, after which they completed the full transition to P-47C’s. This change was not viewed favorably, as most of the unit’s pilots disliked the considerably heavier Thunderbolt (Marshall & Ford 340). The changeover had little initial impact on operations, and the squadron was largely involved in the same missions as before. However, the group would later accompany bombers on deeper raids into Europe thanks to newly issued external fuel tanks for their P-47’s. They would use these new 200 gallon fuel tanks on an escort mission into Ghent on July 25th and soon after their first foray into Germany airspace over Westhoff-Emmerich. It should be noted that these fuel tanks were a rare piece of equipment at the time and the 4th only had them thanks to the efforts of Lt. Col. Cass Hough of the 8th Fighter Command’s technical section. They were, unfortunately, as troublesome as they were vital, often failing to transfer fuel above 20,000, and were later withdrawn as British made paper 108 gallon tanks became more available (Marshall & Ford 411).

Despite their complaints, the 4th FG’s veteran pilots would master their new planes and had put them to good use. In a battle defending a formation of B-17’s over the city of Utrecht, the 4th FG was credited for the destruction of nine enemy aircraft at the cost of one of their own, with the pilot having bailed out over the occupied Netherlands (Bucholtz 16). With their P-47s, the 4th would take up an important supporting role in the escalating bombing offensive, one which saw their longer ranged P-47s making more flights into the German frontier. This tempo and the 4th’s change in command under the more aggressive Lt. Col. Don Blakeslee would see the unit become among the most successful in the entire USAAF.

Col. James Matthew Blakeslee would lead the 4th FG from January to November 1944, after which he remained on the ground after several high profile pilots of the USAAF had been lost in a short period of time. He is pictured here receiving the Distinguished Service Cross from Supreme Allied Commander in Europe, Dwight Eisenhower. [National Archives]
Lt. Col. Blakeslee was made C.O. of the 4th with the turn of the year, and in addition to bringing new, more aggressive tactics to the table, he would work to ensure his unit was re-equipped with the new P-51. Blakelsee would meet personally with General William Kepner and argue that his squadron would be the best candidate for refamiliarization with the new plane as their experience with the similarly-engined Spitfire would make for an easier transition. Kepner was convinced, and subsequently put the 4th FG at the top of the list for P-51’s. The schedule for the transition was harsh as they continued to fly combat missions in their P-47’s while also familiarizing themselves with the new aircraft. The process was time consuming and they would not make their operational debut with their new planes until February 28, 1944 (Marshall & Ford 432). These Mustangs would nearly double the combat range of the unit, and the pilots favored them over their older P-47’s, but they experienced a variety of harsh teething issues and mechanical failures.

While the conversion was taking place, the 4th would be committed to Doolittle’s more aggressive strategy against the Luftwaffe, with the aim to achieve aerial supremacy over Western Europe before the invasion of France. As such their independent actions increased, and on January 31, 1944, they would join the 355th FG in bombing the Luftwaffe’s airfield at Gilze-Rijen (Marshall & Ford 425). In many ways this mission bore some similarity to the fighter sweeps they had conducted since they had flown with the RAF, but it would mark a first in that direct assaults on Luftwaffe airfields would then become more commonplace. Among the last major actions the unit would perform with its P-47s was its support of ‘Big Week’.

Their first combat mission in the new planes was fairly uneventful, on February 28, when flying as escorts for a formation of bombers attacking a V-1 launch site they encountered no enemy aircraft but strafed a Ju 88 on their way home. They would claim their first aerial kills two days later during a bomber withdrawal support mission near Frankfurt where they claimed two enemy fighters (Bucholtz 38). The following day the unit would help achieve a major milestone, the first fighter escort operation to Berlin and back. The operation would prove anything but easy, as deteriorating weather conditions saw most of the aircraft involved turn back. However, elements of the 3rd Bomb Division would press on, supported by the 4th, 55th, 354, and 363rd FG’s. The 4th would engage a formation of roughly 60 Fw 190’s and Bf 110’s northeast of Wittenberg in the day’s first encounter with the enemy. They claimed five victories but suffered one loss from enemy fire, and another as a result of a radio failure which made navigation across a storm in the English channel impossible. The pilot was later forced to ditch his aircraft in France after a failed attempt to reach neutral Spain (Marshall & Ford 439, Bucholtz 39).

Capt. Don Salvatore Gentile was among the leading aces in the 4th FG. He was credited with 21 aerial and 6 ground victories, though his combat service ended after a botched aerobatics stunt in front of assembled members of the press. He was grounded and went on a tour to raise war bonds, later becoming a test pilot. [National Archives]
Perhaps the most exciting encounter that day was experienced by Capt. Don Gentile and Lt. John Godfrey, both aces in the 4th. The two pilots were unable to join the rest of their flight as a result of extremely poor weather, but proceeded with their mission regardless. En route the weather would clear, and reveal a flight of roughly 50 Do 217 night fighters, pressed into service as daylight bomber destroyers, and dozens of Fw 190’s which were preparing to attack a nearby formation of USAAF bombers. The pair would decide to attack, in order to disrupt the enemy formation and prevent them from engaging the nearby bombers from an advantageous position. Gentile and Godfrey dove on the night fighters, damaging one and sending the group diving in an effort to escape. The engagement turned into utter chaos as the single-engined fighters joined in. In the confusion, the pair of aces would claim one enemy aircraft in a series of defensive fights that eventually saw them make their escape through the clouds. Flying on instruments and practically lost, they made their way back to England by their intuition, landing at RAF Hurn (Bucholtz 40).

The unit would return to Berlin on March 6 in support of a massive 8th Air Force operation. Favorable weather conditions would allow the 8th to dispatch a force of 730 bombers against a series of targets in and around the German capital, where they would meet the Luftwaffe in the largest air battle of the war up to that point. The 4th, led by Col. Blakeslee, would be tasked with escorting the bombers, which would prove a difficult undertaking, with the sheer number of opponents forcing the group to disperse into individual flights and sections to expand their coverage. The unit would be credited for the destruction of 15 enemy aircraft of the 45 claimed by P-51’s that day, in exchange for five losses. In comparison, P-47 units were credited with 37 kills for 5 losses, and P-38 units brought down three units at the cost of three of their own. It should also be noted the P-38’s comprised the minority of the fighters, while there were roughly twice as many P-47’s as there were P-51s. The USAAF would claim a total of 83 ‘confirmed’ enemy aircraft with the Luftwaffe having recorded the loss of 75 fighters (Marshall & Ford 439; Bucholtz 43, 45). The majority of these kills were twin engine and night fighters pressed into daylight service. This engagement, while not representing a distinct turning point, did demonstrate a noticeable shift in the war over Germany. Of the 672 bombers that proceeded with the mission, 69 failed to return, and 6 were written off. These were certainly heavy losses, but were a fraction of the nightmare that the Allies were facing in the summer and autumn of the previous year. Beyond that, Luftwaffe losses were mounting both in the sky and on the ground, and the use of its heavier, twin engined bomber destroyers had become untenable in the face of agile new opponents.

D-Day

During the first day of Operation Overlord, most fighter units were dedicated to countering a Luftwaffe response that never came. Several would go on to attack inland targets. [National Archives]
Over the coming weeks the 4th would continue to support the bombing campaign, but in June of 1944 they would participate in something far more decisive. The group would be among the many fighter units providing top cover for the invasion of Normandy. Throughout D-Day, each of the unit’s three squadrons would operate independently and continuously until nightfall. The day began with the 334th and 335th squadrons undertaking an offensive patrol under the command of the unit’s C.O., Col. Blakeslee, between 03:20 and 09:45 over Rouen, France. The patrol found no enemy fighters and sought out targets of opportunity, in their case a pair of locomotives that they strafed with their machine guns. Their only loss was 1st. Lt. Fraser, who had lost contact with the rest of the squadron and was subsequently downed by German fighters and taken prisoner. The 336th would sortie at 06:42 to provide cover for warships shelling the landing areas, which proved uneventful (Bucholtz 84).

At 11:20, the 334th would sortie again to Rouen with one section carrying bombs. They would attack a troop train to poor effect, though an encounter with a flight of 10 Fw-190 near their airfield at Evreux proved more successful. In the ensuing battle the 334th was credited with the destruction of four enemy fighters, with the only damaged P-51 making it back home. While this confrontation was happening, the 335th had attacked the marshaling yards at Fleury. The 336th would fly for the last time that day at 13:35 conducting a fighter bomber sweep near Evraux. They would find no targets and would lose an aircraft to ground fire, with 1st Lt. Freiderick being taken as a PoW. The last mission of the day would see the 334th and 335th conduct attacks against a radar station and a road convoy near Rouen. While successful in their mission, they incurred heavy losses when elements of the unit were attacked by around 15 fighters belonging to JG 2 and JG 26 as the US fighters attacked infantry positions.

Capt. Winslow Sobanski was a Polish infantryman at the outbreak of the war, eventually finding his way to the US where he then joined one of the Eagle Squadrons. He was among those killed in action during the group’s last sortie on D-Day. Pictured here in a P-47. [National Archives]
The day would prove exhausting, with pilots flying up to three missions from dawn to dusk. Between flights most of the 4th’s pilot’s would rest, usually either having coffee or trying to get some sleep in before their next mission. The different squadrons would also find themselves having vastly different experiences, with the 336th having spent most of the day covering the invasion force which the Luftwaffe hadn’t the strength to attack, and taking part in a fighter bomber sweep that found no worthwhile targets and saw one aircraft lost to flak. In comparison, the 334th and 335th spent the entire day conducting offensive sweeps which claimed a number of targets, but also saw them sustain higher casualties than any of the other US fighter squadrons over Normandy that day with ten fighters lost (Bucholtz 82, 83).

Shuttle Mission to VE-Day

Following the success of the landings, and subsequent breakout in Normandy, many of the USAAF fighter units would take on tactical missions in support of the armies in Western Europe, in addition to the ongoing strategic air campaign. However, some P-51 units were selected to participate in an escort mission in which the bombers would land at prepared airfields in the Soviet Union instead of returning to their home bases. A 45 aircraft detachment of fighters from the 4th would depart for the Soviet Union on June 20th. The mission would see them join a force of 1,000 bombers as they attacked targets in the Rhineland, and then on to Piryatin, Ukraine some seven hours away. 45 Mustangs of the 4th would make the trip, encountering some 25 enemy fighters over Siedlice, downing two, but losing one of their own. All but one of the remaining planes landed at their intended destination, with one 2nd Lt. Hofer being forced to land at Kiev after running low on fuel after pursuing enemy fighters (Bucholtz 88). However, unbeknownst to the assembled American aircraft, the formation had been trailed by a Ju 88. Soon after, a well coordinated attack by the Luftwaffe using its He 177 heavy bombers saw many of the US bombers hit, though their P-51’s were unscathed.

The P-51’s were subsequently dispersed and flew a variety of missions in the following weeks which brought them over Central Europe and the Mediterranean. They soon flew an escort mission against an oil refinery in Drohobycz, Poland on the 26th. The return leg of the mission took them to Lucera, Italy where they would support the bombing operations of the 15th Air Force. The largest of these missions would take them over Budapest to perform a fighter sweep ahead of the strike force. There they encountered 80 German and 18 Hungarian Bf 109G’s and a massive dogfight ensued. In the battle the 4th would claim eight Axis fighters at the cost of four of their own. This included 2nd Lt. Hofer who had died during a strafing attack against an airfield. (Bucholtz 89). The unit would be led back to England on the 3rd of July.

American and Soviet personnel during Operation Frantic. [National Archives]
Beyond Operation Frantic the 4th settled back into the ‘usual’ operations they’d had since most of the group had left for the Soviet Union. They continued to fly deep penetration and escort missions over Germany, though by the end of the summer, Luftwaffe activity in the air had been considerably reduced. The savage war of attrition over Germany had been decisively won by the USAAF, as the Luftwaffe began to feel ever more crippling shortages of experienced pilots and fuel. Ironically, the Luftwaffe’s supplies of fighter aircraft were secure, though transporting them to airfields would prove ever more troublesome through the remainder of the war. While they had the aircraft, a subsequent USAAF campaign against rail communications across Germany would make overland transportation difficult, and ever more frequent fighter sweeps made transiting by air a very dangerous prospect.

For the remainder of the war the 4th FG remained committed to supporting the strategic bombing campaign, especially as it pertained to offensive fighter sweeps and attacks against Luftwaffe airfields. Their last victory of the war was a probable destruction of an Me 262 that was damaged over the Prague/Ruzyne airfield, with the group credited for 1,058.5 total victories against enemy aircraft, both in the air and on the ground (Bucholtz 120). They would end the war among the most successful Fighter Groups in the USAAF, having come a long way from the overly boastful volunteers that had flown against the Luftwaffe before any other Americans.

The 99th Fighter Squadron ‘The Tuskegee Airmen’

As black aviators, the men of the Tuskegee-trained squadrons would face unique challenges, having to face prejudice from their own countrymen who sought to deny them the opportunity to fight. They were initially excluded from many of the pre-war programs that turned out many of the pilots who later joined the ranks of the USAAF and US Navy. Many who ran these programs espoused the belief that they were incapable of the judgment needed for leadership, and that they had lacked ‘the proper reflexes to make a first class fighter pilot’ in the words of General Edwin J. House (Moye 102).

Their chance came with the Civilian Pilot training program in 1939, having been excluded from the program the previous year. The program was extended to a series of predominantly black colleges and universities, with the most critical being the Tuskegee Institute in Alabama. The university would build a fledgling airfield that eventually grew into an Army Air Corps training base, which proved controversial even among hopeful applicants, as in their eyes they were clearly still segregated from the rest of the Army. While the controversies flowed in the small Alabama town, the Air Corps moved to create the first black pursuit squadron, the 99th.

Col. Benjamin O. Davis would lead the 99th fighter squadron and the later 332nd Fighter group. He would go on to become a Brig. General in the newly formed United States Air Force after the war. [San Diego Air and Space Museum]
The first cadets of the 99th would graduate March 7, 1942 under the command of Capt. Benjamin O. Davis. The squadron would subsequently fly within the US before its transfer to the Mediterranean in late March 1943, equipped with new P-40L’s (Moye 99). They occupied a former Luftwaffe airfield in Morocco and were to be attached to the 33rd Fighter Group after they had gotten some experience in theater. In May, the squadron would be deemed ready for service and would move to a field in Tunisia. They would see success there, but the leader of their fighter group, Col. William Moymer was immediately hostile to their presence. He failed to return the salutes of the 99th’s officers and he placed the squadron on patrol duties over secure air space. He would then openly criticize them for being ‘unaggressive’ for failing to claim victories over territory where they were unlikely to encounter enemy aircraft (Bucholtz 18, 19; Moye 101). In spite of this, the unit pushed on and would aid in the preparations for the invasion of Sicily.

The 99th’s first combat missions were fighter sweeps against enemy positions in Southern Italy, their first target being a German airfield on the island of Pantelleria on June 2, 1943. The airbase would be the site of many more attacks, including the unit’s first encounter with enemy fighters. On June 9th, six P-40’s from the 99th Squadron accompanied A-20’s to the airfield, encountering four enemy fighters. In the ensuing fight they successfully drove off the enemy aircraft, and damaged one, taking no losses of their own. A further effort was made to intercept a flight of Ju 88’s at high altitude but were unable to, as their P-40’s had their oxygen systems removed to save weight for the low altitude mission (Bucholtz 21). The pilots of the 99th were particularly enthused that in their first encounter with the enemy, they had managed to complete their mission and all returned home safely.

While they would eventually be known for their iconic red tailed P-51’s, members of the Tuskegee fighter squadrons would fly the P-40L, P-39Q, and P-47D before they were issued Mustangs. [National Archives]
The squadron would be redeployed days later, partially a result of Moymer who sought to see the squadron reduced to coastal patrol duties. Instead, the 99th was transferred to the 79th Fighter Group, who’s commander, Col. Earl E. Bates, did his best to integrate the unit into the group. While they remained formally segregated, they enjoyed a far more open and professional environment than what they endured with the 33rd (Moye 103). Their first mission with the unit was on July 2 and saw them escort a flight of 16 B-25’s to their target, a German airfield in Castelvetrano, Italy. It would prove less than ideal when the B-25’s failed to line up with their target on the initial approach and had to repeat the attack, giving Axis fighters stationed nearby the time they needed to scramble. Two of the 99th’s pilots were lost in the first pass from the German fighters, but the remaining members soon regained control of the situation. In the ensuing confrontation with enemy Fw 190’s, Bf 109’s, and a Macchi 202, the 99th would claim one confirmed destruction, one probable, and two damaged aircraft. Though perhaps most importantly, none of the B-25’s they were escorting came to harm (Bucholtz 21, 22).

The coming weeks saw them mostly fly ground attack missions in support of the ongoing invasion of Italy, and met very few enemy aircraft for the remainder of the year. It was during this time that they also discovered that the Tuskegee training center wasn’t large enough to supply a sufficient number pilots to the squadron, while also supporting the construction of three additional squadrons. Their pilots resultantly flew an abnormally high number of missions due to being short handed (Bucholtz 25). This period also saw them defeat a great deal of the unfair criticism leveled against them and had largely cemented a favorable reputation within the Army Air Force. Among the most notable victories on that front was an article in Time, which had previously published an article based on Moymer’s alleged grievances with the squadron. Maj. Roberts of the 99th would be quoted “people assumed we were not producing because we were negroes…but now that we have produced, things have changed.” The 99th had also succeeded in convincing most of the 79th FG of their worth, and had garnered a great deal of respect as they moved into 1944. Many white pilots of the 79th disobeyed an order from the commander of the Air Force commander in the MTO, and held a desegregated dinner party to celebrate the anniversary of the 99th’s combat debut (Moye 104, 105).

Forming the 332nd Fighter Group

While 99th gained valuable experience over the Mediterranean, they began to rotate pilots out to train the next pursuit squadrons to form a segregated fighter group. These squadrons were the 100th, 301st, and 302nd, all of which would be formed at Selfridge Field, Michigan. Selfridge would prove a particularly dreadful post for these men, as it was here that they would face intense discrimination both by the local populace and base staff, while being a stone’s throw from the racial powder keg of Detroit. However, this would not remain their home for long, and they would soon depart for their operational assignments by the end of the year. They would join the 99th in the Mediterranean Theater of Operations in January of 1944, being equipped with a set of used P-39s. These aircraft would prove troublesome in service due to their age and condition, and as such numerous accidental losses followed, so by the early summer of 1944, Col. Davis had managed the acquisition of new P-47Ds. However, the unit would soon transition again to the newer P-51 soon after the 99th joined the rest of the fighter group in July, something the group’s veterans would resent as they felt they had been segregated again after finding acceptance within the 79th FG.

Capt. Andrew Turner aboard a P-51. The group’s transition to this aircraft vastly expanded the range and variety of operations across the Mediterranean and Central Europe. [National Archives]
The group would fully transition to Mustangs by July of 1944, and would be reassigned to the 15th Air Force where they would support long range bombing operations. Their first mission in their new planes was on July 4th, where they took 40 aircraft to to escort two bomber wings, but they would encounter only a pair of Bf 109’s that made no attempt to attack the allied aircraft . Beyond this, their pace of escort missions rose and they would take part in supporting raids against Axis positions in Northern Italy and Southern France. Soon after, they would provide support for the amphibious invasion of Southern France. On August 12, All four of the 332nd’s squadrons were given specific targets, with the 99th striking radar stations in Montpelier and Sete, the 302nd attacking radar stations in Narbonne and Leucate, the 100th attacked the radar stations near Marseilles and Cape Couronne, and the 301st attacked four targets around Toulon. At the loss of three pilots, one captured and two killed, all of the targeted radar stations sustained considerable damage .

The remainder of the war saw the 332nd fly a considerable number of escort missions, including an earlier attack against the Ploesti oil fields in Romania on July 13th, 1944. It was during that mission that they had begun to cement their status as one of the most reliable escort units in the USAAF, after they dispersed a flight of eight German fighters that had attacked bombers of the 55th Bomb Wing. Their C.O., Col. Davis maintained an unwavering directive to his unit, on escort missions they were never to abandon their bombers. This didn’t sit well with some but it was accepted, in part because many felt that a failure to protect the bombers would come down harder on them than the other squadrons (Bucholtz 51, 105; Moye 102). As such, their record for defending bombers was exemplary, having lost only 27 bombers to enemy fighters from June of 1944 to April 1945. It should also be noted that 14 of these losses occurred during a single day when a failure in mission planning resulted in the bombers and their escorts failing to meet at the proper time. As the target that day was the Luftwaffe air base at Memmingen, Germany, losses were correspondingly high (Bucholtz 53, Haulman 2). This places the remaining 13 bomber losses among the other 178 escort missions they performed over ten months. This policy would however, result in the squadron having the lowest aircraft kill to loss ratio of any other P-51 squadron in the theater, however, they would still consistently outscore all of the veteran P-38 squadrons in the Mediterranean (Marshal & Ford 477).

Among their most impressive escort missions was in support of a bombing raid against the Daimler-Benz tank assembly plant in Berlin, on March 24, 1945. From the 332nd’s base in Ramitelli Italy, this was a 1600 mile round trip, the longest mission ever conducted by the 15th Air Force. 59 Mustangs of the 332nd would leave their base at 11:45 under the command of Col. Davis, though he would soon return after experiencing engine trouble and left the squadron in the command of Capt. Edwin Thomas. They would encounter some two dozen enemy fighters outside of the German capital, including a number of Me 262s. The jets would initially prove difficult to catch, and the aircraft, belonging to JG 7, would at first disengage from the bombers whenever the escorts drew close. However, several of the jets would later press their attack on the formation. In the ensuing battle 1st Lt. Earl R. Lane, Flt. Officer Joseph Chineworth, and 1st Lt. Roscoe Brown would each be credited with a confirmed kill on three downed Me 262s. On their return flight they engaged several targets of opportunity, including two trains. The success of this mission earned the unit one of their three Distinguished Unit Citations, and the personal thanks of Gen. Lawrence of the 5th Bomb Wing (Bucholtz 108, 109).

Beyond their role as escorts for the 15th Airforce’s bombers, the 332nd would be engaged in a number of fighter bomber missions across the Meditteranean and Central Europe. These missions were conducted whenever time permitted between bombing raids and would see the squadron engage a number of targets. These would include airfields and various transportation targets varying from trains to river barges. A raid on August 30, 1944 would mark the unit’s most successful day when the 332nd attacked poorly camouflaged aircraft at Grosswardein airfield, Romania. In the ensuing strafing attack, they would be credited with the destruction of 83 aircraft with a further 31 damaged, ranging from 30 Ju 88’s, to a pair of super heavy Me 323 transport aircraft (Bucholtz 66). They would mount similar attacks against Axis airfields from Romania to Hungary.


Pilot’s of the 332nd, Lt. Clarence ‘Lucky’ Lester on the right, leads the group with 3 credited victories, all claimed on the same day. [National Archives]
The 332nd would end their campaign at an airfield in Cattolica, Italy, and was credited for the destruction of 111 aircraft in the air, 150 on the ground, 57 locomotives, 600 rail cars, and had flown 15,533 sorties (Bucholtz 116). It was a common myth that the squadron had never lost a bomber to enemy fighters, this being a rumor circulated by the press near the end of the war. This was not the case, but even with the failure over Memmingen, their bomber losses to fighters were half of the average and they were a considerable morale booster for the bomber crews of the 15th Airforce.

Flight Characteristics and Pilot’s Remarks

 

[P-51B pilot training manual]
The P-51B would prove to be an excellent fighter, but one that could present some challenges to those unaware of its quirks. It shared most of its general flight and handling characteristics with its older Allison powered predecessors, though some alterations to the design would make themselves felt, and not always to the plane’s benefit or pilot’s wishes.

Overall, the Merlin Mustang’s would prove to be fast and highly maneuverable, but with more complex flight characteristics than the Allison powered models that came before. Under most flight conditions, the plane was positively stable and possessed controls that were light and responsive. This aspect had been improved from the previous models, as the P-51B would be equipped with improved internally sealed and balanced ailerons which kept control stick forces light. These were rated very well, though pilots would note they were still ‘mushy’ at low speeds. However, as the plane’s top speed increased, it was capable of pulling maneuvers that could prove hazardous to pilots. Above 4g turns where a pilot without a g-suit was partially blacked out, the stick reversal could be harsh, but the worst of its effects were eliminated by a 20lb bobweight that was incorporated into the control system later on (Dean 350, 349).

The plane’s stall characteristics were mixed, but mostly mild. A one g stall in a clean aircraft was characterized by a roll to the right which came on after rudder buffering and aileron snatching, and was easily recovered from. Pilots were generally positive about the stall warning and recovery characteristics. However, its accelerated stall behavior proved to be far less universally understood. Some pilots claimed an easy recovery after ample warning, and others claimed it came on suddenly and viciously. Its low drag wings would contribute partly to this, as with its lack of air flow disturbances, stalls could come on without much warning. In the event of a spin, recovery was achieved by throttling back and pulling up while directing the rudder in the opposite direction of the spin. A spin could be serious trouble as a typical recovery resulted in a loss of about 9,000 ft in altitude (Dean 351, 352; P-51B flight manual 80).

While the plane was certainly very capable in regards to its maneuverability, pilots would have to take great caution when performing maneuvers of any kind when the fuselage tank still contained fuel. When the 85 gallon tank still contained fuel, the plane’s center of gravity shifted considerably and induced severe longitudinal instability. Hard maneuvers with any considerable volume of fuel still in the tank would result in a stick reversal that would require the pilot to brace themselves against the movement of the stick. Failing to do so would result in a loss of control or a further tightening of the turn which could result in a high speed stall or even structural failure (Dean 347, 348). Both RAF and USAAF manuals would ban aerobatics with roughly forty or more gallons of fuel in the tank, and suggested caution once it had been reduced to 25 gallons (Pilot’s Training Manual 68, Pilots Notes 30). In service this issue was one that rarely affected the plane’s effectiveness in combat, as the long range tank was the first to be used on long patrols and escort missions and thus typically contained little or no fuel when contact with enemy aircraft was made.

On early and mid production P-51B’s, pilots would also have to be cautious of high speed snapping brought on by the aforementioned longitudinal instability while they were conducting rolls. Pilots caught unaware were often injured during this violent jolt, and rolls were restricted accordingly. The addition of a fin extension for the vertical stabilizer and reverse rudder boost tabs would largely solve this issue, and the restrictions were lifted on suitably modified aircraft (Dean 350).

Perhaps where the aircraft shined the brightest were its dive characteristics, which were achieved as a result of its low drag wings and fuselage. These granted it excellent acceleration and a higher critical mach number than most of its contemporaries. Due to the changes in air flow across an aircraft’s wings as a plane approaches the sound barrier, most aircraft would experience buffeting, and a loss of control along and total loss of lifting forces. This change in flight characteristics that results in this loss of control is known as compressibility, a phenomenon that occurs when an aircraft exceeds the speed of its critical mach number.

A visual explanation of compressibility from the P-51B’s pilot training manual, the disturbed airflow results in a loss of lifting forces on the wings and control surfaces. The P-51’s wings mitigated the worst of its effects until much higher speeds. [Pilot’s training manual]
Thanks to its laminar flow airfoil, the P-51 was almost unique in its ability to remain controllable at otherwise unheard of speeds. However, in a high speed dive the P-51 would eventually experience compressibility and a pilot needed to be aware of the changing characteristics of their aircraft. In the P-51 this would first be felt through a ‘nibbling’ at the controls, afterwards by the stick ‘walking’ back and forth, and lastly by the aircraft pitching up and down with motions that grew more violent as the aircraft picked up speed (Pilot’s Training Manual 74, 75). On earlier models that lacked the vertical stabilizer extension, there was also directional instability that occurred at high speed, which required rudder correction or the plane could be sent into a spin. However with the later modifications the plane was nothing less than astounding. In diving tests from 35,000ft, pilots were able to reach mach .83 while retaining control of the aircraft, and despite the violent shaking and buffeting of the aircraft, were able to recover from the dive. In more practical conditions, control characteristics would remain normal until the aircraft was between .72 and .74 mach, after which the plane would experience escalating tuck-under, or a tendency to pull downwards airspeed increased. The maximum permissible dive speed was set at 505 mph IAS below 9000 ft, and 300 mph IAS at 35,000 ft, TAS being 539 mph (Mach .81). The maximum permissible engine RPM in dives was 3300 (Dean 341, 342, 343). Overall, the P-51B proved to be phenomenal in a dive, with only the British Hawker Tempest gaining a slight lead in tests, it being another aircraft equipped with laminar flow airfoils (Ethell 62).

Its take-off procedure was fairly typical of contemporary US fighters and required a strong right rudder deflection during take off to counteract the powerful torque from its engine. Its best climb out speed was between 160 to 170 mph IAS, which was quickly achieved after its flaps and landing gear had been retracted (Dean 341). Landing was somewhat more challenging, as the 140 mph IAS glide slope offered poor forward visibility, and little was improved as the plane came in to land at about 90 mph. It was thus fairly common for combat pilots to make tail up, level landings in order to have a better view of the landing strip before touching down. Its widely spaced gear and wide tire tread otherwise made the landing fairly easy.

While the P-51B’s possessed some truly phenomenal flight characteristics, the same cannot be said for the canopy. In US Navy evaluations the ‘birdcage’ canopy was found to result in poor all-around vision, most notably fore and aft. It was also fairly restrictive and made turning to view behind the aircraft more difficult (Dean 353). The frame itself could also not be opened on take off or landing and thus proved to be of some annoyance to pilots. This would later be solved with the addition of the ‘Malcom Hood’ which provided excellent visibility and was far less confining. The rest of the cockpit was judged to be satisfactory and capable of accommodating pilots of varying stature.

The ‘birdcage’ was unpopular as it was quite restrictive in terms of visibility, and it could not be kept open on the landing approach or takeoff. [Pilot’s Training Manual]
Its armament however, was distinctly lacking and fairly unreliable. It’s armament of four .50 caliber AN/M2’s was considerably lighter than most US fighters of the time and were installed in such a way that the ammunition links were prone to deformation in high-g maneuvers. It was not uncommon for P-51B/C’s to return from their missions with several guns malfunctioning as a result of failures to feed or extract. As a gun platform, its qualities were judged as roughly the same as the P-40, and below those of the P-38 and P-47 (Dean 353).

Comparisons with American Fighter Aircraft: Early to Mid 1944

Entering service alongside the P-47 and P-38, the new P-51’s would compare very well. When it came to the P-47D, equipped with R-2800-63’s, these aircraft were in some ways complementary, and excelled in areas the other did not. Thanks to its powerful turbosupercharger, the P-47 would retain the power needed to outperform the P-51 above 25,000ft, but was significantly slower at lower altitudes. The P-47 was also less vulnerable to ground fire and thus better suited for ground attack missions. The P-51B however, outstripped the P-47D in rate of climb, linear speed, acceleration at altitudes below roughly 30,000ft, and dive performance (Ethell 70; Marshall & Ford 526). Ergonomically speaking, the P-51B was the superior aircraft, as the turbosupercharger controls of the P-47D added to the workload of the pilot.

The P-47’s Turbosupercharged R-2800 engine provided unparalleled performance above 30k feet, and it’s durability made it ideal for fighter bomber missions. It was fairly lacking in its rate of climb and acceleration at low to medium altitudes. [National Archive]
When it came to escorting bombers, the P-47D and P-51B were the most effective tools at the USAAF’s disposal. Both aircraft performed superbly at and above the altitudes the bombers typically flew at, though the P-51B would prove the more vital as it could travel significantly further. By late spring 1944, external fuel tanks had been introduced that extended the P-47’s escort radius across most of Germany, however, by this time the P-51B was capable of accompanying bombers beyond Poland (Marshal & Ford 516). While the shorter range of this aircraft was often used to excuse the high bomber losses during earlier campaigns, the fact is that had they been supplied with the proper external fuel tanks, they would have been capable of deep incursions into German airspace months before the P-51 entered service.

The P-38 experienced serious reliability and performance issues due to the extremely low temperatures encountered at high altitude over Northern Europe. Its poor high altitude dive performance was also widely known, and exploited by Luftwaffe pilots. [National Archives]
The older P-38J Lightning would not stack up quite as favorably against the new Mustang. While the P-38J possessed a better climb rate and acceleration, it was out-stripped in linear speed by the P-51B at all altitudes, and possessed a very low critical mach number which meant that virtually any opponent at high altitude could escape by diving away. To make matters worse, a number of technical and operational issues spelled trouble for these aircraft in the colder Northern European climate. These issues, compounded by the extremely poor cockpit and canopy of the P-38, saw Lightning squadrons fall behind Thunderbolt and Mustang squadrons in victory credits (Marshall & Ford 439, 516; Ethell 70).

While the P-38J would receive external fuel tanks that would allow it to travel to Berlin and back, it was held back by a number of factors that severely reduced its combat effectiveness. In the European Theater of Operations, the P-51B would present a clear and general improvement over the P-38s, which saw more success in other theaters with conditions that they were better suited to, namely the Mediterranean and Pacific.

German Fighter Comparison: Early to Mid 1944

Entering service near the end of 1943, the P-51B compared very well to the German Fw 190As and Bf 109Gs in service at that time. The typical Bf 109 encountered through the first half of 1944 was the Bf 109G-6 series, which possessed better firepower than those that preceded it, but was heavier, and initially slower for it. These planes were equipped with either the Daimler-Benz DB 605A, or the high altitude, DB 605AS engines, both of which were later equipped with MW-50 boost systems. In all cases the P-51B possessed the superior linear speed, but in the case of MW-50 equipped aircraft, the Mustang had a slightly lower climb rate at low to medium altitude (Marshall & Ford 526, 523; P-51 flight tests). Without the boost system, which came into widespread use in the summer of 1944, the Bf 109G-6 was considerably slower and had a clear disadvantage in top speed and climb rate at all altitudes. The disparity with the high altitude model was much narrower, though the P-51 still held an edge.

The Bf 109G-6 was the most common Luftwaffe fighter encountered by the P-51. Later versions boasted considerably higher engine power thanks to the MW50 boost system; they did not compare well to many western allied fighters prior to this. Here one prepares for a fighter bomber sortie. [Asisbiz]
When it came to maneuverability, both aircraft had their own advantages, with the Bf 109 having better low speed handling and the P-51 having the advantage at high speed. The dive performance of the P-51B was far superior even at lower altitudes as the Bf 109 experienced stiffening of the elevator at high speed.

Visibility the Bf 109 was more or less on the same level of the standard ‘birdcage’ P-51B, and this would largely remain the case, as both planes would be re-equipped with improved canopies that offered better visibility. However, the cockpit of the P-51 was considerably more spacious and was further improved by the Malcolm hood. The Bf 109’s greatest strength was that it was equipped with an automatic RPM governor and mixture control that took a great deal of work off the pilot.

In terms of armament, both aircraft were comparable, with an unmodified Bf 109G-6 possessing a pair of 13mm machine guns and either a 20 or 30mm cannon, which fired through the propeller hub. Of the two, the 30mm was far less common.

Overall, the Bf 109G-6 was a somewhat dated fighter, one that had its advantages, but was  generally outclassed by the new Mustang. However, upgrades like water-methanol injection, an improved vertical stabilizer, and a new canopy helped keep the aircraft competitive and staved off obsolescence. The much refined ‘Kurfurst’ series would match P-51 performance in a number of areas, but its introduction was well after the Luftwaffe had lost control of German airspace.

The P-51B would face several models of the Fw 190A, with the most up to date being the A-8. The P-51B would have considerable linear speed, climb, and high altitude dive advantages over the earlier models. The Fw 190A-8 would have the benefit of a significant boost in power to its BMW 801D-2 engine, first by means of a fuel injection system, and in the summer of 1944, they were judged robust enough to be run at higher manifold pressures and had their supercharger boost regulators overridden. These modifications allowed the engine to produce significantly more power and increased the aircraft’s top speed at all altitudes (Douglass 344). In terms of top speed, this put these two aircraft on closer footing at low altitude, and ahead of the other two American fighters. It was, however, nowhere close to offsetting the general disparities at higher altitudes. The excellent defensive characteristics of the aircraft helped to offset some of its disadvantages against the P-51, as the Fw 190A held the best roll rate in the theater, solid dive characteristics, and good rearward visibility.

The Fw 190A’s were completely outclassed at altitude by the P-51B, owing to their relatively low full throttle height. They would however, be on somewhat closer footing at lower altitudes and could hold their own against the other two American fighters. [Asisbiz]
In terms of armament it was no contest, as the earlier A-6’s and A-7’s possessed a pair of either 7.92mm or 13mm machineguns respectively, and a pair of 20mm cannons. This was increased to two pairs on the Fw 190A-8. In regards to ergonomics the Fw 190A was excellent, with good visibility, clean instrumentation, and an advanced engine control system which handled RPM, manifold pressure, and mixture through the use of a single, integrated electro-mechanical computer. Its controls too were tight and responsive, if a little heavy at speed, thanks to its push rod control system. However, as was also the case with the Bf 109, its cockpit was comparatively cramped compared to the P-51.

Subsequent models of both these aircraft, the most numerous being the Bf 109G-14 and the Fw 190D-9, would largely eliminate the performance disparity at low altitude. However, at medium to high altitudes, the P-51 would still enjoy a considerable edge in top speed, dive performance, and high speed maneuverability. Only later Bf 109G’s with enlarged superchargers and better high altitude performance were close to closing the gap, with the K-4 series finally achieving high altitude parity near the very end of the war.


The Bf 109G-14 and the Fw 190D-9 would enter service in the Autumn and Winter of 1944, though they would not entirely replace their predecessors by the end of the war. [Largescaleplanes, Asisbiz]
The Me 262 presented a much greater threat in the air for obvious reasons. The jet fighter possessed a top speed roughly 100 miles per hour faster than the P-51 and was the only Luftwaffe fighter capable of following it into a dive. It was, however, considerably lacking in acceleration, which presented itself most dangerously on take off and on the landing approach. While the high top speed of the jets meant that they could disengage safely from most confrontations, they were helpless if caught near taking off or landing. Thus the general strategy for defeating these aircraft was to catch them as they were returning to their bases, where Allied fighters would await them. This is not to say this was easy, as their airfields were well defended by some of the best flak units available to the Luftwaffe and they would eventually have their own dedicated fighter cover (Ethell 97, 98). Higher up the jet could prove a deadly opponent as when flown well, it was extremely difficult to catch and an experienced pilot had control over most engagements.

The Me 262 was a world first, and had many USAAF planners concerned. On paper it had the ability to wreak untold havoc on allied bomber formations, but its technical limitations and the general poor state of the Luftwaffe late in the war prevented it from operating in numbers large enough to make a major impact. [Asisbiz]
In any case, encounters with the new jet fighters were fairly uncommon as they were constrained by operational restrictions owing to the temperamental nature of the new turbojet engines and the lack of a dedicated trainer for the aircraft until late 1944. They would not be seen flying against the Allies in appreciable numbers until the late autumn of that year.

Building the P-51B & C

The P-51B’s and C’s were built at plants in Inglewood, California, and Dallas, Texas, respectively. The distinction exists due to the differences in manufacturing between these two facilities, but these are functionally the same aircraft. With the exception of the earliest model, the P-51B-1, which had a different aileron design, their components were interchangeable. The main production models were equipped with the Packard V-1650-7 engine. Deliveries of these models began in February of 1944 (Marshall & Ford 253)

Production of this aircraft was complicated greatly by the breakneck pace of its procurement, which saw massive orders placed before its prototype had completed testing. As such, the aircraft that left the factories differed considerably even when they were built mere weeks apart. While all WWII fighters underwent constant modification, the level and rate of changes made to the P-51B and C were extensive and rapid. In addition to minimal changes, like changing the pilot’s seat from a wooden one to a magnesium one, in a matter of weeks the P-51B would receive an additional fuselage fuel tank, an extension to its vertical stabilizer and a rudder anti-balance tab, and an elevator control system which made use of a 20lb bob weight (Dean 329). These features would constitute a considerable challenge to work into the design without compromising the pace of production for an aircraft that USAAF planners wanted in as great quantity in the shortest possible time.

The Inglewood P-51 production line. [North American Aviation]
This challenge would highlight both the greatest strengths and weaknesses in US aircraft manufacturing. Most aircraft factories in the US operated by building large batches where the design would be frozen to allow faster construction. Modifying the design meant changes to the production line, which meant slowing down or stopping. US factories operated at batch sizes of up to 1,500, compared to the British Supermarine Spitfire’s production lines which operated at or below 500. The compromise was the modification center, to which “finished” aircraft would be delivered to be fitted out to new modifications. In practice, this system was extremely inefficient and saw quality control drop significantly. It also proved to be a highly inefficient use of labor, and could represent between 25 to 50% of the total labor required to complete an aircraft. Quality control also dropped considerably as the modification center was primed to try and deliver aircraft as quickly as possible (Zeitlin 55, 59). Lastly, the centers saw a great deal of wastage of material, accumulating a much larger proportion of metal scrap from rushed fittings, and ruined parts than the production lines (O’Leary 142). The USAAF would have its Mustangs, but only at a considerable cost and of initial questionable quality.

In the end they were successful in that they delivered the P-51B in great quantities despite the rushed pace of procurement, development, and production. However, it certainly contributed to the severe teething issues experienced by the aircraft that would see it briefly grounded in March of 1944 and would trouble it for weeks later.

In all, 1,988 P-51Bs were built with the first leaving the production lines, at a very low initial rate, in the summer of 1943 with the first deliveries taking place in August, with a further 1,750 P-51C’s being built. Production of both types declined as the P-51D production began in January of 1944, with the last P-51B’s leaving Inglewood in March and P-51C production continuing for several more weeks (Dean 321).

Construction

Wings

The wing group of the P-51 was composed of each wing, bolted together at the centerline. Each wing was of a cantilever stressed skin construction and consisted of a main panel, the wingtip, the flap, and the aileron. The main panel was built up around a main forward spar and a rear spar, to which twenty one pressed ribs were attached. These spars were spliced together roughly around half their length. A self-sealing 90 gallon fuel tank was fitted at the inboard section and a bay for its .50 caliber machine guns and ammunition was found near the center. The ailerons were of a fairly heavy construction, being all metal and supported by two spars and twelve flanged ribs. They were aerodynamically balanced by a diaphragm attached to the forward edge of the aileron and sealed to the rear spar by a fabric strip. These were controlled by means of a cable, as were all of the control surfaces of this aircraft. These were equipped with trim tabs and were adjustable in flight. The flaps were all metal plain flaps that were hinged on three sealed ball bearings and were hydraulically actuated.

[Legends in their time]
The landing gear was hydraulically actuated with a fully retractable tail wheel. The main landing gear were fixed to the wings by a cast magnesium supports and were equipped with multiple disc brakes connected to the hydraulic cylinder by metal tubing. The wheels were 27 inches in diameter and possessed a fairly wide tread, which helped to give the P-51 excellent ground handling.

The wings of the P-51 were designed to achieve laminar flow and used a NAA/NACA 45-100 series airfoil. It would fall short of true laminar flow as even extremely minor surface imperfections resulted in airflow disruptions that made laminar flow impossible. However, these were among the most aerodynamically advanced wings used by any fighter during the Second World War, providing extremely low drag and excellent high altitude dive performance.

Fuselage

[Legends in their time]
The fuselage was composed of two main sections, both of which had a semi-monocoque construction. The main section was formed by four extruded longerons, around which the intermediate frames and stringers were connected. The upper longerons were extruded H-sections which extended from the sheet metal firewall and tapered into a T-section. The lower longerons, consisting of an H-section and U-channel, extended the full length of the main fuselage. This entire unit was made up of eight assemblies which were riveted and bolted together, these being the firewall, turnover, truss, upper deck, left and right side panels, radio shelf, web assembly, and the radiator air scoop.

The main fuselage section also contained the cockpit, the windshield being composed of a center pane of bullet resistant five pane laminated glass, with two Plexiglas windows to either side. The canopy was either a metal framed Plexiglas ‘bird cage’, or a Malcom Hood. The birdcage had panels that opened outward on the top and port side. The hood slid back across the rear of the canopy. Behind the pilot were lucite windows which enclosed the radio space. A relief tube was installed and stored beneath the seat, and proved quite useful considering the long flights that this aircraft commonly made.

Early P-51B instrumentation. [Legends in their own Time]
The rear section was comparatively simple, composed of two longerons, a shelf, five formers, and three solid bulkheads. The fuselage, as with the rest of the aircraft, was skinned in Alclad. This section was reinforced after structural failures during high speed rolls in early models.

Tail Section

The tail section was affixed to the rear fuselage and consisted of the horizontal stabilizer, elevators, fin, vertical stabilizer, and the rudder. The horizontal stabilizer was a one piece assembly supported by two spars, fixed to the fuselage by four bolts, and through which the vertical stabilizer was attached. The elevators consisted of a front spar with eighteen flanged ribs, and was initially fabric skinned with Alclad leading edges before it was later entirely metal skinned. These were fastened with five sealed ball bearing hinges and each had an adjustable trim tab.

The vertical stabilizer was supported by two spars along with four ribs and a detachable tip. Extensions to the vertical stabilizer by means of a fin were added to P-51B/C’s to correct for longitudinal stability issues with a full fuselage fuel tank, and to correct certain undesirable characteristics when the aircraft was put through a roll. The rudder was fitted at the rear of the stabilizer and was supported by a single spar to which twenty flanged ribs were attached. Much of the rudder was skinned with mercerized cotton, save for the reverse edge. The rudder was fitted with a trim tab and aerodynamically balanced by means of a 16.6 lb lead weight at the tip.

Engine Section

The engine section consisted of the engine mounting and external cowl components and was bolted to the firewall. The cowl consisted of a frame made of Alclad beams to which the cowl panels fastened. This frame acts as a cradle for the engine which is mounted by a bracket through anti-vibration units. The entire section is designed to facilitate easy access to the engine through panels, and the engine mount allows for the rapid removal of the Packard engine.

[Legends in their time]

Engine

The early models of the P-51B used a Packard V-1650-3, with this engine being replaced on the production line in February of 1944 with the Packard V-1650-7. These are largely the same engine, though their superchargers were geared for optimal performance at different altitudes and thus have different maximum outputs. The 1650-3 was designed specifically for high altitude use and gave the P-51B/C a full throttle height of 29,000 feet, the 1650-7 was geared to achieve a higher engine output at a FTH of 21,400 feet (Marshall & Ford 253).

These engines had a bore of 5.40 inches, a stroke of 6 inches, a displacement of 1,649 cubic inches, a compression ratio of 6.0:1, a width of 30 inches, a height of 41.6 inches, length 87.1 inches, a frontal area of 5.9 sq. ft, and a weight of 1690 lbs. They differed in that the -3 supercharger ratios of 6.391:1 and 8.095:1, and those of the -7 were 5.80:1 and 7.35:1 (Wilkinson 125, 127). They were both fitted with a four blade Hamilton-Standard 24D50-65 or -87 hydropneumatic propeller with aluminum blades of a diameter of 11 feet and 2 inches. These blades were either 6547-6, 6547A-6, or 6523A-24 types. The engine exhaust stacks were of a stainless steel construction which had a removable exhaust shroud to keep heat from the spark plugs and to reduce drag.

Packard V-1650-7 [Pilot’s training manual, Smithsonian]
Both engines used a two stage, two speed supercharger and was equipped with an aftercooler. The supercharger was automatically controlled and governed by the air pressure at the carburetor intake, which was found just below the prop spinner. The controls for the engine were conventional, requiring manual throttle and rpm adjustments.

Radiator and Cooling Systems

The engine was cooled by two separate systems, one dedicated to the engine, and the other cooled the supercharged fuel-air mixture. Both of these systems were connected through the main radiator matrix within the air scoop below the main fuselage, with the coolant flow maintained by an engine driven pump. A smaller radiator for the oil cooler was placed below and ahead of the radiator matrix for the engine and aftercooler. The radiator setup was designed to make use of the Meredith effect, which in practical terms meant that the heated air flow out of the radiator produced thrust which counteracted a large percentage of the drag incurred by the scoop. The outlet for the radiator was automatically controlled. This design was able to reduce net drag upwards of 90% and was one of the most important features which allowed the aircraft to achieve such a high top speed (Marshall & Ford 510).

[Legends in their time]
The hoses for the radiator which extended through roughly two thirds of the aircraft, and the unarmored radiator, which sat at the bottom center of the aircraft, constituted the most vulnerable part of the aircraft’s design. These made the aircraft fairly vulnerable to ground fire, as the high cooling requirements of the Packard Merlin engine meant that a failure of the cooling system wouldn’t take long to put the aircraft out of action.

Fuel System

The initial models of the P-51B possessed only two 92 gallon wing fuel tanks with an 85 gallon fuselage fuel tank being included later through modification kits and was eventually incorporated into the production line. The Mustang was also capable of carrying two external fuel tanks by means of wing mounts. Fuel was drawn only from individual fuel tanks, requiring the pilot to manage up to five individual sources of fuel throughout longer flights (Pilot’s Training Manual 26).

[Pilot’s Training Manual]
The inclusion of the 85 gallon fuselage tank would introduce new challenges, as the shift in weight caused by a full tank introduced severe longitudinal instability. For this reason this tank was the first to be consumed. The combined tankage was 269 gallons.

Armament and Armor

P-51B’s were equipped with four .50 caliber AN/M2 machine guns. Each inboard gun was supplied with up to 250 rounds, with the outboard weapons having 350 each. These guns were mounted at roughly 45 degree angles within the wing, which caused severe cycling issues when the guns were fired while the aircraft was pulling hard maneuvers. These issues were lessened with the addition of electric boost motors for the ammunition feed, but were not completely solved until the subsequent P-51D model. The guns were electrically heated to prevent them from locking up at high altitudes. These aircraft were typically equipped with the N-3B reflector gunsight, with later aircraft receiving K-14 gyroscopic gunsights.

[National Archives]
Wing pylons allowed the aircraft to carry a payload of up to 500 pounds at either side, being either external fuel tanks or bombs. These aircraft could be made to carry rockets by means of field modification kits. Armor plates were placed ahead of the radiator header tank, at the engine fire wall, and behind the pilot.

(Dean 355-376)

Conclusion

It would take a considerable effort to develop the P-51B from its Allison engined predecessors, and even greater hurdles would have to be overcome to produce them in the quantities needed. In the end, both were achieved and the P-51B would enter large-scale operation in the Spring of 1944. In spite of its harsh teething issues, it would become among the most decisive weapons of the Second World War. With its incredible range and medium and high altitude performance, the aircraft would prove instrumental in establishing air superiority over Western Europe prior to Operation Overlord, and contesting the skies over Germany itself.

P-51B production was switched over to the D model at Inglewood in March of 1944, but the aircraft would remain in service in large numbers through the end of the war. [National Archives]
Its design, while not revolutionary, was thoroughly advanced and represented a considerable leap in aerodynamics and airframe design. The P-51B would however, be only a starting point for the Packard Merlin Mustangs, as further refinements would result in the iconic, and much more widely produced P-51D.

Specifications

P-51B/C ( with Fuselage tank) Specification
Engine  Packard Merlin V-1650-3, V-1650-7
Engine Output [V-1650-7] 1630 hp [1720 hp]
Maximum Escort Fighter Weight 11,150 lbs (2x108gal external)
Gross Weight 9,681 lbs
Empty weight 6,988 lbs
Maximum Range [External Fuel] 1350 miles [2150 miles]
Combat radius [External Fuel] 375 miles [750 miles]
Maximum speed (V-1650-7) 444 mph (75″ Hg) at 20600ft
Armament  4x .50 cal M2 machine guns, 1200 rounds of ammunition
Crew Pilot
Length 32′ 2
Height (tail down) 12’8
Wingspan 37.03′
Wing Area 235.75 sq.ft

 

P-51B/C ( with Fuselage tank) Specification
Engine  Packard Merlin V-1650-3, V-1650-7
Engine Output [V-1650-7] 1630 hp [1720 hp]
Maximum Escort Fighter Weight 5058 kg (2×409 liters external)
Gross Weight 4391 kg
Empty weight 3169 kg 
Maximum Range [External Fuel] 2172 km [3460 km]
Combat radius [External Fuel] 603 km [1207 km]
Maximum speed (V-1650-7) 714 km/h (1905mm Hg) at 6279 m
Armament  4x 12.7mm M2 machine guns, 1200 rounds of ammunition
Crew Pilot
Length 9.80 m
Height (tail down) 3.86 m
Wingspan 11.29 m
Wing Area 21.9 sq.m

(Dean, Performance Tests on P-38J, P-47D and P-51B Airplanes Tested with 44-1 Fuel., Marshall & Ford)

Maximum Level Speed Speed at 67″ Hg, 3000 RPM 75″ Hg, 3000 RPM No wing racks, 75″ Hg, 3000 RPM
Sea level 364 mph 380 mph 388 mph
Critical altitude low blower 408 mph at 10400 ft 411 mph at 2300 ft 422 mph at 7400ft
Critical altitude high blower 426 mph at 23900 ft 431 mph at 20600ft 444 mph at 20600ft
Aircraft Specification Gross weight 9680lbs, P-51B-15  (V-1650-7)

*A note on fuels: The 75″ of manifold pressure figure represents the high end of performance using 150 octane fuels, these were typically only available to P-51 squadrons based in England.

Climb rate 67″, 3000 RPM 75″ Hg, 3000 RPM
Maximum at low blower 3,920 ft/min at 5600 ft 4,380 ft/min 2,300 ft
Maximum at high blower 3,170 ft/min at 19,200 ft 3,700 ft/min at 15,600 ft
Aircraft Specification Gross weight 9680lbs, P-51B-15

 

Maximum Level Speed Speed at 1701 mm Hg, 3000 RPM 1905mm Hg, 3000 RPM No wing racks, 1905mm Hg, 3000 RPM
Sea level 586 km/h 611 km/h 624 km/h
Critical altitude low blower 656 km/h at 3169 m 661 km/h at 701 m 679 km/h at 2255 m
Critical altitude high blower 685 km/h at 7284 m 693 km/h at 6278 m 714 km/h at 6278 m
Aircraft Specification Gross weight 4390 kg, P-51B-15 (V-1650-7)

 

Climb rate 1701 mm Hg, 3000 RPM 1905 Hg, 3000 RPM
Maximum at low blower 1194  meter/minute at 1707 m 1335 meter/minute 701 m
Maximum at high blower 966 meter/minute at 5852 m 1128 meter/minute at 4755 m
Aircraft Specification Gross weight 4390 kg, P-51B-15

(Performance Tests on P-38J, P-47D and P-51B Airplanes Tested with 44-1 Fuel.)

P-51 Variants through P-51D

North American USAAF RAF Engine Armament No. Built Additional Notes. First delivery
NA-73X Allison 1 Prototype. October 1940
NA-73, -83 XP-51 Mustang Mk I Allison 2x .50 cal MG, 4x .30 cal MG 622 RAF, export. August 1941
NA-91 P-51 Mustang Mk Ia Allison 4x 20mm cannons 150 ‘Plain P-51’. July 1942
NA-97 A-36A Allison 6x .50 cal MG, bombs 500 Dive Bomber. October 1942
NA-99 P-51A Mustang Mk II Allison 4x .50 cal MG 310 March 1943
NA-101 XP-51B Packard 4x .50 cal MG 2 (converted) P-51B prototype
NA-102, -104 P-51B Mustang Mk III Packard 4x .50 cal MG 1988 Inglewood production. Summer 1943
NA-101, -103 P-51C Mustang Mk IIIB Packard 4x .50 cal MG 1750 Dallas production. August 1943
NA-106 (through -124) P-51D Mustang Mk IV Packard 6x .50 Cal MG +8000 Bubble canopy. January 1944

(Dean 321)

P-51B & C Variants

P-51B & C Variants Notes Serial No.’s
P-51B-1-NA Earliest production model, steel aileron diaphragms, two point aileron attachment.  43-12093 to 12492.
P-51B-5-NA Three attachment points per aileron, non-magnetic diaphragm.  43-6313 to 6352, 43-6353 to 6752, 43-6753 to 7112.
P-51B-7-NA B-1s and 5s which received a new fuselage fuel tank carried this designation. Aircraft often carried prior designation in practice. Converted aircraft.
P-51B-10-NA Production model with fuselage tank.  43-7113 to 7202, 42-106429 to 106538, 42-106541 to 106738.
P-51B-15-NA Engine changed to Packard V-1650-7 (previous models were converted to this engine via supercharger kits).  42-106739 to 106908, 42-106909 to 106978, 43-24752 to 106738.
P-51C-1-NT Same as P-51B-5-NA.  42-102979 to 103328
P-51C-2-NT C-1s which received a new fuselage fuel tank carried this designation. Aircraft often used prior designation in practice. Converted aircraft.
P-51C-5-NT Same as P-51B-15-NA. 42-103329 to 103378, 42-103379 to 103778.
P-51-C-10-NT Production model with stabilizing fin extension. 42-10818 to 103978, 43-24902 to 25251, 44-10753 to 10782, 44-10818 to 10852, 44-10859 to 11036, 44-11123 to 11152.
P-51C-11-NT Production model. 44-10783 to 10817, 44-10853 to 10858,44-11037 to 11122.
F-6C Photoreconnaissance. Converted Aircraft.
TP-51C Dual control trainer. Converted Aircraft.

(Marshall & Ford, O’Leary)

Video

Gallery

Illustrations by Ed Jackson

XP-51B, 312093. The XP-51B’s were a pair of earlier Mustangs converted to use the Packard V-1650-3. Their cooling systems would prove the most troublesome, though the general teething issues these aircraft experienced were harsh and varied.
P-51B-7-NA 43-6913 ‘Shangri-La’. Debden, UK 1944. Debden ,UK 1944. This aircraft was flown by Capt. Don Gentile of the 4th Fighter Group, one of the unit’s leading aces.
P-51B. 325th Fighter Group. Poltava, USSR 1944. The 325th was among the units that participated in Operation Frantic, where they supported a series of USAAF raids launched from within the Soviet Union during the summer and fall of 1944.
P-51B-5-NA, 43-12214 ‘Rebel Queen’. Debden, UK 1944. This aircraft was flown by Col. Don Blakeslee, Commanding Officer of the 4th Fighter Group. This aircraft is an early production P-51B which had been equipped with a Malcolm Hood bubble canopy, this modification greatly improved visibility.
P-51C-10-NT ‘By Request’. Ramitelli, Italy 1944. This aircraft was flown by Col. Benjamin Davis, Commanding Officer of the 332nd Fighter Group. This is a late model which has been fitted with a fin fillet, extending from the vertical stabilizer. This addition greatly improved the aircraft’s stability in rolls and high speed dives.

B-17’s accompanied by a P-51B over England, March 1945.[National Archives]
A collection of P-51’s accompany a flight of B-24s of the 8th Air Force, near England. 1944. [National Archives]
The Malcom Hood bubble canopy would offer pilot’s great visibility compared to the ‘birdcage’. [National Archives]
The P-51A can be easily differentiated from its merlin powered counterpart by the tube shaped carburetor intake over the nose. [wikimedia]
Though most P-51B’s would be sent to Europe, some would serve in the China-Burma-India theater. Here a Mustang cruises alongside a C-47. [National Archives]
Ground crew pose alongside one of their planes. [National Archives]
A P-51B in the CBI theater is cleaned. This plane has had its exhaust fairing removed, a fairly common modification made in the field which some pilots believed cut down on drag. [National Archives]
A P-51B comes in to land, the wide tire tread and wheel base of these planes helped give these planes good landing and ground handling. [National Archives]
Ground crew pose with one of their planes, the tail fin extension as equipped to this plane helped alleviate some of the aircraft’s less desirable characteristics when it was rolled. [National Archives]
Among the challenges caused by segregation for the 332nd were personnel shortages. The only available training facility at Tuskegee struggled to turn out enough pilots and ground crew to support the segregated squadrons. Mechanics and armorers were among the most affected, especially when the fighter group rapidly transitioned from P-39’s, P-47’s, and P-40’s to P-51’s over the late spring and summer of 1944. [National Archive]
P-51B’s of the 325th Fighter group accompany bombers on their way to the Soviet Union during Operation Frantic. [National Archives]
The success of Operation Overlord saw the redeployment of many USAAF units to the continent. These P-51’s of the 9th AF were the first to be deployed to France. [National Archives]
The F-6C was a photo-reconnaissance variant that had a camera installed in the fuselage, the lens cover for which sits here just behind the radiator scoop. This model was credited with the last kill in the ETO, after downing a Fw 190 on May 8 1945 (Dean 339). [Wikimedia]

Credits

  • Written by Henry H.
  • Edited by  Ed Jackson & Henry H.
  • Illustrations by Ed Jackson

Sources

Primary:

  • Flight Tests On The North American P-51B-15 Airplane, AAF NO. 43-24777, 1944.
  • Preliminary Results of Performance Tests on a P-51B Airplane with 44-1 Fuel P-51B-5-NA, V-1650-7 Engine. 1944.
  • P-51B-15-NA 43-24777 (Packard Merlin V-1650-7) Performance Tests on P-38J, P-47D and P-51B Airplanes Tested with 44-1 Fuel. (GRADE 104/150). 15 May, 1944.
  • Matthews, H. F. Elimination Of Rumble From The Cooling Ducts Of A Single-Engine Pursuit Airplane. NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS. 1943.
  • Messerschmitt A.G. Augsburg. (1944). Leistungen Me 109 G-14/U4 mit Db 605 Am u. Asm. 1944.
  • Pilot Training Manual for the Mustang. United States Army Air Force, 1943.
  • Pilot’s Flight Operating Instructions P-51B-1 Airplane. Evansville, Indiana: United States Army Air Force, 1943.
  • Pilot’s Notes for Mustang III Packard Merlin V-1650-3 Engine. Air Council, 1944.
  • Wilkinson, Paul. Aircraft Engines of the World. 1944.
  • The United States Strategic Bombing Survey: Over-All Report (European War). U.S. Govt. Printing Office, 1945.

Secondary:

  • Bucholtz, Chris. 332Nd Fighter Group: Tuskegee Airmen. Oxford: Osprey Publishing, 2007.
  • Bucholtz, Chris. 4Th Fighter Group “Debden Eagles”. Oxford: Osprey Publishing, 2008.
  • O’Leary, Micheal. Building the P-51 Mustang the Story of Manufacturing North American’s Legendary WWII Fighter in Original Photos. Specialty Pr Pub & Wholesalers, 2011.
  • Dean, Francis H. America’s Hundred Thousand: the US Production Fighter Aircraft of World War II. Schiffer Publ., 1997.
  • Douglas, Calum E. Secret Horsepower Race: Second World War Fighter Aircraft Engine Development on the Western Front. TEMPEST, 2020.
  • Ethell, Jeffrey L. Mustang: A Documentary History of the P-51. London: Jane’s, 1981.
  • Haulman, Daniel L. Nine Myths about the Tuskegee Airmen. October 21, 2011.
  • Marshall, James William; Ford, Lowell. P-51B Mustang: The Bastard Stepchild that saved the Eighth air force. Bloomsbury Publishing Plc. 2020. (Electronic)
  • Moye, J. Todd. Freedom Flyers: The Tuskegee Airmen of World War II. New York, NY: Oxford University Press, 2012.
  • Overy, Richard James. The Bombing War: Europe 1939-1945. London: Penguin Books, 2014.