Germany (1943) Experimental Circular Wing Aircraft – 1 Prototype Built
The unusual Sack AS-6 circular-wing aircraft [falkeeins.blogspot.com]In the history of aviation there were many designers who had ambitious ideas and concepts for new designs, but never had the chance to bring their ideas to fruition. On the other hand, there were those who had radical or even completely impractical designs that did manage, at least to some extent, to be built. Germany had a fair share of such individuals, especially during the later stages of the Second World War. These designers may have proposed their projects out of desperation to save their country or in fear of being sent to the front. There were also those that were simply enthusiasts in aircraft development but lacked a better understanding of how aerodynamics actually work. One such person was Arthur Sack (1900-1964), who prior to the war came up with the idea of building a circular-wing aircraft known simply as the Sack AS-6.
History
Prior to the war, Germans were prohibited from developing and building military aircraft. The Germans simply bypassed this prohibition by instead focusing on gliders, but also on civilian aircraft which if needed would be quickly converted for military use and conducted secret experiments. They especially took great care in the development and investment of manned gliders, but also scale model-building competitions and organizations. While this may seem like a waste of time and money, it actually helped gain initial and valuable experience in aircraft development which proved vital for the later Luftwaffe.
One such model competition was the National Contest of Aero Models with combustion engines, held in late June 1939 at Leipzig-Mockau. Here, aviation enthusiast Arthur Sack presented his model of an unusually circular-wing-shaped aircraft named AS-1. It is sadly unclear why Sack pursued the design of such an unusual aircraft design. Due to engine problems, the AS-1 was unable to take off from the ground, so the small model had to be launched by hand instead. The Air Minister (Reichsluftfahrtministerium RLM) Ernst Udet, who was present at the event, seemed to be impressed with this design and advised Sack to continue its development.
Arthur Sack and his AS-1 model. [lvz.de]Thanks to financial support from the RLM, Sack was able to proceed with the development and even the construction of a few scale models, a process that lasted some three years. In 1943 he submitted a fully operational model SA-5 to the RLM. The presentation went well for Sack and the RLM commission provided the necessary funds for the construction of a fully operational prototype. Interestingly, at some point Sack came into contact with another unusual aircraft designer Dr. Alexander Lippisch. While not completely clear, it appears that Sack received some design tips from Lippisch, to better improved his work.
With the order secured, Sack initiated the construction of a prototype. He named this aircraft the AS-6 V1 (Versuchs – version). As he had no proper workshop to build the aircraft himself, the glider manufacturer Mitteldeutsche Metallwerke was tasked with this instead. The initial work for the assembly of the aircraft began in the autumn of 1943. It took nearly half a year to complete the working prototype. Interestingly, due to the general shortage of materials, the AS-6 was constructed by utilizing a considerable amount of salvaged components from other damaged aircraft. For example, the cockpit canopy and parts of the interior were taken from a Bf 109B. Once the prototype was ready, it was allocated to the Luftwaffe for initial tests in early 1944.
AS-6 side view. [lvz.de]
Technical Characteristics
A good view of the AS-6 internal wooden frame construction.[all-aero.com]The AS-6 was designed as an experimental prototype to test the idea of using circular-wing design. Sadly, this aircraft is quite obscure and poorly documented so not much is known about its overall design. It was a single-seater aircraft that was mostly built out of wood. It did not have a classical fuselage, instead, the majority of the aircraft consisted of two large circular wings. The internal design is more or less conventional with a wooden construction frame being covered with canvas. Two large elevators were installed on the rear of the wings. The tail assembly is a conventional design as well, consisting of one vertical stabilizer and two horizontal stabilizers.
The AS-6 rearview. The two elevators were too small, poorly designed, and did not provide adequate control during initially limited test flights. [all-aero.com]The AS-6 was powered by an Argus As 10C-3 engine, which ultimately proved to be inadequate [all-aero.com]The AS-6 was powered by a 240 hp Argus As 10C-3 engine driving a two-blade wooden propeller. The engine was housed in a metal frame, which was then bolted to the AS-6 fuselage. The engine was salvaged from a Bf 108 aircraft.
The cockpit canopy and its interior, as already mentioned, were taken from a Bf 109B. The cockpit was slightly elevated above the fuselage and provided the pilot with an excellent all-around view. The landing gear was also salvaged from a Bf 109B, but in the case of the AS-6, it was fixed. Initially, a landing skid was used on the rear, which was later replaced with a landing wheel instead.
The canopy and landing gear was taken from a damaged Bf 109 aircraft [ufxufo.org]
Testing the Prototype
Initial evaluation tests of the AS-6 prototype were conducted at the Luftwaffe Brandis Airbase. The flight tests were conducted by Rolf Baltabol Junkers test pilot. While several short take-offs were made, there were no attempts to actually take the aircraft to the sky. The test pilot noted that the aircraft had an overall poor design and was difficult to control. He urged that the control surfaces and rudder be completely redesigned. The engine was also deemed too weak. During the last short take-off, one of the two landing gear assemblies was damaged.
The AS-6, following its unsuccessful start, spent several weeks in repairs and received a number of modifications in an attempt to improve its performance. These included adding an additional 70 kg of weight to the rear, installation of brakes taken from a Ju 88, and repositioning the landing wheels to the rear by about 20 cm. Sack proposed moving the landing wheels further back, but the test pilot Rolf simply refused to fly it if this change was implemented. He argued that placing the landing gear to the rear would imbalance the aircraft potentially leading to tipping forward during a take-off. For this reason, the modification was not implemented. While the engine was underpowered, there were simply no alternatives available at that time.
The AS-6 during testing [falkeeins.blogspot.com]The next test was scheduled for April 1944. During these tests, Rolf tried to take it to the sky, but failed again to do so. This time it was noted that the wings were simply too short. Further tests were canceled, the AS-6 was to await more modifications, and was to be tested in a wind tunnel; if possible with a completely new engine.
The fate of the AS-6
Following the unsuccessful testing, the AS-6 was stored at the Brandis airfield. In the summer of 1944, this airfield became the main operational base for the experimental Me 163 rocket-powered aircraft. The pilots of the I./JG 400 (charged with testing the Me 163) found the AS-6. One of its pilots, Franz Rossle, expressed a desire to attempt flying the unusual plane. But when the ground crew was preparing the aircraft for take-off, one of its landing gear units simply broke due to rough terrain, effectively preventing the test flight to be conducted. After this, it was once again stored at Brandis. It would remain there until early 1945 when it was lost in an Allied bombing raid.
The AS-7 project
While not clear when (possibly during early 1945), Sack approached Messerschmitt company with a proposal to use his circular-wing design on the Bf 109K-4 aircraft. The aircraft marked as SA-7 would be powered by a DB 605 2,000 hp engine. Fitted with circular wings it was theorized that it would be capable of carrying more armament inside the wings. It is believed (but not clear) that Messerschmitt was interested in this proposal and designated the project Me 600. Due to the war’s end, nothing really came from this project.
Conclusion
While certainly an unusual and interesting design, due to poor quality and salvaged materials used during its construction, the AS-6 performed poorly and never actually achieved flight. We will never know if the AS-6 circular-wing design offered any major advantage over more conventional wing designs. It appears that Arthur Sack did not continue with his idea after the war and passed away in the mid-1960’s. While his work was never implemented in mass production, his unusual design was often mistakenly taken as some advanced and secret German World War II project, which ironically, it never was.
He 112 the unsuccessful competitor of the Bf 109. [luftwaffephotos.com]Prior to the Second World War, the German Luftwaffe was in need of a new and modern fighter that was to replace the older biplane fighters that were in service. While four companies responded to this request, only the designs from Heinkel and Messerschmitt were deemed sufficient. The Heinkel He 112 was an especially good design that offered generally acceptable flight characteristics and possessed a good basis for further improvements. While it was in some regards superior to the Messerschmitt, ultimately it would not be accepted for service, and only 100 or so aircraft would be built. These would be mainly sold abroad, with those remaining in Germany used for various testing and evaluation purposes.
History
By the early 1930s the Heinkel company was a well-established aircraft manufacturer. It was rapidly expanding, mostly thanks to the export of some of its aircraft designs. The Heinkel company also had a good relationship with the German Air Ministry RLM (Reichsluftfahrtministerium RLM), which entered a series of different aircraft production contracts with Heinkel.
At this time the German Air Force was in the process of a huge reorganization, and the development of new military aircraft. Quite of interest was the development of a new fighter aircraft that would replace older Arado Ar 68 and Heinkel He 51 biplanes that were in service. For this reason, in May 1934 the RLM issued a competition for a new and modern fighter plane that could reach speeds of 400 km/h (250 mph) at an altitude of 4,000 meters (19,685 feet). Initially, three companies were contacted, including Arado, Focke-Wulf, and Heinkel. Interestingly, and somewhat ironically as it later turned out, Messerschmitt, a relatively small company at that time, was also contacted by the RLM.. All four companies were to build three prototypes of their design, which were to be tested before a final decision was to be made.
Arado and Focke-Wulf completed their prototypes, the Ar 80 and Fw 159 respectively, by the end of 1934. The Heinkel He 112 and Messerschmitt Bf 109 prototypes took a bit longer to complete, which was completed in September 1935. The He 112’s design was greatly inspired by the He 70 passenger plane, which would later be modified for military purposes. Heinkel engineers used the He 70’s the overall design as the basis for the He 112, mainly regarding its wings and the fuselage construction.
The inspiration for the He 112 was the He 70. While the He 70 had good general performance it would not be employed by the German in any major military role. [Wik]Once all four companies submitted their designs, evaluation trials were carried out at the German test centers located at Rechlin and Travemunde starting in October of 1935. After some initial testing, both the Ar 80 and Fw 159 experienced too many mechanical breakdowns and even crashes, which ultimately led to both being rejected. The He 112 and Bf 109 on the other hand proved to be more promising designs. Interestingly due to shortages of domestically built engines, both aircraft were initially powered by Rolls-Royce Kestrel engines.
The He 112 V1 (D-IADO) was powered by a 695 hp Rolls-Royce Kestrel Mk. II engine during trials. Once the aircraft was completed, it was first flight-tested by Heinkel’s own test pilot Gerhard Nitschke. While he gave a generally positive review of its performance, he also noted the aircraft’s drag was a bit higher than expected. However, given that its overall performance was deemed sufficient for the competition, Heinkel decided to proceed with the project. This prototype arrived at the designated test center of Travemunde by the end of 1935. During a series of flight tests, the maximum speed achieved was 466 km/h (290 mph).
The He 112 V1 first prototype, used for the trials held at Rechlin and Travemunde. [luftwaffephotos.com]It was clear that the RLM would never accept an aircraft powered by a foreign engine. The Heinkel engineers began working on the second prototype that was to be equipped with a domestically built engine. The V2 (D-IHGE) was powered by a 640 hp Junkers Jumo 210C liquid cooled engine. The first test flight was made in November 1935 by another Heinkel test pilot Kurt Heinrich. The V2 was more or less just a copy of the first prototype.
Construction of Additional Prototypes
During the series of test flights, the performance of the two competitors was quite similar, with some minor advantages between them. In the case of the Bf 109, it was slightly faster, while the He 112 had lower wing loading. In addition, the He 112 had a better design and safer landing gear unit.
As the V2 was flight tested at Heinkel, the initial results of the competition began to arrive. The Heinkel engineers were keen on finding a way to overcome the Bf 109’s slightly faster speed. So the Gunter brothers began to redesign the V2 wings. Walter and Siegfried were at that time, probably Heinkel aircraft designers (for example the He 51 biplane is one of their designs.). Their calculation showed that a reduction in the wing profile would provide an additional boost to the maximum speed by at least 24 to 29 km/h (15 to 18 mph). This modification reduced the overall size of the wings, but led to another problem. Namely, the wing loading exceeded that of the RLM commission requirement. Given that the aircraft speed was increased, Heinkel officials deemed that it was a necessary compromise that would not affect the general rating of the aircraft.
The V2 prototype reached the Travemunde test center sometime in early 1936. In February 1936 the V1 and V2 prototypes were moved to the Rechlin Testing Center. In early March, a series of dive tests were carried out. In one of these, the V2 was seriously damaged, luckily the pilot survived the crash. After a few weeks of repairs with Heinkel, the aircraft was quickly put back to use. But in another landing crash, it was completely destroyed and listed as irreparable. Once again the test pilot managed to escape without any injury. This accident, while it did not prevent Heinkel’s involvement in the new fighter competition, it certainly affected the commission’s opinion on the He 112 at least to some extent.
The last of the prototypes intended for the competition was the V3 (D-IDMO). While initially, it was more similar to the first prototype, it received the wing modification implemented on the V2. Additional changes include increasing the rear tail unit size, adding a new radiator, installation of three (or two depending on the source) 7.92 mm MG 17 machine guns. In addition, it would later receive a new enclosed cockpit with a sliding canopy.
Side view of the V3 (D-IDMO) prototype. [luftwaffephotos.com]
Further Competition Developments
Despite the series of improvements to their He 112 design, the tide was slowly but surely turning toward the Bf 109. The RLM commission was getting somewhat frustrated with Heinkel’s constant changes to the design, and the previously mentioned crash did not help matters. In March, it was already being discussed to proclaim the Bf 109 as a winner. The Germans were also informed by the Abwehr intelligence service that the British were developing and preparing for the production of the new Spitfire. RLM officials were simply not willing to risk taking a chance on an aircraft design that could not quickly be put into production, as the Bf 109 was.
While the He 112 project would have ended there, thanks to Heinkel’s strong political connections, an extension of the trials was agreed to. Both companies were to build additional 15 0-series aircraft to be used for testing. The production was to commence in October 1936 with the last aircraft to be completed by May the following year.
Heinkel’s first completed aircraft, which was included in the previously mentioned contract, was actually a He 112 V4 (D-IDMY) prototype which was ready in June 1936. The V4 received a new and stronger 680 hp Jumo 210D that was equipped with a supercharger. In addition, it had an open cockpit, besides which it was in essence a copy of the V3. Possibly anticipating the contract for additional aircraft, Heinkel began working on additional airframes in advance. This led to the completion of the V5 (D-IIZO) and V6 (D-IQZE) prototypes in July of 1936. The V6 was intended as a replacement for the lost V2 aircraft. This aircraft was powered by a Jumo 210C engine. The last aircraft of the prototype series was the V8 (D-IRXO) powered by a Daimler DB 600A engine. It was primarily intended to serve as test aircraft. All of these previously mentioned prototypes were to serve as the forerunners of the He 112 A-0 series.
The V4 prototype before it received any markings. [luftwaffephotos.com]Following more test flights by numerous Luftwaffe pilots, the Bf 109 was receiving more and more positive reviews from pilots that had the opportunity to fly them. The Bf 109, while proving to have excellent flying performance, was also cheaper and easier to build than the He 112. Given the fact that the Germans were attempting to accelerate the production of the new fighter, this was seen as a huge advantage over the He 112.
In late 1937 Ernst Udet, who was at that time the director of the RLM technical development sector, visited the Heinkel company Marienehe Test Site. There he informed Heinkel that his He 112 was rejected as a fighter. Possibly to compensate for the huge investment in the fighter project, Heinkel company was permitted to export the He 112.
Heavy Fighter Role
Parallel with the development of the first fighter aircraft, the RLM was also interested in the so-called Zerstorer (heavy fighter). This aircraft was to be armed with cannons and machine guns. Heinkel proposed that the V6 be armed with a 2 cm MG C/30L cannon placed in the centerline of the engine. According to D. Bernard the V6 was designated for further testing, under real combat conditions, and would be sent to Spain at the end of 1936. It would be lost there in a landing accident in July 1937. Ernst Heinkel was likely dissatisfied with this outcome, as Messerschmitt once again triumphed as its Bf 110 would be accepted for this role.
The A and B series
Despite being inferior to the Bf 109, the Heinkel company continued working on the He 112, improving its design, in the hopes of gaining the attention of the RLM. The construction of the limited production He 112 A-0 series was still underway, with a total of only six aircraft (D-ISJY, D-IXHU, D-IZMY, and D-IXEU) built. The last two aircraft of the A-0 series received no registration numbers, as they were intended to be sold to Japan. The remaining four aircraft were used for various proposals. For example, the A-01 aircraft was to be used as a base for the proposed He 112 C-0 aircraft carrier modification, which was never implemented. The A-02 and A-04 were used for further flight tests. The A-03 was mainly used as an exhibit aircraft for various European aviation exhibitions, which were quite common before the war.
The A-series was built in small numbers and mostly employed for testing various equipment and design changes. [luftwaffephotos.com]The A-series was built in small numbers, as Heinkel’s attention moved to the B-0 series instead. The B-0 series was quite different from the previous version, as it introduced a number of changes and modifications. Some of which included a new cockpit design, more powerful armament, changes to the engine ventilation design, fuselage and engine cowling changes, and other modifications.. The forerunner of the B series was the He 112 V7 prototype, which included many modifications previously mentioned.
Following the unsuccessful attempt to gain the Luftwaffe’s attention Heinkel and his team of engineers began working on redesigning the He 112. The basis for the next version, the He 112B-0, the V7 (D-IKIK) was reused. It incorporated a newly redesigned wings and tail unit, and was to be powered by a 1,000 hp Daimler DB 600A engine. Heinkel officials and Hertel himself were hoping that this new version could potentially persuade RLM to reconsider the He 112. Following it was the V9 (D-IGSI), which was powered by a weaker 680 hp Jumo 210E engine. In the following months, work on the B-series was intensified with many different engines being tested (Jumo 210E, 210G etc). Ultimately meager export sales, and the RLM’s rejection of the He 112 by the start of 1939 forced Heinkel to finally terminate the project.
The B-series was in many aspects a complete redesign from the previous series. Including the introduction of a new tail unit, and part of the fuselage, to name a few [luftwaffephotos.com]
Rocket Engine Tests
Prior to the Second World War, the Germans were quite interested in the experimentation and the development of rocket technology. Various tests conducted by Dr. Wernher von Braun were carried out at the Kummersdorf-West test centers. While this research eventually led to the creation of the infamous V-2 rocket, the development of rocket engines that were intended to possibly be installed in aircraft is often overlooked. Ernst Heinkel was quite a supporter of this project and even donated a number of aircraft to be used as testbeds for the potential new engine. He even donated a few pre-production series He 112 for this research.
A rocket engine was installed in the rear of the fuselage, with the engine nozzle being placed just beneath the tail unit. During the first ground test, the engine exploded, destroying the aircraft (He 112 A-01) in the process. Another He 112 V3 aircraft was outfitted with the rocket engine and was being prepared to conduct its first test flight. As the pilot was approaching this aircraft, the rocket engine exploded again. Somewhat miraculously the pilot survived with no major injuries. While again the aircraft was lost, another aircraft that was built as a replacement would receive the same markings.
The V3 prior to the start of testing. Which would spectacularly explode shortly after the picture was taken. [luft46.com]Von Braun requested another aircraft which Henkel provided, this was the He 112 V8. During these trials it received a slightly altered designation V8/U. The plane was to ascend on its own piston engine. Then at a certain height, it was to fire the rocket engine wich was placed to the rear of the fuselage for a 30-second burst. This flight test was carried out in April 1937 and was more than successful. During the short burst, the plane reached a speed of 460 km/h (286 mph). The He 112 V8 was returned to Heinkel but two more aircraft (H7/U and A-03) would be donated for the rocket research program. The V8 would be eventually sent to Spain in 1937 and its final fate is unknown. Thanks to the He 112, the German rocket engine program gained a huge boost, which would eventually lead to the He 176 and later Me 163.
Technical Characteristics
The He 112 was an all-metal single-engine fighter. The monocoque fuselage consisted of a metal base covered by riveted stress metal sheets. The wing was slightly gulled, with the wingtips bending upward, had the same construction as the fuselage with a combination of the metal construction covered in stressed metal sheets.
During its development life, a great number of different types of engines were tested on the He 112. For the main production version, He 112 B-2, the 700 hp Jumo 210G liquid-cooled engine was used. With this engine the maximum speed achieved was 510 km/h (317 mph). For the Jumo engine, an all-metal three blade variable pitch propeller was used. The He 112 had a fuel capacity of 101 liters in two wing mounted tanks, with a third 115 liter tank placed under the pilot seat
The landing gear were more or less standard in design. They consisted of two larger landing wheels that retracted into the wings, and one smaller wheel placed at the rear. The He 112 landing gear was wide enough to provide good ground handling and stability during take-off or landing.
The pilot cockpit received a number of modifications. Initially, it was open with a simple windshield placed in front of the pilot. Later models had a sliding canopy that was either partially or fully glazed.
While the armament was changed during the He 112’s production, the last series was equipped with two 7.92 mm MG 17 machine guns and two 2 cm Oerlikon MG FF cannons. The ammunition load for each machine gun was 500, with 60 rounds each for the cannons. If needed, two bomb racks could be placed under the wings, with one per side. Each could carry one 10 kg anti-personnel bomb. For the acquisition of targets, the pilot used the Revi 3b gun sight.
Brief Service with the Luftwaffe
Despite losing to the Bf 109, Heinkel was permitted, after some lobbying from Ernst Heinkel himself, to send one He 112 to Spain for combat evaluation. Once it reached Spain during the end of 1936, the He 112 was allocated to the Experimental Fighter Unit 88 which was part of the Condor Legion. In Spain, it was mostly used against ground targets. One of its greatest successes happened during an attack on the Republican-held Cesena train station. The pilot, Obereutnant Balthasar, made three attack runs in which he managed to destroy an armored car and a tank. The aircraft would be lost in a landing accident that happened in July 1937. Two more prototypes would be sent to Spain during 1938, the V8 and V9. The V8 was heavily damaged during initial trials and spent some four months in repairs. The V9 had a better service life, as it was used in a number of ground attacks. Both aircraft would be returned to Germany by the end of 1938.
Only a small number of He 112 (less than 20) saw limited service with the Luftwaffe in 1938 [luftwaffephotos.com]In 1938 a possible conflict with Czechoslovakia and the Western Allies, France, and the United Kingdom over the dispute caused huge concern in the RLM. The Luftwaffe was simply not ready for open war, as it was not yet fully equipped. For this Reason, the RLM instructed that all available aircraft be relocated to the Luftwaffe to temporarily boost their readiness numbers. An unknown number of He 112 B, taken from the Japanese purchase order, were temporarily pressed into service. These were allocated to the IV./JG 132 station at Oschatz. In November they relocated to Mahrish-Trubau. Once the crisis was over, the aircraft were replaced with the Bf 109. The pilots that had the chance to fly them gave a generally positive review of their flying performance.
Export Attempts
As mentioned earlier, the He 112 was permitted to be exported abroad if there were any interested customers. This order was officially given at the end of January 1938. A number of countries such as Austria, Japan, Romania, and Finland showed interest, but only a few actually managed to procure aircraft.
Negotiation with Austria
During November 1937 an Austrian delegation visited Heinkel with a desire to enter into a purchase agreement for acquiring 42 He 112B aircraft. Due to lack of funds, this order was reduced to 36 at the start of 1938. Eventually, nothing came of this as the Germans simply took over Austria in March 1938.
In Japanese Hands
At the end of 1937, a Japanese delegation made a contract with Heinkel for purchasing 30 He 112B’s. If these proved to be satisfactory, an additional order for 100 would be placed. This order included 2 He 112 A-0, 6 B-0, and 21 B-1 and the V11 prototype. After a series of tests, the Japanese were not impressed with the He 112 and did not accept it for service. The experimental He 112 C aircraft carrier version was also sold to Japan, according to D. Bernard.
J. R. Smith and A. L. Kay provide a completely different story. According to them, Japan expressed an interest in buying 30 He 112B-0 aircraft, with the first group of 12 aircraft arriving in Japan in 1938. While the remaining 18 were to arrive soon after, the Sudeten crisis changed the plan. The Germans were preparing for a potential war with Czechoslovakia and needed every possible aircraft. So they requisitioned the aircraft intended for Japan. Once the crisis was over, Heinkel offered to ship these delayed aircraft to Japan, which rejected the offer. The Japanese were disappointed with the He 112 B-0 performance and decided to cancel the purchase. The sources also conflicted with each other if the He 112 in Japanese service ever saw action.
In Spain
Some three He 112 were tested during the Spanish civil war. Thanks to this, Francisco Franco’s forces had some insight into the He 112’s performance. Based on this, Spain initially asked for 12 aircraft. The order would be eventually increased to 18 aircraft. Interestingly, Spanish pilots managed to shoot down an Allied P-38 that likely accidentally entered the Spanish air space while flying the He-112B-0 in 1943.
He 112 in Spain’s service. [luftwaffephotos.com]
In Romania
Romania initially asked for 24 aircraft, with the order later increased to 30 He 112 aircraft. These arrived from June to October (or September) 1939. The Romanian He 112 would be used during 1941 against the Soviet Union. The following year, all would be allocated for pilot training.
Romanian He 112 even saw service against the Soviet Forces during 1941. [luftwaffephotos.com]
Hungary
The last nation that operated the He 112 was Hungary. In September 1937 a delegation from Hungary visited Heinkel where they inspected the He 112. This delegation was satisfied with what they saw and ordered 36 aircraft, but also showed interest in a licensed production. Ultimately the RLM rejected this offer and only one aircraft ever reached Hungary.
Other Unsuccessful Negotiations
Prior to the war, Heinkel organized a series of demonstrations of the He 112B to various interested European air forces. These include Yugoslavia, The Netherlands, Finland, Turkey, and Switzerland. While many of these parties were interested, for various reasons, chiefly budget constraints, nothing came of these negotiations.
Production
The production numbers of the He 112 are not clear and vary widely depending on the source. According to F.A.Vajda and P. Dancey the production run was as follows with 3 in 1935, 11 in 1936, 13 in 1937, 30 in 1938, and 46 in 1939 for a total of 103 aircraft. Author D. Berliner mentioned a number of 66 aircraft being built. Author Duško N. gave a number of 68 aircraft of all versions being built. D. Bernard gave us a number of 98 aircraft. While C. Chants mentioned a number of 110 aircraft.
Prototype and Production Versions
He 112 V1-V – Prototype series used for testing of various engines and overall design
He 112 A – Planed main production version, which was not adopted
He 112 B – Extensively modified versions of preceding models
He 112 B-1 – Equipped with a Jumo 210E engine
He 112 B-2 – Equipped with a Jumo 210G engine
He 112 B-3 – Proposed version powered by a Daimler DB 601A engine, none built
He 112 C – A proposed aircraft carrier version, only one prototype was built and sold to Japan
He 112 E – Intended as an export version, based on the B series
He 112 U – Propaganda aircraft, which was actually based on the He 100
Operators
Germany – Briefly operated a small number of the He 112
Japan – Operated some 12 to 30 aircraft mainly for testing
Spain – Operated less than 20 He 112 aircraft
Romania – Purchased some 24 to 30 He 112, which saw combat action against the Soviet Union
Hungary – Purchased one He 112
Austria – Planned to acquire 42 He 112, but nothing came from this as it was annexed by Germany.
Conclusion
The He 112 during its brief service life was shown to be a good fighter aircraft. It proved to be a worthy competitor to the Bf 109. It’s quite difficult to pinpoint the exact circumstances that ultimately led to its downfall. Sources often mention that one of the main reasons was political involvement, which favored Messerschmitt. Political quarrels in Germany often influenced decision to adopt aircraft during the war. This factor was surely at play when the fate of the He 112 was decided. But a more practical answer was simply that the Bf 109, while shown to have good flying performance, was also cheaper and easier to build than the He 112. Given that at that time, the Luftwaffe was in the middle of a huge reorganization and rearmament effort, conditions certainly favored the Bf 109. The He 112’s constant design changes did not help either.
He 112B-2 Specifications
Wingspans
29 ft 10 in / 9.1 m
Length
30 ft 2 in / 9.22 m
Height
12 ft 7 in / 3.82 m
Wing Area
180 ft² / 17 m²
Engine
One 700 hp Jumo 210G liquid-cooled engine
Empty Weight
3,570 lbs / 1,620 kg
Maximum Takeoff Weight
4,960 lbs / 2,250 kg
Climb Rate to 6 km
In 10 minutes
Maximum Speed
317 mph / 510 km/h
Cruising speed
300 mph / 484 km/h
Range
715 miles / 1,150 km
Maximum Service Ceiling
31,170 ft / 9,500 m
Crew
1 pilot
Armament
Two 20 mm cannons and two machine guns 7.92 mm machine guns
Illustrations by Godzilla
He 112 as seen during its brief service with the LuftwaffeAn alternate livery of the Luftwaffe He 112He 112 in Romanian ServiceHe 112 in Romanian ServiceHe 112 v5 as it was tested by Japan
Credits
Written by Marko P.
Edited by by Ed Jackson & Henry H.
Illustrations by Godzilla
Sources
Duško N. (2008) Naoružanje Drugog Svetsko Rata-Nemаčaka. Beograd.
D. Monday (2006) The Hamlyn Concise Guide To Axis Aircraft OF World War II, Bounty Books.
D. Berliner (2011) Surviving fighter aircraft of World War two, Pen and sword
F.A.Vajda and P. Dancey (1998) German aircraft industry and production 1933-1945, Airlife Publishing Ltd.
J. R. Smith and A. L. Kay (1990) German Aircraft of the Second World War, Putnam
D. Bernard (1996) Heinkel He 112 in Action, Signal Publication
R.S. Hirsch, U, Feist and H. J. Nowarra (1967) Heinkel 100, 112, Aero Publisher
C. Chants (2007) Aircraft of World War II, Grange Books.
German Empire (1915)
Reconnaissance Aircraft – 267 Built
A Roland C.II in flight. [Roland Aircraft of WWI]The Roland C.II was a reconnaissance aircraft built by LFG Roland in 1915 as a new and innovative design. The type would see widespread use by the German Empire and, thanks to its highly advanced form, became the fastest and most maneuverable of its type when it was introduced. Overall improvements on the aircraft were done throughout the war to strengthen its performance, but by the end of the war, much more advanced aircraft had been deployed and made the Roland obsolete. The C.II was relegated to a training aircraft until the end of the war, when all were scrapped.
Development
In early 1915, the Luftfahrzeug Gesellschaft (L.F.G.), also known as Roland to avoid confusion with a similar sounding design firm, began building several Albatros aircraft under license. These aircraft were the Albatros B.I, B.II and the C.I, which were considered some of the most advanced in terms of aerodynamics for the current times. Around the same time, Dipl.-Ing. (Engineer) Tantzen would join Roland as chief designer. With Tantzen as the chief designer and their experience gained from license-building aircraft, Roland would begin designing a new and original plane, the C.II.
Work began on the C.II (C-types were two-seat armed aircraft) sometime in mid 1915. The C.II would have a very rounded, aerodynamic fuselage design, similar to the Albatros D.III fighters of the following year. The fuselage was created in a unique way, called Wickelrumpf (Wrapped body). Wickelrumpf involved using layers of veneer strips that were wrapped around a simple wodden frame. The shells created were then glued together around the wooden frame of the C.II and strengthened with fabric, making a very streamlined and sturdy fuselage. This whole process was an early attempt at monocoque construction, which involved having a shell built around a frame. However, the Wickelrumpf technique on the C.II used two stringers for the frame, a feature true monocoque aircraft don’t have. Like the fuselage, the wings were also designed to be very aerodynamic. Instead of having the wings connected with multiple spars and bracings, as was common with aircraft of the time, the wings of the C.II would be connected via a single wooden strut in a single bay wing.
The C.II prototype on October 24th, 1915, only hours before its disastrous test flight.
Before a prototype was completed, a C.II fuselage was mounted on a railcar for aerodynamic testing and other experiments. The train would swiftly go down a straight track between the cities of Schoneberg and Juterbog and data would be recorded on the aircraft. The first prototype C.II was completed in October of 1916 and its first test flight would happen between the 24th and 25th. This test flight would end in misfortune, with the D.III engine failing mid flight, resulting in a crash and subsequent damage to the aircraft. The prototype was quickly repaired and flying, with a second prototype completed soon after. In the test flights, it was found that, thanks to its aerodynamic design and powerful D.III engine, the C.II’s speed was extraordinary, surpassing all of the current C-type aircraft then in use. With such a feat, a production batch of 50 aircraft were ordered on December 23rd, 1915. Testing continued and it was found that the wing cells were slightly unstable, so an additional drag wire was added for stabilization. After this change was added to the design and prototypes, production of the type continued and, by March 7th, 1916, the first of the production aircraft were ready to be sent to the front.
Design
The last production batch of C.IIs [Roland Aircraft of WWI]The interior frame of the C.II. This would be covered by the Wickelrumpf shells. [Roland Aircraft of WWI]The Roland C.II was a two seat observation biplane. The body of the C.II was aerodynamic in shape and had a plywood frame, with the outer shell created via Wickelrumpf and made of veneer strips glued together and supported with fabric. Wickelrumpf produced a semi-monocoque fuselage. The body would have two seats, one for the pilot and one for an observer. On the sides of the fuselage were two pairs of celluloid windows for the observer to use. On several occasions, flight crews would paint curtains onto them. The windows themselves were modified by the crews to open by sliding backwards or downwards, but this was not a standard feature. Above the pilot’s position was a roll cage designed to prevent the pilot from being crushed in the event of a roll over on the ground. The initial design of the cage was circular but, once the frontal Spandau was added, the cage had to be redesigned and became more triangular in shape. No measure was given to protect the observer. The C.II used a Mercedes D.III engine mounted in the nose and driving a wooden propeller. The first two cylinders were exposed to the elements. The area surrounding the engine was the only part of the aircraft to have metal plating. Certain plates were hinged to allow for maintenance to the engine. For exhaust, the initial models used the “ocarina” style pipes, but later models would change between the ocarina style and others. The engines would have two ear radiators on each side of the craft. These protruding radiators obstructed airflow and caused drag. The tailfins were wooden and fabric covered. The control surfaces were made of steel tubes and covered in fabric. The tailfin was enlarged after the June 1916 batch to increase stability.
A sight all too common of the C.II. Due to its poor downwards visibility, Pilots had trouble landing the aircraft. [Roland Aircraft of WWI]The wings of the aircraft were made of wood and covered in doped fabric as was conventional at the time, with the control surfaces being made of steel tubes and also covered in doped fabric. The ailerons were originally in the lower wing but, starting with the C.IIa, these would be located in the upper wing. The wings themselves were the exact same length, shape and chord. Unique I-struts connected the wings together. The I-struts were of plywood construction and would have interior bracings in the shape of an X. The C.II would have a landing gear connected to the aircraft with v-shaped connectors. At the rear of the aircraft would be a landing skid.
Mid Production C.II [Roland Aircraft of WWI]For armament, the C.II initially only had a single Parabellum 7.92 mm for the observer to use. After the first 50 aircraft, a forward firing synchronized Spandau 7.92 mm was added for the pilot. If needed, four bomb racks could be fixed to the underside of the wings to carry small bombs. The aircraft also carried several flares. A radio could also be carried on the aircraft and used by the observer. This was powered by an airscrew-powered dynamo located near the landing gear.
The “Walfisch” In Action
Otto Czernak’s C.II. This aircraft was modified with a rudimentary machinegun mount and an input system for the observer to request certain flight movements. [Roland Aircraft of WWI]The Roland C.II arrived on the frontline in late March of 1916 and the effort put into its aerodynamic design was noted almost immediately. The C.IIs were the fastest aircraft used by the Luftstreitkräfte (German Air Force) at their introduction, outpacing all of their operational aircraft and almost all opposing Allied aircraft, only being superseded by a handful of Allied fighters. Because of its impressive speed, the Roland C.II was flown in special groups, as other two seater C-type aircraft could not keep up with the type. The Roland C.II was initially used as a reconnaissance plane, with the second crewman acting as the observer, but its speed allowed it to be used on escort duties as well. Despite its good speed, however, the C.II was not without its flaws. In the observer role, thanks to the crewmen being seated above the body, visibility above the plane was superb, but visibility in front of the aircraft was lacking, and visibility beneath the aircraft was poor. An attempt to fix this early on, before production began, was placing cutouts in the base of the wings, but this solution still do not provide adequate visibility. This flaw became fatal later on, once enemy pilots learned of this massive weak spot, as they would now dive beneath a C.II, then fly upwards towards it, firing their guns while the Roland crew had no means of detecting threats from that angle. This visibility issue also made landings especially dangerous, as the pilot had difficulty calculating how close the ground was. Aircraft of the time were well known to have difficulty upon landing, but the Roland C.II exhibited worse than average landing performance due to the visibility issue. Maneuverability and stability of the C.II was also lackluster at times and would need improvement.
Initially, the Roland C.II only had a single Parabellum 7.92 mm machine gun for the observer to use. The first fifty of these aircraft would have this small armament. Many of the pilots found this weak armament lacking. One pilot in particular, Lt. Otto Czernak of Schusta 28, would fix this issue on his own. He would rig up a forward firing apparatus for another Parabellum machine-gun that would allow the pilot to fire. Due to the propeller and machine-gun not being synchronized, the rig placed the gun well above the rotating radius of the propeller, making the rig very tall. Czernak’s own plane was modified in other ways as well, having a unique input system for his observer that would allow the 2nd crewman to communicate to Czernak to maneuvering instructions. No other C.II would have this system. After the first fifty aircraft, all C.II’s would have a synchronized Spandau machine-gun for the pilot to use. This gave the C.II some dogfighting ability, which is how it would end up being used for escort duties, along with its excellent speed.
A Linke-Hoffman produced C.IIa(Li). This particular aircraft has bomb racks installed. [Roland Aircraft of WWI]At some point, either during its career or while it was still being developed, the C.II was given the unofficial nickname of Walfisch (Whale). The origin of this name has been told many times but there is no concise point that has been confirmed. The most common of these origins is said to have come while it was still in development, from a German official observing the type. Another reason could have been its overall round shape and how the early models were painted a silver-white color. Nonetheless, the name stuck around. The name Walfisch did not seem to have any negative connotation for its pilots, as many of them would paint fish or shark faces on their aircraft. Some would even paint scales. The previously mentioned Otto Czernak would paint a fish face onto his aircraft. This tradition was seen throughout its lifespan, even after the later two-toned camouflage models were introduced with green and brown paint.
A production of 24 aircraft, after the initial batch, with the modified machine-gun was ordered in March of 1916. Another batch of 45 aircraft was ordered in April. However, the batch of Roland C.IIs after this set would aim to fix many of the stability issues found with the aircraft in the field. The tailfin was enlarged to improve flight performance. The wings were shortened and the I struts were moved inward to compensate for the wing flexing. These made the wings much more structurally sound. This reworked design of the C.II was known as the C.IIa and testing of the type began in April and May of 1916. The type would be sent to the frontline by the summer. All C.II aircraft after this point would be of the C.IIa model. A batch of 19 C.IIa was ordered in April of 1916 and another batch of 36 C.IIa was also ordered, but with the ailerons in the upper wing. All aircraft after this would have the ailerons this configuration. A batch of 40 C.IIas was ordered in June of 1916 and would have a larger vertical fin to improve stability.
Production C.II [Roland Aircraft of WWI]Most of the production Roland C.IIs were flying by the mid summer of 1916. The C.II was used extensively at the Battle of the Somme, where it was used in large numbers for recon and escort duties. On the second day of the Battle of the Somme, June 2nd, the soon-to-be-famous Albert Ball would go on a sortie in a Nieuport scout aircraft. While flying, his squadron would encounter 6 Roland C.IIs on patrol. The Allied squadron would begin their attack, while the Roland formation scattered. Ball was able to catch up to one and shoot it down, causing the C.II to plummet near the Mercatel-Arras road. This would be the first aircraft Ball completely destroyed in flight (There were several confirmed victories before this, but this was the first confirmed complete destruction of an aircraft). Many of Ball’s early kills were Roland C.IIs. Ball himself went on to compliment the C.II, stating it was the best aircraft the German’s had at the time, with a good defense to compliment its speed.
A C.IIa in two tone colors. This particular aircraft has been decorated by its crew, including painted on curtains over the celluloid covers and a shark mouth. [Roland Aircraft of WWI]The Roland C.II was continually used through the rest of 1916. By summer, the Linke-Hofman company would begin license building C.IIs. An initial batch of 16 aircraft was ordered. The aircraft built under license were known as C.IIa(Li). In July of 1916, a batch of 40 aircraft was ordered to be produced by Linke-Hofman. This would be the last batch of C.IIs built and would be sent to the front in the beginning of 1917. By this time, however, the C.II had lost its performance edge. The Allies had fielded newer and improved aircraft that were able to easily keep up with the C.II, and the Germans had also produced newer aircraft that performed better. The C.II was instead returned from the front lines and used as a trainer for the C-type in flight schools. The C.II would perform this duty until hostilities ended in 1918. The fate of the remaining C.IIs is unknown, but they were most likely scrapped. No aircraft survive to this day.
The Roland C.III: A Derivative Design
The Roland C.III. It is apparent its design is based off of the C.II. Very little is known about this aircraft. [Roland Aircraft of WWI]In mid-1916, a derivative design of the C.II emerged; the Roland C.III. The C.III shared many of the same design features of the C.II, such as a two-seat aerodynamic body with two windows on each side for observation purposes. However, most of the similarities stop there. The C.III was designed to use the more powerful 200 hp (149 kW) Mercedes D.IV engine over the C.II’s D.III. Based on the few pictures available, the prototype C.III appears to still use a D.III engine, most likely to test the airframe before the larger engine was placed. To compensate for a stronger engine, the wings of the C.II were made larger. The wings themselves were also reworked. Instead of having single bay wings with flat strut connectors, like the C.II, the C.III instead had the standard two bay wings typical of aircraft of the era. This was most likely done as the single struts of the C.II happened to obscure the vision of the frontal windows. The tail design of the C.III also differed from the C.II. Very little is known of the C.III outside of these few details, including whether or not it even flew or any further testing. The single C.III prototype was lost when LFG’s facility in Adlershof was destroyed in a fire on September 6th, 1916. This incident is cited to be caused by sabotage from British Special Forces. After the loss of the prototype, no further work on this type was done.
Conclusion
A lineup of several early C.IIs [Roland Aircraft of WWI]At the time of its introduction, the C.II was one of the most advanced aircraft Germany had. Its powerful engine and aerodynamic construction allowed it to outperform most of its opposition. As the war continued, more advanced machines eventually outpaced the Roland C.II. The aircraft did manage to influence other companies to attempt more aerodynamic designs. Roland would continue building planes, including newer C-types (C.V and C.VIII) and fighter types, both of which would use Wickelrumpf. Two other aircraft were built off of the C.II’s design, the D.I fighter and the WD floatplane. Despite continuing to make newer aircraft, none of Roland’s designs would ever garner the same fame as their “Walfisch”, and it would remain their most iconic design of the war.
Variants
LFG Roland C.II Prototype – The prototype model of the C.II differed from the production version in several ways. Notably, it only had one set of windows. Two of these were built.
LFG Roland C.II – Standard model for the Roland C.II. After the initial batch, all aircraft would use a synchronized machine-gun in the nose.
Otto Czernak’s LFG Roland C.II – A modified early production C.II used by Otto Czernak of Schusta 28. It had a makeshift machine-gun mount and a unique input system for the observer to request movements from the pilot.
LFG Roland C.IIa – Later modified model of the C.II, had improved wings and a larger tailfin.
LFG Roland C.IIa(Li) – Designation given to C.IIa planes license-built by Linke-Hofman.
LFG Roland C.III – Derivative aircraft based on the C.II. Heavily reworked the wings and was given a Benz B.IV engine.
Operators
German Empire – The Roland C.II served as a reconnaissance aircraft and an escort aircraft in several squadrons of the Luftstreitkräfte from 1916 to 1918
LFG Roland C.II Specifications
Wingspan
33 ft 10 in / 10.33 m
Length
25 ft 3 in / 7.7 m
Height
9 ft 6 in / 2.9 m
Mean Aerodynamic Chord
4 ft 11 in / 1.5 m
Wing Area
91.7 ft² / 27.96 m²
Engine
160 hp (119.3 kW) Mercedes D.III 6-cylinder inline engine
Roland C.II PrototypeRoland C.II Schusta 28 – Lt. Otto Czermack Note the forward firing Lewis Gun mounted high to clear the propeller arc.Roland C.II – Black Stripes over Pre-Production PaintRoland C.II featuring a Shark MouthRoland C.IIa – Note the Larger RudderRoland C.III Prototype
Credits
Article written by Medicman
Edited by Stan Lucian & Ed Jackson
Illustrations by Ed Jackson
Herris, Jack. Roland Aircraft of WWI : a centennial perspective on Great War Airplanes. Charleston, SC: Aeronaut Books, 2014. Print.
Gray, Peter L., and Owen Thetford. German aircraft of the First World War. London: Putnam, 1970. Print.
Germany (1944)
Experimental VTOL Fighter – Paper Project
The bizarre looking Focke-Wulf Triebflügel fighter design. [luft46.com]During the war, German aviation engineers proposed a large number of different aircraft designs. These ranged from more or less orthodox designs to hopelessly overcomplicated, radical, or even impractical designs. One such project was a private venture of Focke-Wulf, generally known as the Triebflügel. The aircraft was to use a Rotary Wing design in order to give it the necessary lift. Given the late start of the project, in 1944, and the worsening war situation for Germany, the aircraft would never leave the drawing board and would remain only a proposal.
History
During the war, the Luftwaffe possessed some of the best aircraft designs and technology of the time. While huge investments and major advancements were made in piston engine aircraft development, there was also interest in newer and more exotic technologies that were also being developed at the time, such as rocket and jet propulsion. As an alternative to standard piston engine aircraft, the Germans began developing jet and rocket engines, which enabled them to build and put to use more advanced aircraft powered by these. These were used in small numbers and far too late to have any real impact on the war. It is generally less known that they also showed interest in the development of ramjet engines.
Ramjets were basically modified jet engines which had a specially designed front nozzle. Their role was to help compress air which would be mixed with fuel to create thrust but without an axial or centrifugal compressor. While this is, at least in theory, much simpler to build than a standard jet engine, it can not function during take-off. Thus, an auxiliary power plant was needed. It should, however, be noted that this was not new technology and, in fact, had existed since 1913, when a French engineer by the name of Rene Lorin patented such an engine. Due to a lack of necessary materials, it was not possible to build a fully operational prototype at that time, and it would take decades before a properly built ramjet could be completed. In Germany, work on such engines was mostly carried out by Hellmuth Walter during the 1930s. While his initial work was promising, he eventually gave up on its development and switched to a rocket engine insead. The first working prototype was built and tested by the German Research Center for Gliding (Deutsche Forschungsinstitut für Segelflug– DFS) during 1942. The first working prototype was tested by mounting the engine on a Dornier Do 17 and, later, a Dornier Do 217.
The Dornier Do 217 was equipped with experimental ramjets during trials. [tanks45.tripod.com]The Focke-Wulf company, ever keen on new technology, showed interest in ramjet development during 1941. Two years later, Focke-Wulf set up a new research station at Bad Eilsen with the aim of improving already existing ramjet engines. The project was undertaken under the supervision of Otto Ernst Pabst. The initial work looked promising, as the ramjets could be made much cheaper than jet engines, and could offer excellent overall flying performance. For this reason, Focke-Wulf initiated the development of fighter aircraft designs to be equipped with this engine. Two of these designs were the Strahlrohr Jäger and the Triebflügel. The Strahlrohr had a more conventional design (although using the word conventional in this project has a loose meaning at best). However, in the case of the Triebflügel, all known and traditional aircraft design theory was in essence thrown out the window. It was intended to take off vertically and initially be powered by an auxiliary engine. Upon reaching sufficient height, the three ramjets on the tips of the three wings would power up and rotate the entire wing assembly. It was hoped that, by using cheaper materials and low grade fuel, the Triebflügel could be easily mass-produced.
A model of the Triebflügel. This is how it may have looked if completed. [Wiki]
The Name
Given that these ramjet powered fighter projects were more a private venture than a specially requested military design, they were not given any standard Luftwaffe designation. The Triebflügel Flugzeug name, depending on the sources, can be translated as power-wing, gliding, or even as thrust wing aircraft. This article will refer to it as the Triebflügel for the sake of simplicity.
Technical Characteristics
Given that the Triebflügel never left the drawing board, not much is known about its overall characteristics. It was designed as an all-metal, vertical take-off, rotary wing fighter aircraft. In regard to the fuselage, there is little to almost no information about its overall construction. Based on the available drawings of it, it would have been divided into several different sections. The front nose section consisted of the pilot, cockpit, and an armament section for cannons and ammunition, which were placed behind him. Approximately at the centre of the aircraft, a rotary collar was placed around that section of the fuselage. Behind it, the main storage for fuel would be located. And at the end of the fuselage, four tail fins were placed.
A drawing of the Triebflügel’s interior. [luft46.com]This aircraft was to have an unusual and radical three wing design. The wings were connected to the fuselage while small ramjets was placed on their tips. Thanks to the rotary collar, the wings were able to rotate a full 360o around the fuselage. Their pitch could be adjusted depending on the flight situation. For additional stability during flight, the tail fins had trailing edges installed. The pilot would control the flying speed of the aircraft by changing the pitch. Once sufficient speed was achieved (some 240 to 320 km/h (150 to 200 mph)), the three ramjets were to be activated. The total diameter of the rotating wings was 11.5 m (37 ft 8 in) and had an area of 16.5 m² (176.5 ft²).
This unusual aircraft was to be powered by three ramjets which were able to deliver some 840 kg (1,1850 lb) of thrust each. Thanks to ramjet development achieved by Otto Pabst, these had a diameter of 68 cm (2.7 ft), with a length of less than 30 cm (0.98 ft). The fuel for this aircraft was to be hydrogen gas or some other low grade fuel. The estimated maximum speed that could be achieved with these engines was 1,000 km/h (621 mph). The main disadvantage of the ramjets, however, was that they could not be used during take-off, so an auxiliary engine had to be used instead. While not specifying the precise type, at least three different engines (including jet, rocket, or ordinary piston driven engines) were proposed.
In the fuselage nose, the pilot cockpit was placed. From there the pilot was provided with an overall good view of the surroundings. The main issue with this cockpit design wass the insufficient rear view during vertical landing.
Close up view of the Triebflügel landing gear assembly. [Secret Jets of the Third Reich]The landing gear consisted of four smaller and one larger wheels. Smaller wheels were placed on the four fin stabilizers, while the large one was placed in the middle of the rear part of the fuselage. The larger center positioned wheel was meant to hold the whole weight of the aircraft, while the smaller ones were meant to provide additional stability. Each wheel was enclosed in a protective ball shaped cover that would be closed during flight, possibly to provide better aerodynamic properties. It may also have served to protect the wheels from any potential damage, as landing with one of these would have been highly problematic. Interestingly enough, all five landing wheels were retractable, despite their odd positioning.
The armament would have consisted of two 3 cm (1.18 in) MK 103s with 100 rounds of ammunition and two 2 cm (0.78 in) MG 151s with 250 rounds. The cannons were placed on the side of the aircraft’s nose. The spare ammunition containers were positioned behind the pilot’s seat.
Final Fate
Despite its futuristic appearance and the alleged cheap building materials that would have been used in its construction, no Triebflügel was ever built. A small wooden wind tunnel model was built and tested by the end of the war. During this testing, it was noted that the aircraft could potentially reach speeds up to 0.9 Mach, slightly less than 1,000 km/h. The documents for this aircraft were captured by the Americans at the end of the war. The Americans initially showed interest in the concept and continued experimenting and developing it for sometime after.
In Modern Culture
The Triebflügel taking off in the movie. [marvelcinematicuniverse.fandom.com]Interestingly, the Triebflügel was used as an escape aircraft for the villain Red Skull in the 2011 Captain America: The First Avenger movie.
Conclusion
The Triebflügel’s overall design was unusual to say the least. It was a completely new concept of how to bring an aircraft to the sky. On paper and according to Focke-Wulf’s engineers that were interrogated by Allied Intelligence after the war, the Triebflügel offered a number of advantages over the more orthodox designs. The whole aircraft was to be built using cheap materials, could achieve great speeds, and did not need a large airfield to take-off, etc. In reality, this aircraft would have been simply too complicated to build and use at that time. For example, the pilot could only effectively control the aircraft if the whole rotary wing system worked perfectly. If one (or more) of the ramjets failed to work properly, the pilot would most likely have to bail out, as he would not have had any sort of control over the aircraft. The landing process was also most likely very dangerous for the pilot, especially given the lack of rear view and the uncomfortable and difficult position that the pilot needed to be in order to be able to see the rear part of the aircraft.
The main question regarding the overall Triebflügel design is if it would have been capable of successfully performing any kind of flight. Especially given its radical, untested and overcomplicated design, this was a big question mark. While there exist some rough estimation of its alleged flight performances, it is also quite dubious if these could be achieved in reality. The whole Triebflügel project never really gained any real interest from the Luftwaffe, and it is highly likely that it was even presented to them. It was, most probably, only a Focke-Wulf private venture.
Triebflügel Estimated Specifications
Rotating Wing diameter
37 ft 8 in / 11.5 m
Length
30 ft / 9.15 m
Wing Area
176.5 ft² / 16.5 m²
Engine
Three Ramjets with 840 kg (1,1850 lb) of thrust each
Empty Weight
7,056 lbs / 3,200 kg
Maximum Takeoff Weight
11,410 lbs / 5,175 kg
Climb Rate to 8 km
In 1 minute 8 seconds
Maximum Speed
621 mph / 1,000 km/h
Cruising speed
522 mph / 840 km/h
Range
1,490 miles / 2,400 km
Maximum Service Ceiling
45,920 ft / 14,000 m
Crew
1 pilot
Armament
Two 3 cm MK 103 (1.18 in) and two 2 cm (0.78 in) MG 151 cannons
Gallery
A rendition of how the Triebflugel may have looked had it been built. Illustration by Pavel ‘Carpaticus’ Alexe.
Credits
Article by Marko P.
Duško N. (2008) Naoružanje Drugog Svetsko Rata-Nemačka. Beograd.
D. Sharp (2015) Luftwaffe Secret Jets of the Third Reich, Dan Savage
Jean-Denis G.G. Lepage (2009) Aircraft of the Luftwaffe 1935-1945, McFarland and Company
J.R. Smith and A. L. Kay (1972) German Aircraft of the Second World War, Putham
The Ju 87A [warbirdphotographs.com]Prior to the Second World War, the Germans were experimenting with how to increase the accuracy of air bombing attacks. One solution was to use dive attacks, which greatly increased the chance of hitting the desired targets. By the mid-30s, a number of German aircraft manufacturing companies were experimenting with planes that could fulfill these dive bomb attacks. The Junkers Ju 87 proved to be the most promising design and would be adopted for service. The Ju 87 would become one of most iconic aircraft of the Second World War, being feared for its precise strikes, but also for its unique use of sirens for psychological warfare.
History
After the First World War, the Germans began experimenting with ideas on how to make aircraft more precise during ground attack operations. The use of conventional bombers that dispatched their payload from straight and level flight could effectively engage larger targets, such as urban centers, industrial facilities, infrastructure, etc. This method was less effective for destroying smaller targets, like bunkers or bridges. A dive-attack, on the other hand, provided a greater chance of hitting smaller targets and, to some extent, reduced the chance of being shot down by ground based enemy anti-aircraft fire. This concept of dive-attack aircraft would be studied and tested in detail by the Germans during the 1930s. These aircraft would be known as Sturzkampfbomber (dive-bomber), but generally known as Stukas.
The development of such aircraft was greatly hindered by the prohibitions imposed by the Treaty of Versailles. To overcome this, some German companies simply opened smaller subsidiaries in other countries. In the case of the Junkers, a subsidiary company known as Flygindustri was opened in Sweden. There, they developed a K 47 two-seater fighter in 1929. It was tested for the role of dive-bomber and proved successful. But its price was too high for the German Luftwaffe to accept, so it was rejected.
The Junkers K 47 was a two-seater fighter from 1929. While showing to possess good dive-attack characteristics, due to its price, it was not adopted for service. [Wiki]As a temporary solution, the Germans adopted the He 50 in 1932. The following year, a more comprehensive test of the dive-bombing concept was undertaken at airbase Juterbog-Damm. During these trials, Ju-52 bombers were used. The overall results were disappointing, thus development of a completely new dedicated design was prioritized by the Germans. For this, Luftwaffe officials placed an order with all aircraft manufacturers to present their models for the dive-bomber competition.
In late 1933, the Junkers dive-bomber development project was carried out by engineer Herman Pohlmann. He stressed the importance of an overall robust aircraft design in order to be able to withstand steep diving maneuvers. Additionally, it should have had fixed landing gear and be built using all-metal construction.
The next year, a fully completed wooden mock-up with inverted gull wings and twin tail fins was built by Junkers. Officials from the German Aviation Ministry (Reichsluftfahrtministerium RLM) inspected the mock-up during late 1934, but they were not impressed and didn’t place a production order. Despite this, Junkers continued working on the project. Junkers soon began construction of a full scale prototype. Due to many delays with the design, construction of the project dragged into October 1935. The first prototype received the Ju 87 V1 designation, bearing serial number 4921. Somewhat surprisingly, it was powered by a 640 hp Rolls-Royce Kestrel 12 cylinder engine. The first test flight was completed in September 1935 by test pilot Willi Neuenhofen. While the first flight was generally successful, the use of a foreign engine was deemed unsatisfactory and it was requested that a domestic built engine be used instead. The V1 prototype would be lost in an accident when one of the twin tail fins broke off during a dive test near Dresden. Both the pilot Willi Neuenhofen and the second passenger, engineer Heinrich Kreft, lost their lives. The examination of the wreckage showed that the fin design was too weak and thus had to be replaced with a simple conventional tail fin.
The V1 prototype could be easily identified by its twin tail fin design. [warbirdphotographs.com]Ju 87 V2 (serial number 4922 and with tail code D-UHUH (later changed to D-IDQR) was built with the 610 hp Jumo 210 A engine and had a redesigned tail fin. Another addition was the installation of special slats that could be rotated at 90° forward, perpendicular to the underside of the wing, acting as dive brakes. The V2 also received a specially designed bomb release mechanism, meant to avoid accidentally hitting the lowered radiator and the propeller. When the pilot activated the bomb release during a dive, the specially designed cradle would simply swing forward. In essence, this catapulted the bomb safely away from the plane while still maintaining its trajectory toward the target. There were a number of delays with the redesign of the airframe, which led to V2’s first flight being made during late February 1936. While the test flight was successful, the Luftwaffe officials showed some reluctance with regards to the project, given the fate of the first prototype. Nevertheless, the Ju 87, together with the He 118, Ha 137 and Ar 81, were used in a dive-bomber competition. The initial results favored the Heinkel, but when the He 118 was lost during one of its test flights together with the engine problems, the RLM proclaimed the Ju 87 as the winner.
The unsuccessful He 118 aircraft. [Wiki]The Ju 87 V2 prototype. [warbirdphotographs.com]Winning the competition for the new dive-bomber design, Junkers was instructed to build more prototypes to improve the overall performance of the Ju 87. The V3 (serial number 4923 and designation D-UKYQ) received a number of modifications. It had an enlarged tailfin, added counterweights on the elevators, a modified landing gear, and a redesigned engine cowl to improve forward visibility. The first test flight was made in March of 1936.
The V4 (serial number 4924 and with D-UBIP) was further modified by once again increasing the size of the tailfin, adding forward firing machine guns, a rear defensive machine gun, and again redesigning the front engine compartment. It was powered by the Jumo 210 Aa engine. It was flight tested for the first time in June 1936. During its test flight, the maximum cruising speed achieved was 250 km/h (155 mph). The RLM would become increasingly concerned about the Ju 87 design, as this cruising speed was the same as that of the older He 50. Despite this, the handling and resilience of the whole airframe were deemed satisfactory. The V4 prototype would later serve as the base for the A-0 pre-production series. The last prototype, V5 (serial number 4925), was built in May 1936. It was built to test the installation of the DB 600 and Jumo 210 engines.
The V4 prototype, which served as base of the A-0 pre-production series. In addition, it was the first Ju 87 aircraft to see real combat action during the Spanish Civil War. [warbirdphotographs.com]
The Ju 87 ‘Anton’ Introduction
Following the success of the prototype series, the RLM officials issued orders for more Ju 87 aircraft. This would lead to a small production run of between 7 to 10 aircraft of the Ju 87A-0 pre-series aircraft (A for Anton, according to the German phonetic alphabet). While the first A-0 aircraft were to be built starting in November 1935, due to a number of delays, the actual production began in the spring of 1936. Following a series of tests conducted on the A-0 aircraft at the end of 1936, it was determined that these planes, equipped with the Jumo 210 Aa engine, were underpowered. A number of the A-0 aircraft would receive a new 680 hp Jumo 210 D engine as an upgrade. The A-0’s rear fuselage was also lowered to provide the rear gunner with a better firing arc. For the radio equipment, two ‘V’ shaped antennas were placed around the cockpit.
Further development led to the Ju 87A-1, which was powered by the Jumo 210 D as standard. The A-1 series was able to carry one 250 kg (550 lbs) bomb in its standard two man crew configuration. Alternatively, it could carry one 500 kg (1100 lbs) bomb but, in this case, the rear machine gunner had to be left behind.
The last version of the series was the Ju 87A-2. It was slightly improved by adding better radio equipment. In addition, the engine performance was improved, along with a new two-stage compressor, and a new propeller.
Technical Characteristics
The Ju 87A was designed as a single-engined, twin-seat all metal dive bomber. Its fuselage was built by connecting two oval-shaped sections with a simple structure design. The longerons consisted of long shaped strips which spanned across the longitudinal direction of the aircraft. These had a ‘U’ shape which was connected to the duralumin skin by rivets.
For construction of the Ju 87’s wings, Junkers engineers employed the doppelüger (a double wing construction). This meant that the full-span ailerons were hinged near the trailing edge of the wings. Another feature of the wings was that they had an inverted gull design. This was done intentionally by the Junkers engineers in an attempt to provide the crew members with the best possible all around visibility. The Ju 87 fuselage and wings were covered with a combination of duralumin and magnesium alloy sheeting. While the V1 prototype was equipped with twin tail fins, the A-series was equipped with a more orthodox tail design. The tailplanes had a rectangular shape, while the rudder had a square shape.
Rear view of the Ju 87A [asisbiz.com]The landing gear was fixed. It consisted of two larger front wheels, with one smaller tailwheel to the rear. The front landing gear and wheels were covered in large protective fairings, sometimes known as “spats.” This arrangement would prove to be problematic, and would later be replaced with a much simpler design.
The Ju 87 had a distinguishable fixed landing gear, protected by a larger housing. This design would be simplified in later version. [asisbiz.com]The Ju 87 engine was mounted specifically to provide easy access for replacement or maintenance. It was powered by an inline Jumo 210 D water cooled engine, with a variable pitch propeller with a 3.3 m diameter. The fuel capacity was 480 liters, placed in two tanks. The fuel tanks were located in the center part of the curved wings.
The Ju 87 had a large cockpit where the pilot and the rear gunner were positioned in a back-to-back configuration. The center of the canopy assembly was reinforced by a durable section of cast magnesium, meant to provide better structural integrity. The cockpit was also protected with a fire-resistant asbestos firewall. On the A-series, the pilot was responsible for operating the radio equipment. This task would be allocated to the rear gunner in later versions. The radio equipment consisted of a FuG VII radio receiver and transmitter.
The Ju 87A-1 was armed with one forward mounted 7.92 mm MG 17 and a rear positioned MG 15, also firing 7.92 mm, fitted on a flexible mount. The offensive armament consisted of either a 250 kg or 500 kg bomb (550 to 1100 lbs). When the larger bomb was used, the rear crew member had to be left behind. A small number of aircraft were equipped with bomb racks for four 50 kg (110 lbs) mounted under the wings. These were actually used for training purposes, as the bombs were actually made of concrete.
Diving Operation
The Ju 87 pilot would commence the dive-bombing run once the target was identified. The target would be located through a bombsight which was placed in the cockpit floor. The attack would usually be carried out from an altitude of less than 4,600 meters. The aircraft would then be rolled around by the pilot until it was upside down. The Ju 87 would then engage its target at an angle of attack of 60 to 90°, with a speed of 500 to 600 km/h (310-370 mph). During these dive-bombing runs, there was a chance the pilot could temporarily lose consciousness due to extensive G-forces. If the pilot was unable to pull up, a ground collision was a strong possibility. To avoid this, the Ju 87 was equipped with automatic dive brakes that would simply level out the plane at a safe altitude. Once the plane reached a level flight, the brakes would then disengage. The Ju 87 was also equipped with warning lights that informed the pilot when it was time to release the bomb.
Germans conducted extensive research to determine how much G-force a pilot could endure without any medical problems. The testing revealed that the pilot could overcome a 4G force without problems. At 5G , the pilot would experience blurred vision. The maximum G-forces were noted to be 8.5 G but only for three seconds. Any more could lead to extensive injuries or even death.
Illustration of a Ju 87 dive-attack run. Source Pinterest
Organization
The Ju 87 were used to equip the so-called Sturzkampfgeschwader or simply StG (dive-bomber flight unit). The StG was divided into three Gruppen (groups). Each of these groups was further divided into three Staffel (squadrons).
In Combat
The Ju 87 saw its first combat action during the Spanish Civil War that lasted from 1936 to 1939. The Germans saw this war as the perfect place to test their new aircraft designs. For this reason, one V4 prototype was secretly disassembled and transported on a passenger ship to Spain in August 1936. It was part of the experimental unit (Versuchskommando) VK/88 (or VJ/88, depending on the source) of the Condor Legion. The overall performance or even the use of this aircraft is generally unknown. During this conflict, it received the designation 29-1. It may have taken part in the Battle of Bilbao in June of 1937, after which it was shipped back to Germany.
In early 1938, three more aircraft of the A-1 series were shipped to Spain. These received the 29-2, 29-3, and 29-4 designations. They were given to the 1st Staffel of Sturzkampfgeschwader 162 (dive bomber wing). While only three aircraft were used by this unit their original designations were often replaced with higher numbers in an atempt to decive the enemy. The initial pilots of these aircraft were Ernst Bartels, Hermann Hass, and Gerhard Weyert. The Germans would replace them with new crew members after some time, in the hope of increasing the number of pilots with experience operating the aircraft under combat situations.
Their initial base of operations was an airfield near Zaragoza, Spain. There were some problems with the forward landing gear covers, which would dig into the ground on the sandy soil of the airfield. To resolve this issue, the crews simply removed them. The use of a larger 500 kg bomb required the removal of the rear gunner, so the smaller 250 kg bomb load was more frequently used.
In March 1938,, the three Ju 87s attempted to attack retreating Spanish Republican units at the Aragon with somewhat limited success. The attacks were less successful, mainly due to the inexperience of the pilots. From July 1938 on, the Ju 87 showed more promising performance during the Spanish Republican failed counterattack at the Ebro River and Mequinenza. By October, all three Ju 87 As were shipped back to Germany.
A Ju 87A during the Spanish Civil War [Wiki]The overall performance of the A-series was deemed insufficient for combat operations early on. This, together with the fact that the improved Ju 87B version was becoming available in increasing numbers, leading to a withdrawal of the A version from service. These would be reallocated to training units, and would be used in this role up to 1944.
The Ju 87A would see only limited combat service, being mostly allocated to training units [warbirdphotographs.com]
In Hungarian Service
During the war the Germans provided their Hungarian ally with four Ju 87A aircraft. These were used mostly for crew training in later stages of the war.
Hungarian Ju 87A [Hungarian Air Forces 1920-1945]
Production and Modifications
Production of the Ju 87 ended by the summer of 1938. By that time, some 262 were built by the Junkers factories located in Dessau (192) and Bremen (70). These numbers are according to M. Griehl (Junkers Ju 87 Stuka). Author D. Nešić (Naoružanje Drugog Svetsko Rata-Nemačka), on the other hand, notes a number of 400 aircraft being built.
The main versions were:
Ju 87 Prototype series – Five prototypes were built and used mostly for testing.
Ju 87A-0 – A small pre-production series.
Ju 87A-1 – Main production version.
Ju 87A-2 – Slightly improved A-1 aircraft.
Conclusion
While the Ju 87A fulfilled the role of dive-bomber well, it was shown to be inadequately developed to meet military requirements. For this reason, it was mainly issued for crew training. Its main success was that it provided the German with an excellent base for improvement and development of further aircraft. It also provided the German pilots with valuable experience in such dive-bombing flights.
Ju 87A-1 Specifications
Wingspans
45 ft 3 in / 13.8 m
Length
35 ft 4 in / 10.78 m
Height
12 ft 9 in / 3.9 m
Wing Area
104 ft² / 31.9 m²
Engine
Junkers Jumo 210D 680 hp engine
Empty Weight
5,070 lbs / 2,300 kg
Maximum Takeoff Weight
7,500 lbs / 3,400 kg
Fuel Capacity
480 liters / 127 US gallons
Maximum Speed
200 mph / 320 km/h
Cruising speed
170 mph / 275 km/h
Range
620 miles / 1,000 km
Maximum Service Ceiling
22,970 ft / 7,000 m
Crew
One pilot and the Rear Gunner
Armament
One forward mounted 7.92 mm MG17 and one 7.92 mm MG15 positioned to the rear
One 550 lb (250 kg) bomb for two-seaster
Or one 1100 lb (500 kg) bomb in the single-seater configuration.
Gallery
Illustrations by Carpaticus
Ju 87A with an unusual winter camouflageJu 87A-1 from the Dive bomber school 1, operated during winter 1940-1941Ju 87A used for pilot training in late 1939Ju 87 A-1 1st Staffel of Sturzkampfgeschwader 162 during the Spanish Civil War
Credits
Article by Marko P.
Edited by Stan L. & Ed J.
Illustrations by David Bocquelet & Carpaticus
M. Griehl (2006) Junkers Ju 87 ‘Stuka’, AirDOC.
M. Guardia (2014) Junkers ju 87 Stuka, Osprey Publishing
D. Nešić (2008). Naoružanje Drugog Svetsko Rata-Nemačka. Tampoprint S.C.G. Beograd.
D. Monday. (2006). The Hamlyn Concise Guide To Axis Aircraft OF World War II, Bounty Books.
Z. Bašić (2018) Građanski Rat U španiji 1936-1939, Čigoja Štampa.
G. Sarhidai, H. Punka and V. Kozlik. (1996) Hungarian Air Forces 1920-1945, Hikoki Publisher
Nazi Germany (1936)
Shipborne and coastal reconnaissance aircraft – 98~118 Built
The He 114 Source: www.warbirdphotographs.com
In the mid-thirties, the German Ministry of Aviation (Reichsluftfahrtministerium – RLM) tasked the Heinkel company with developing a replacement for the He 60 shipborne and reconnaissance aircraft. While Heinkel fulfilled the request by building the He 114, its overall performance was deemed insufficient for German standards.
History
During the early thirties, the He 60 was adopted for service as the main German shipborne and coastal reconnaissance aircraft. As it was considered outdated, in 1935, the RLM issued to Heinkel a request for a new shipborne and coastal reconnaissance aircraft that was to replace the He 60. The next year, two prototypes were completed. While it was originally planned to test these aircraft with the BMW 132 engine, due to lack of availability, this was not possible. The first prototype (with D-UBAM marking) made its maiden flight in September 1936. It was powered by a Daimler Benz DB-600A which gave out 900 hp. The test results of the first flight were disappointing, as it proved difficult to control on the water but also in the air. The second prototype, V2 (D-UGAT), powered by a 740 hp Jumo 210 E, made its first flight in December 1936. It was used to test the catapult launching capabilities of this aircraft. It had some modifications in comparison to the first prototype, like having a larger tail and redesigned floats. Despite some improvements, the catapult launch testings from the Gneisenau showed that the He 114 was not suited for this role.
Despite not having a promising start, further prototypes were ordered. The V3 (D-IDEG) prototype was powered by an 880 hp BMW 132 K (or D, depending on the source) engine. The floats were once again redesigned and the pilot had a better-glazed shield. This aircraft was tested in April 1937 with similar performance as previous versions.
V4 (D-IOGD) made its maiden test flight in August 1937. It had many modifications in order to improve its performance. The wing’s edges were redesigned, new floats were used and it was also fitted with machine gun armament. V5 (D-IQRS) had new improved floats which enabled it to take-off even from ice. While most sources mention only five prototypes, some note that there were two more. The V6 and V7 prototypes were tested with similar equipment and were armed with two machine guns, one firing through the propeller and the second mounted to the rear. Additional armament tested consisted of two 50 kg (110 lb) bombs.
A side view of the V4 prototype, during a test flight. Source www.warbirdphotographs.com
Technical characteristics
The He 114 was designed as a single-engine, all-metal, twin crew biplane aircraft. It had a monocoque oval-shaped fuselage design. It was powered by one BMW 132K 960 hp nine-cylinder radial engine. The fuel load consisted of 640 l.
The He 114 BMW 132K 960 hp nine-cylinder radial engine. Source: www.warbirdphotographs.com
Somewhat unusual for biplanes of the era, the lower wings were much smaller than the upper ones. They had a half-elliptical design and were thicker than the upper wings. The upper wing was connected to the fuselage by two ‘N’ shaped struts. There were also two ‘Y’ struts connecting the lower and the upper wings. The upper wing was constructed using three parts with two ailerons. The upper wing could, if needed, be folded to the rear. The landing gear consisted of two floats which could also act as auxiliary fuel storage tanks with 470 l each.
On later models, the floaters were used as auxiliary fuel tanks. Source www.warbirdphotographs.com
The crew consisted of the pilot and the rear positioned machine gunner/observer. The armament consisted of one MG 15 7.92 mm (0.31 in) machine gun placed to the rear. The ammunition load for this machine gun was 600 rounds. Additionally, there was an option to externally mount two 50 kg (110 lb) bombs.
Close up view of The He 114 pilot control table. Source: www.warbirdphotographs.com/luftwaffephotos
Further development
Despite being shown to have poor performance, a small production run was made by Heinkel. Some 10 (or 6 depending on the source) aircraft of the A-0 series, together with 33 of the A-1 series would be built. The only difference was the use of a larger rear tail design on the He 114A-1 series. The small number of He 114 built were given to various test units and flight schools, where its performance was often criticized by all. During its introduction to service, the much more promising Ar-196 was under development, but it would need some time until production was possible. As a temporary solution, the Luftwaffe officials decided not to retire the He 60 from service yet. Heinkel was informed that, due to the He 114’s overall poor performance, it would not be accepted for service and that it would be offered for export if anyone was interested. For this reason, Heinkel developed the He 114A-2 series. The He 114A-2 had a reinforced fuselage, floats that could be used as fuel storage tanks, and, additionally, it was modified to have catapult attach points. The He 114A-2, while tested, was not operated by the Luftwaffe, and it was used for the export market.
The following B-series (including B-1 and B-2) were actually just A-2 planes with some slight improvements, meant primarily for export. The history of the C-series is somewhat unclear, as it appears to be specially developed for Romania. It was much better armed, with either two 20 mm (0.78 in ) MG 151 cannons, two 13 mm (0.51 in) MG 131 heavy machine guns, or even two MG 17 7.92 mm (0.31 in) (the sources are not clear) placed inside the lower wings. Some sources also mention that additional machine guns were installed inside the engine compartment and could be fired through the propeller. Additionally, it appears that its fuselage was modified to be able to carry two additional 50 kg (110 lb) bombs. The rear positioned MG 15 was unchanged. This version also had a new Junkers type 3.5 m diameter propeller. The floaters were also slightly redesigned and it received smoke screen trovers. Additionally, to provide better stability while positioned near shore, a small anchor could be realized.
Operational use
Despite not being accepted by the Luftwaffe, due to the Kriegsmarine’s (German war navy) lack of sufficient seaplanes, some He 114 had to be used for this purpose. The distribution of the He 114 began in 1938 when the 1./Küstenfliegergruppe 506 was equipped with this aircraft. In 1939, it was 43equipped with the older He 60, as these proved to be better aircraft. Some German ships, like the Atlantis, Widder, and Pinguin, received these aircraft. During their use, the He 114 floater units proved to be prone to malfunctions. These were reported to be too fragile and could easily be broken down during take-off from the sea during bad weather.
While designed to be able to take-off from German ships, the He 114 construction was not strong enough and was prone to breakdowns with many aircraft being lost this way. Source /www.warbirdphotographs.com/luftwaffephotosDespite intended as a replacement of the He 60 this was never implemented due to He 114 poor performance. Source www.warbirdphotographs.com/luftwaffephotos
A group of 12 He 114 C-1 aircraft that were to be sold to Romania were temporarily allocated to the 2nd Squadron of the 125th Reconnaissance Group (2/125 Aufkl.Sta.). These units operated in the area of Finland’s shore. When the Bv 138 became available in sufficient numbers, the He 114 C-1 was finally given to Romania.
Foreign use
While the He 114 failed to get any large production orders in Germany, it did see some export success. These included Denmark, Spain, Romania and Sweden. The B-series was sold, which was more or less a copy of the A-2 series.
In Danish service
The Danish use of the He 114 is not clear. Depending on the source, there are two versions. In the first, Denmark managed to buy 4 He 114 aircraft and even ordered more, but the German occupation stopped any further orders. In the second, while Denmark wanted to buy some He 114, nothing came of it, once again due to German occupation.
In Spanish service
During 1942, Spain obtained some 4 He 114s from the Germans. In Spanish service, these were known as HR-4. Despite their obsolescence and lack of spare parts, these would remain in use up to 1953.
Small numbers of He 114 were supplied to Spanish State during 1942. Source: www.warbirdphotographs.com
In Romanian service
Romania received a group of 12 He 114 in 1939. During the war, the number would be increased to 29 in total. These would be extensively used to patrol the Black Sea. At the end of the war, these were captured by the Soviets, who confiscated them. Some would be returned to Romania in 1947, which would continue to use them up to 1960, when they were scrapped.
The He 114 in Romanian Service.Source: www.warbirdphotographs.com/luftwaffephotos
In Swedish service
Sweden bought some 12 He 114 in March 1941. In Swedish service, these would be renamed to S-12. Despite being an unimpressive design and prone to malfunction, the Swedish used them extensively during the period of 1941 to 1942, with over 2054 flight missions. They would remain in service up to 1945, with six aircraft being lost in accidents.
One S-12 (as it was known in Sweden) of 12 in total was sold to Sweden. Source: www.warbirdphotographs.com/luftwaffephotos
Production
Despite its poor performance, Heinkel undertook a small production of the He 114. The number of produced aircraft ranges from 98 to 118 depending on the source.
He 114 Prototypes – Between 5 to 7 prototypes were built
He 114 A – Limited production series
He 114 B – Export version of the A-series
He 114 C – Slightly improved version with stronger armament
Operators
Germany – Small numbers of these aircraft were operated by the Luftwaffe and Kriegsmarine, but their use was limited
Denmark – Possibly operated four He 114 before the German occupation
Spain – Bought four He 114, and operated them up to 1953
Sweden – Bought 12 He 114 in March 1941, which remained in use until 1945
Romania – Operated 29 He 114, with the last aircraft being scrapped in 1960
Surviving aircraft
While there are no complete surviving He 114s various parts and wrecks have been found over the years. Parts of one wreck were found in lake Siutghiol near Mamaia, on the Romanian Black Sea coast, in 2012. There is a possibility that the wreck of another lays in a lake near Alexeni as well.
Conclusion
The He 114 was an unsuccessful design that failed to gain any larger production orders in Germany. It had difficult controls both in the air and on the water. While it would see some limited service with the Luftwaffe, most would be sold abroad, where some were used up to the ’60s.
He 114C-1 1./SAGr.125 -Baltic Area 1941He 114A-2 1.-KuFlGr-506 Devenow 1938He 114A 1./SAGr.125 Baltic Area 1941He 114B in Romanian Service Circa 1943
Sources
D. Nešić (2008), Naoružanje Drugog Svetskog Rata Nemačka Beograd
M. Griehl (2012) X-Planes German Luftwaffe Prototypes 1930-1945, Frontline Book.
S. Lonescu and C. Craciunoi, He 114, Editura Modelism
Jean-Denis G.G. Lepage Aircraft Of The Luftwaffe 1935-1945, McFarland and Company.
Ferenc A. and P. Dancey (1998) German Aircraft Industry And Production 1933-1945. Airlife England.
https://www.cugetliber.ro/stiri-eveniment-hidroavion-din-al-doilea-razboi-mondial-descoperit-in-lacul-tasaul-201060
Nazi Germany (1938)
Transport plane – 13 built with 4 uncompleted aircraft
The Blohm und Voss Bv 222 was the largest World War Two flying boat that ever reached operational service. Even though it started as a civilian project, due to wartime demand, it was quickly put into service with the Luftwaffe during the Second World War.
The Bv 222 during a flight over Germany. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
The History of Blohm & Voss
The Blohm & Voss Schiffswerft und Maschinenfabrik (shipbuilding and engineering works) company was founded in 1877 by Hermann Blohm and Ernst Voss. After World War I, Blohm & Voss continued production of ships, but also reoriented to the production of aircraft (especially flying boats). In the following years, the company managed to cooperate with Lufthansa (the German Passenger Airline) and later even with the Luftwaffe.
Early on in the development and production of their first aircraft, they received the ‘Ha’ designation (standing for Hamburger Flugzeugbau, the factory’s station at Hamburg). This would be later replaced by ‘Bv’ (also sometimes marked as ‘BV’), which represented the owner’s initials. Blohm & Voss would build a number of flying boat designs like the Ha 138, Ha 139, Bv 222 and BV 238. During the war, the company was also engaged in developing a number of glide bombs like the Bv 143 and Bv 246 Hagelkorn.
The first prototype of the Bv 222, V1 (reg. D-ANTE), was briefly tested by Lufthansa before being taken over by the Luftwaffe. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
The Lufthansa Request
In 1937, Lufthansa opened a tender for long-range passenger transport flying boats. The requirements for this tender included that the aircraft had to be able to travel from Berlin to New York in 20 hours. A few well known German aircraft manufacturers responded to this tender, including Heinkel, Blohm & Voss and Dornier. Whilst both Heinkel and Dornier had enough experience in designing seaplanes, Blohm & Voss was relatively new to this. One of the first Blohm & Voss seaplane designs was the Ha 139. While only a few were built, the company gained valuable experience in building such aircraft. The man responsible for designing the flying boat was Dr. Ing. Richard Vogt (chief designer at the Blohm & Voss) and his assistant R. Schubert.
All three aircraft manufacturers presented their models. Heinkel submitted the He 120 (renamed later to He 220), Dornier came up with the Do 20 and Blohm & Voss proposed the Ha 222 (later renamed to Bv 222). The Lufthansa officials, after detailed considerations, decided that the best aircraft was the Bv 222. An official contract between Lufthansa and Blohm & Voss was signed on 19th August 1937 for three aircraft to be built.
By the end of 1937, the Lufthansa officials requested improvements to the Bv 222. One of these regarded the number of passengers. It now had to accommodate at least 24 passengers on shorter trips and 16 during long voyages across the Atlantic.
Change into a Military Project
The design work on the new aircraft began in January of 1938 and lasted almost a year. This was mainly due to the huge task and the inexperience of Blohm & Voss in designing such large aircraft. Nevertheless, the construction of the first Bv 222 V1 prototype began in September 1938, followed a few weeks later by the V2 and V3 prototypes. Work on the Bv 222 was slow and it dragged on into 1939 and 1940. By this time, due to the outbreak of war, a shortage of skilled labour and the decision to concentrate on the Bv 138, the Bv 222 had low priority.
In July 1940, Blohm & Voss presented a mockup of the Bv 222 exterior and interior to Lufthansa officials. They were generally satisfied but demanded some changes. In early August, despite receiving Lufthansa approval, the Bv 222 project was actually slowly being taken over by the Luftwaffe for its own use.
By the end of August 1940, the Bv 222 V1 prototype was completed, and many taxi and loading tests were carried out. The first test flight was piloted by Captain Helmut Wasa Rodig on 7th September 1940. While the general flight performance was deemed satisfactory, there were some issues, such as instability during horizontal flights and staggering from one side to another when floating on water. While still under development and testing for civilian use, the Bv 222 V1 received the registration D-ANTE.
The Bv 222’s cockpit. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
Technical Characteristics
The Bv 222 was designed as a six-engined, high wing, flying transport plane. Unfortunately, the sources do not provide us with more precise information about its construction. This is mostly due to the small number of aircraft built.
While the sources do not mention if it was built using only metal or mixed construction, the Bv 222’s fuselage was covered with 3-5 mm thick anticorrosive metal framework. Its large size made it possible to build two floors. The upper floor was designed for the crew of the plane. The lower floor was initially designed to accommodate civilian seats, but as the Bv 222 was put into military service, this area was used to store equipment or soldiers. A large door was provided to access the lower floor.
The wings were constructed using a huge tubular main spar. These were used to provide additional room for spare fuel and oil tanks. The fuel was stored in six fuel tanks with a total capacity of 3,450 litres. Four outboard stabilising floats (two on each side) were carried on the wings. These would split into two halves and retract into the wing. The purpose of these stabilising floats was to stabilise the plane during landings on water.
The crew number varied between each aircraft. It usually consisted of two pilots, two mechanics, a radio operator and, depending on the number of guns installed, additional machine gun operators.
The Bv 222 was initially powered by six Bramo 323 Fafnir 1000 hp strong radial engines. Other engines, for example Jumo 207C, were used later during the production run.
The defensive armament varied between each plane and usually consisted of several different machine guns or cannons. The following different types of weapons are known to have been used: 7.92 mm (0.31 in) MG 81, 13 mm (0.51 in) MG 131 and 20 mm (0.78 in) MG 151.
The Bv 222 V2 prototype from the rear. Here we can also see the rear defense turret. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
The Bv 222 (V4, V5, V6 and V8) were equipped with the most advanced electronic equipment that the Germans had, such as the FuG 200 surface search radar, FuG 101 A radio altimeter, FuG 25 A friend or foe identification system and the FuG 16 command guided target approach system. The radio equipment used on these four were the Lorenz VP 257 and the Lorenz VP 245 transoceanic relay sets.
First Military Transport Flight Operations
By the end of 1940, Bv 222 V1 was mostly used for testing and correcting any issues. By December of 1940, due to the winter and bad weather, further tests were not possible. As Bv 222 V1 was fully operational and enough fuel was stored, it was deemed a waste of resources to simply wait for the arrival of spring. For this reason, Luftwaffe officials proposed for the Bv 222 V1 to be used in a military transport operation between Hamburg and Kirkenes (Norway). For this operation, the Bv 222 V1 was modified by adding a large side hatch door. During this operation, Bv 222 V1 received a military camouflage paint scheme and received the registration number CC+EQ. By mid August 1941, the Bv 222 V1 achieved a total of 120 hours flight, with some 65 tonnes of cargo and 221 wounded soldiers transported. This mission was a success and the Bv 222 V1 proved to be an effective transport plane.
Bv 222 V5 somewhere in the Mediterranean. Note the left wing’s outboard stabilizing floats designed to provide better balance when floating on water. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
After a period of needed general overhaul and repair, Bv 222 V1 was set for a new transport mission, this time to support the DAK-Deutsches Afrikakorps (German Africa Corps). The main bases of operation were from Athens to Derna in Africa. The mission was carried out from 16th October to 6th November 1941. In total, seventeen flights were carried out, with 30 tonnes of supplies and 515 wounded soldiers and personnel transported. As Bv 222 V1, at this time, was not equipped with any defensive armament, two Me 110s were provided for its escort. While it was a prototype plane, no defensive armament was installed. But, after several encounters with the British Air Force in the Mediterranean, the need for defensive armament became apparent. At this stage, the Bv 222 was lucky, as it managed to emerge from these engagements in one piece. It even managed to survive the attack of three British Beaufighters on a flight from Taranto to Tripoli.
During these transport flights, the improved Bramo 323 engines (which replaced the earlier BMW 132) achieved a solid but satisfactory overall flight performance. But the Bramo 323 engines were deemed prone to malfunctions.
Future Service within the Luftwaffe
During the winter of 1941/1942, Bv 222 V1 was again returned to Blohm & Voss for more repairs but also for fitting its first defensive armament. The armament consisted of several 7.92 mm (0.31 in) and 13 mm (0.51 in ) machine guns. Note that the information about armament in this article is taken from H. J. Nowarra’s book “Blohm and Voss Bv 222”, but other authors state that different armament was used. One MG 81 was placed in the nose, four more MG 81s were placed in the fuselage and two additional DL 131 turrets with MG 131s were placed in the upper fuselage. At the same time, Bv 222 V1 received a new registration code, X4+AH. It was attached to Luft-Transport-Staffel 222 (short LTS 222) which mainly operated in the Mediterranean. The LTS 222 official squadron marking was a Viking longship and it is probably for this reason that the Bv 222 were nicknamed ‘Wikings’.
The Bv 222 V8 placed on a ramp, possibly for repairs. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
During 1942, LTS 222 was reinforced with four newly built Bv 222s of the A-series. V4 (reg. num. X4+DH) was received in mid April, V5 (reg. num. X4+EH) on 7th July, V6 (reg. num. X4+FH) on 21st August and V8 (reg. num. X4+HH) in late September. These four were provided with defensive armament consisting of two DL 151 turrets, each armed with an MG 151 in the upper fuselage, one MG 131 in the nose position and two MG 81 on the fuselage sides.
After many extensive and dangerous transport missions, Bv 222 V1 finally ran out of luck, and was lost in a tragic accident in early 1943. While on a flight to Athens, due to Allied air raids, the pilot tried to land on water. Because of the total darkness, the pilot was unable to see a half sunken wreckage, which damaged the plane so much that it sank in only a few minutes. Luckily, the crew was safely evacuated.
Bv 222 V2 made its first test flight on the 7th August 1941. It was initially used by the Erprobungsstelle Travemünde for testing and improvements. It had its bottom fuselage redesigned to provide better stability when floating in water. In addition, two reserve thrust propellers were attached to each middle engine on both sides, which improved flight performance. It was not used by LTS 222 but was instead given to the Fliegerführer Atlantik unit. As this unit name suggests, Bv 222 V2 (which later included other Bv 222s) was used to patrol the Atlantic. Its main base of operations was the city of Biscarrosse in occupied France. Bv 222 V2 would remain in use up to the war’s end, when it was captured by the Allied forces in May 1945.
The Bv 222 V3 prototype had a much shorter operational service life. It made its first test flight on the 28th November 1941. It was lost on the 30th June 1943 while on a patrol mission across the Atlantic.
Bv 222 V4 was initially used in a transport mission above the Mediterranean. On 10th December 1942, it was damaged by Allied raids. After the necessary repairs, it would be used for the remainder of the war on patrol missions across the Atlantic. In October 1943, it, together with Bv 222 V2, managed to shoot down a British Avro Lancaster bomber over the ocean. The circumstances of this event are not clear even to this day. Bv 222 V4 was sunk by its crew in May 1945 at Kiel.
Most Bv 222s were powered by six 1000 hp Bramo 323 engines. These were later replaced with Jumo 207Cs. http://www.warbirdphotographs.com/luftwaffephotos/index.html
V5 was used for transport of materiel and men above the Mediterranean, until the loss of Bv 222 V1. After that, it was recalled to Germany to be structurally strengthened and equipped with stronger defensive armament. From April 1943, it was used in Atlantic patrol missions, until it was shot down by the Allies in June the same year.
V6 was shot down by the British shortly after it was attached to LTS 222. Bv 222 V8 also had a short operational life, as it was lost in action to Allied fighters on 10th December 1942.
It is interesting to point out that, during the Bv 222’s service in the Mediterranean, the British would attack these aircraft only when they were transporting ammunition and supplies to Africa, but they would not attack them on their way back to Europe as they would be transporting wounded soldiers.
After construction of the first three prototypes, the next four aircraft were reclassified as the A-series (V4, V5, V6 and V8). Interestingly, these would also retain their prototype ‘V’ designation, which can lead to some confusion.
Future Improvements and Modifications
Even as the first series of Bv 222 were under construction, there was a proposal for a new improved civilian version named Bv 222 B, which was to be powered by Jumo 208 engines. Due to the war, this was never implemented and remained a paper project.
As the first series of Bv 222 had some issues with the engines, there were attempts to equip them with better models. For this reason, Bv 222 V7 (reg. TB+QL ) was instead powered by Jumo 207 C 680 hp diesel engines. The idea behind using diesel engines was that the Bv 222 could be refueled at sea by using U-boats. The Jumo 207C engines also proved to have some issues, but it was nevertheless decided to use the Bv 222 V7 as the basis for the C-series. Bv 222 V7 was flight tested in April 1943, and it would remain in service up to the war’s end, when it was destroyed by its crew to avoid capture by Allied forces in May 1945.
Due to the bad wartime situation for the Germans and the lack of materials, only a limited number of C-series aircraft were ever built. Of the nine that were under construction, only about five (beside V7) were ever completed. Two of the C-series aircraft were to be used for a new D-series powered by the Jumo 207 D engines. Due to problems with this engine, production was never implemented.
Bv 222 V2 that was captured by the Allies in Trondheim Fjord. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
The first aircraft of the C-series (Bv 222 C-9) was allocated to Fliegerführer Atlantik on the west in late July 1943. After the Allied landings in France, the Germans lost their air bases in this area. For this reason, the long-range patrol missions were carried out from occupied Norway. C-9 was lost in early 1945 (or 1944, depending on the source), when it was shot down by a British Hawker Typhoon. C-10 was lost in a crash in February 1944. C-11 was fully equipped but was never used operationally for unknown reasons. C-12 was tested with rocket assisted engines to help during takeoff. The use of the C-13 aircraft is unfortunately unclear. While the C-14 to C-17 were under construction, they were never completed due to a lack of resources.
While the Bv 222 was primarily designed as a flying boat, there were plans to modify it to be used as a standard transport plane. This was to be achieved by adding landing gear wheels to it. The projects received the P.187 designation. Possibly due to a low priority, this project was under development up to the war’s end and was never implemented.
Flight to Japan
During the war, the Germans had plans to establish a flight line connection with Japan. Original flight plans stated that the starting point for the Germans was Kirkenes and then to Tokyo via the Sakhalin Island. The Bv 222 was in the competition for this mission, but was rejected due to the small number built and because it was not designed for this role. Other aircraft considered were the Ju 290 and the He 177. The aircraft ultimately chosen was the Ju 290, but this planned flight was never attempted and the whole project was dropped.
The side view of the Bv 222. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
Arctic Rescue Mission
During the war, the Germans managed to set up a secret meteorological station in the Arctic. In the spring of 1944, the crew of this station were sick because they had eaten raw meat. A supply mission was conducted using a Fw 200 for transporting a doctor to this base. The pilot tried to land but, during the landing, one wheel of the landing gear broke down. The base sent back a distress call for further aid. For this mission, one of the Bv 222s was chosen and was loaded with a spare wheel and spare parts. Once it was above the base, the parts were successfully dropped by a parachute. The station crew were eventually rescued once the Fw 200 was repaired.
In Allied Hands
By the end of the war, the Americans managed to capture two Bv 222 aircraft, C-11 and C-13. C-11 would be flown to America and was used for evaluation. While it would eventually be scrapped, it gave the Americans valuable information about designing and building such huge flying bots. C-13 was also flown to America, where it would later be scrapped.
One of the captured Bv 222s used by the British. Source: http://www.warbirdphotographs.com/luftwaffephotos/index.html
The British also managed to capture Bv 222 C-12 in Norway. During the flight to the UK, one of the engines stopped working, but the pilot managed to reach the UK. The British also captured the Bv 222 V2 prototype which was also relocated to the UK. These would serve the British in gaining valuable information about the aircraft’s construction.
Production
The only producer of these aircraft was Blohm & Voss at Hamburg. Due to many factors, such as long development and testing time, the substantial resources needed to build them and the pressing need for fighter aircraft, there was only a limited production run. In total, only 13 Bv 222 were ever made. These included three prototypes, four of the A-series and six C-series aircraft. While there were a few more under construction, these were never completed.
Versions
Bv 222 V1-V3 – Several prototypes built with different armament and engines tested
Bv 222 A – Four aircraft built
Bv 222 B – Proposed improved civilian version
Bv 222 C – Version powered by the Jumo 207 engine, few built
Bv 222 D – Proposed improved C-series to be powered by Jumo 207 D engine, none built
P.187 – Proposed land-based version, none built
Operators
Lufthansa – Although the original purchaser of this aircraft, only V1 saw limited evaluation and testing service in Lufthansa service
Nazi Germany – Operated a small number of these aircraft
USA – Captured two aircraft of the C-series which were used for testing
UK – Captured two aircraft.
Surviving aircraft
Unfortunately, due to wartime attrition and sabotage by their own crews, not a single BV 222 is known to have survived to this day. There are possibly several wrecks underwater, like the one in Greece, that could maybe one day be salvaged or even restored.
Conclusion
The Bv 222 was the largest operational aircraft built during the war. While it was never used in its original role, it would see extensive service with the Luftwaffe, despite being available only in small numbers. Due to its large transport capabilities, it was vital to the Germans, as they lacked transport planes throughout the war. But, due to the bad military situation in the second half of the war and the need for a large number of fighter planes, the Bv 222 would only be built in limited numbers.
Nazi Germany (1938)
Multi-role Fighter – 12 ~ 18 Built
Rear Quarter Drawing of the 240 [Luftnachrichtenhelferin]The Ar 240 was designed as a possible replacement of the Me 110. While initially it seemed to have great potential, problems with handling and mechanical breakdowns proved to be too much for this aircraft. As it would not be accepted for service, only a small number were actually built. While a few were used by the Luftwaffe, their operational usage was limited.
History of Arado
Werft Warnemünde, later known as Arado, was an aircraft manufacturer that was founded during the Great War, in 1917, as a subsidiary of Flugzeugbau Friedrichshafen. In 1921, this company was purchased by an engineer, Heinrich Lübbe, who was more interested in designing and building ships. In 1924, it was once again engaged in development of aircraft designs, mainly intended for foreign markets. For the position of chief designer, Walter Rethel, who previously had worked for Fokker was chosen.
Werft Warnemünde would be renamed in 1925 to Arado Handelsgesellschaft and renamed again in March 1933 to Arado Flugzeugwerke GmbH. At this time, Walter Blume was appointed as the new chief designer. During his supervision, several projects that were later used by the Luftwaffe were built, including the Ar 66 trainer and the Ar 65 and Ar 68 fighter aircraft.
At the start of the Second World War, Arado was mostly engaged in licenced aircraft production for the Luftwaffe. But work on its own aircraft designs was not discarded. The most important of these upcoming designs were the Ar 96 trainer, Ar 196 reconnaissance plane and the Ar 234, which would become the first operational jet bomber in the world. While these proved a huge contribution to the German war efforts, the Ar 240 design proved to be a failure.
Development of the Ar 240
During 1938, the German Ministry of Aviation (Reichsluftfahrtministerium, RLM) was interested in the development of a new multi-purpose twin engine aircraft that would replace the Me 110. Besides Messerschmitt, which began development of the Me-210, the Arado company would also be involved. In early April 1939 or 1938, depending on the source, the Arado company received a contract for the construction of three prototypes of the new multi-purpose plane initially called E-240. The development of this new aircraft was carried out by an Arado team of designers and engineers led by Walther Blume and by Dipl.-Ing. Wilhelm van Nes.
Interestly, possibly for reasons such as good connections with the Nazi Party or Arado’s good reputation as an aircraft manufacturer, even before the completion of the first prototype, an order for 10 additional prototypes was given by the RLM. While these would be built, a number of problems were identified which would prove to be the downfall of the aircraft.
Technical Characteristics
Front view of the Arado Ar 240 V3 prototype. [Luftwaffe Resource Center]Close up of the extended flap system [Luftnachrichtenhelferin]The Arado 240 was designed as a two seater, twin-engined, mid wing monoplane. The fuselage had a monocoque design and stressed-skin. The fuselage was oval-shaped, with the rear part being more round shaped. The rear tail of the Ar 240 consisted of two fins and rudders, but also had dive brakes installed.
The central parts of the wings were rectangular, while the outer part was trapezoidal in shape. The wings were constructed using a two-part spar structure. The Ar 240 used Fowler type flaps, which covered the entire trailing edge. What is interesting is that the Ar 240 flaps were integrated with the ailerons and that this configuration was previously tested on the Ar 198. Another innovation was the use of automatic leading edge slats, but this system was used only on the first few prototypes and abandoned later on. The wings also housed four fuel tanks on each side, which had a total fuel load of 2,300 liters (600 US gallons). The fuel tanks were built using a new self-sealing system that used thinner tank liners, which enabled the aircraft to have a much increased fuel load.
Ar 240 front view. This picture was taken during March 1944. [WarBirds Photos]The Ar 240’s cockpit interior. [WarBirds Photos]The cockpit was initially positioned directly over the place where the wing root. After the third prototype, the cockpit was moved forward. The cockpit used a back to back seat configuration, with the pilot positioned on the front seat and the radio operator, who was also acting as the rear gunner, being positioned in the rear seat. The Ar 240 cockpit was completely pressurized. The cockpit was directly connected to the fuselage, but was provided with a jettisonable canopy in case of emergency. The well designed glazed canopy provided the pilot and crewman with an excellent all-around view.
The Ar 240 used a conventional retractable landing gear which consisted of two front wheels and one smaller tail wheel. The two front wheels retracted outward into the engine nacelles, while the third wheel retracted into the rear tail fuselage section.
The Ar 240 was tested with a number of different engine types, as the designer had problems in finding an adequate one. The prototype series was powered by Daimler Benz DB 601A and DB 603 A. The later built A series would also be tested with a number of different engines, including the DB 601 A-1 and DB 603, BMW 801 TJ etc..
Different armaments were proposed for the AR 240, including a pair of remotely controlled defence turrets. The control of these turrets was hydraulic and they were equipped with periscope aiming sights. The bomb load would consist of around 1 to 1.8 tons, placed under the fuselage.
Development and Usage of the Ar 240 Prototype Series
Another view of the V3 prototype. [WarBirds Photos]Note: Due to differing information depending on the author, the following information was mostly taken from G. Lang. (1996), Arado Ar 240, A Schiffer Military History Book.
The first operational Ar 240 V1 prototype (markings DD+QL), powered by two 1,157 hp DB 601 engines, was completed in early 1940 and was flight tested on the 10th of May the same year. The next flight tests were made on 25th June and 17th July 1940. In May 1941, the engines were replaced with two DB 603 E. More tests were carried out until October 1941, when the prototype was removed from service for unknown reasons. According to M. Griehl, it was destroyed on the 18th April 1941. The test results of the Ar 240 V1 showed that this aircraft had huge problems with the controls and was difficult to fly, a trend which will be inherited on all Ar 240 planes.
The second prototype, V2, is somewhat shrouded in mystery, as the date of its first operational test flight is unknown. A possible date for the first test flight is 15th September 1940. While it is not clear, the V2 prototype probably received the DD+CE markings. Arado test pilots made several flight trials during September 1940. By the end of February 1941, the Ar 240 V2 prototype was relocated to Rechlin for future tests. By May 1941, the V2 prototype received new DB 603 engines. At the same time, it was also fitted with two 7.92 mm (0.311 in) MG 17 and two 20 mm (0.78 in) MG 151/20 cannons. In November 1941, this plane was modified to be used in dive bombing trials. An additional change was the installation of two DB 601 E engines. The final fate of the V2 prototype is not known precisely, but it was probably scrapped.
The Ar 240 V3 (KK+CD) prototype was first flight tested on 9th May 1941. In comparison to the earlier two prototypes, this model had the cockpit moved forward. The rear tail-positioned dive brakes were replaced with a cone and ventral fins. Numerous engines were tested on this aircraft, including two Jumo 203 and DB 601 E. In early 1942, a number of pressure cabin tests were conducted on the V3 prototype. This aircraft also served as a test bed for the new FA-9 remote controlled system developed in cooperation between Arado and the DVL (aviation research institute), but proved to be problematic. V3 would be used operationally as a reconnaissance aircraft over England. It was piloted by Oberst Siegfried Knemeyer, and while his plane was unarmed, thanks to its high speed, he managed to avoid any confrontation with British planes. The fate of this aircraft is not known, as (depending on the sources) it could have been lost in either April 1944 or May 1942.
Row of three Ar 240 prototypes. [Luftwaffe Resource Center]The V4 prototype was to be tested as a dive-bomber variant. The first test flight was made on 19th June 1941. It was powered by two 1,750 hp DB 603 A engines. It was modified with added dive brakes and was capable of carrying up to eight 50 kg (110 lb) bombs under the fuselage. Its fuselage was also elongated to 13.05 m (42 ft 9 ¾ inches). Many detailed tests with the V4 were carried out in France and in the Mediterranean. The V4 prototype was lost in August 1941 in an air accident.
The V5 (GL+QA or T5+MH) prototype made its maiden flight test in September 1941. What is interesting is that it was not built by Arado but by AGO Flugzeugwerken from Oschersleben. It was powered by two 1,175 hp DB 601 E engines and was provided with a tail cone. It was armed with two wing root MG 17 machine guns and two same caliber MG 81 machine guns placed into two (one above and under the fuselage) FA-13 type remotely controlled turrets. In late March 1942, this aircraft was given to the Aufklärungsgruppe Oberbefehlshaber der Luftwaffe (reconnaissance unit/group belonging to the Commander in Chief of the Luftwaffe). It was then, possibly in late 1942, allocated to Versuchsstelle für Höhenflüge VfH (research station for high-altitude flight).
Ar 240 with tow ropes attached in the Soviet Union during the winter of 1942/1943 [Luftnachrichtenhelferin]Ar 240 A-01 used around Kharkov in late 1942. [Luftnachrichtenhelferin]The V6 (GL+QA or T5+KH) prototype was also built by AGO, and while most parts were ready during November 1941, the aircraft was only completed in early 1942. It was flight tested in January 1942, but if this was its first test flight is not clear. It was given to the Luftwaffe in early March 1942 and moved to Oranienburg for future tests. It was similar in appearance and equipment with the previous V5 aircraft. While it was used mostly for testing, it saw front line service during the winter of 1942/43 around the Kharkov area. The plane is listed as destroyed but under which circumstances is not known.
The V7 (DM+ZU) prototype made its first test flight in October or December 1942. It was designed to be used as the basis for the Ar 240 B high-altitude reconnaissance aircraft. It was to be provided with a pressurized cockpit and a heating system. V7 was powered by two 1,475 hp DB 605 A engines, which were specially designed to use a methanol-water injection in order to increase the engine overall performance and output. Armament consisted of two wing mounted MG 17s and a rear mounted remotely-controlled turret armed with the MG 151/20, and two 50 kg (110 lb) bombs. Operational range was 1,900 km (1,180 mi) and it a was capable of climbing to 6 km (19,685 ft) in 10 minutes and 6 seconds.
The V8 prototype was a direct copy of the V7 and possibly made its first test flight in December 1942 or March 1943 depending on the sources. The final fate of this and the previous aircraft is not known.
The V9 (BO+RC) prototype was designed as a Zerstörer (heavy fighter) aircraft. It was to be used as a test base for the planned Ar 240 C version. The V9 had redesigned longer wings and fuselage. It was powered by two DB 603 A engines which were also equipped with a methanol-water injection system. The main armament consisted of four forward and two rear MG 151/20. While this version had a great priority and was even considered for acceptance for production. This was never achieved, mostly due to a lack of necessary equipment and parts. The final fate of this aircraft is not clear, as it was possibly never even fully completed, but some sources also mention that it was lost in a landing accident.
The V10 prototype was designed as a night fighter aircraft, powered by two Jumo 213 engines. The first test flight was made in September of 1943, while more tests would be carried out up to late 1944. Arado reused this aircraft for the new improved version called Ar 440.
The V11 prototype was tested as a heavy fighter-bomber and was to be used as the base of the Ar 240 F aircraft. Due to many delays, it was actually never fully completed. It had the heaviest armament, which included a mix of MG 151 and 30 mm (1.18 inch) MK 103 cannons forward mounted, rear mounted MG 151 and 13 mm (0.5 inch) MG 131 and a bomb load of 1,800 kg (3,970 lbs). V12 was a direct copy of V11 and, as these two aircraft were never completed, both were scrapped. V13 was to be used as a test base of the Ar 240 D equipped with two 2,020 hp DB 614 engines, but none were built.
V14 was probably never fully constructed. It was to be used as a base for the Ar 240 E project and powered by two DB 627 engines. V15 was to be used in a reconnaissance role and equipped with the FuG 202 Lichtenstein radar. The V15 prototype was probably never built.
An Ar 240 during its short operational life in the Soviet Union during the winter of 1942/1943. [WarBirds Photos]There are two more Ar 240 aircraft only known by their serial numbers (240009 and 2400010). While the usage and fate of the first aircraft is generally unknown, the second was used by the Luftwaffe operationally in the Soviet Union during 1943. It was damaged during a landing in August the same year. Its final fate is unknown.
Development of the ‘A’ Version
An Ar 240 during a flight test. [WarBirds Photos]After a series of prototypes were built, work on the first Ar 240 A version was also undertaken by Arado. Initially, the Ar 240 A aircraft were to be powered by two 1.750 hp DB 603 A-1 engines equipped with four blade metal propellers. Armament chosen for this version consisted of two MG 151/20 (with 300 rounds of ammunition for each gun) placed in the fuselage floor and two more MG 151/20 (with same ammunition load) placed in the wings roots. There was an option for increasing the fire power by adding two more MG 151/20. For rear defence, two defense turrets equipped with MG 131 machine guns could be placed under and above the fuselage. The bomb load could have different configurations, like: One 1,000 kg (2,220 lbs) or 1,800 kg (3,930 lbs) bomb, two 500 kg (1,100 lbs) bombs, eight 50 kg (110 lbs) bombs or even 288 smaller 2.5 kg (5 lbs) incendiary and fragmentation bombs. As the Ar 240 was never accepted for service, only few of the A version aircraft were ever built.
Ar 240 A-01 (GL+QA possible marking) made its first test flight on 28th June 1942. The test flights were carried out until September 1942, when this aircraft was to be given to the Luftwaffe. After a series of further flight and weapon tests conducted at Rechlin and Tarnewitz, the Ar 240 A-01 was to be allocated to the front. It was used around Kharkov in late 1942. On 16th February 1943, Ar 240 A-01 was lost during a flight due to mechanical failure. Both crew members lost their lives during the fall.
The second Ar 240, A-02 (GL+QB), was completed by September 1942. On 13th September, the first test flight was made. The aircraft was damaged in a landing accident in late January 1943. The final fate of this aircraft is not known.
Many Ar 240 were lost in crash landings.[Luftnachrichtenhelferin]Ar 240 A-03 (DI+CY) was initially powered by two DB 601 engines, but these were replaced with BMW 801 TJ. This aircraft had a change in the cockpit configuration, with the radio operator/observer facing forward. This aircraft was stationed at Rechlin, where it was tested from May to June 1943. During testing, Ar 240 A-03 showed to have better stability and handling during flight in contrast to previous built aircrafts. From June to late July, it was tested at Brandenburg. After these tests were completed, the aircraft was allocated for operational front use. It was given to the Aufklärungsgruppe 122, a reconnaissance unit stationed in Italy at that time. This aircraft had the same fate as most previous Ar 240, as it was heavily damaged in a crash. As the damage was extensive, it was never repaired.
Ar 240 A-04 (DI+CG) was initially equipped with two DB 601 E engines, but these would be later replaced with DB 603. It made its first flight test in late September 1942. Ar 240 A-04 was allocated to the Aufklärungsgruppe 122 as a replacement for the previous aircraft. Ironically, it suffered the same fate, but it was repaired and sent back to Arado.
Ar 240 A-05 was powered by two 1880 hp BMW 801 TJ engines equipped with a Rateau type turbo supercharger. It was possibly allocated to Aufklärungsgruppe 10 stationed in the Soviet Union.
Proposed Versions
During the Ar 240’s development, the Arado officials proposed several different variants of this aircraft, but as the whole project was not going well beside a few experimental attempts, nothing came from most of them.
Ar 240 B
This was a high-altitude reconnaissance aircraft version that was to be equipped with a pressurized cockpit and a heating system. Nothing came from this project.
Ar 240 C
On 10th March 1942, Arado officials proposed that the Ar 240 should be modified for the bomber role. For this reason, the wings were modified and its size increased. The tail design was also changed, with added tail dive brakes. As the attempt to increase the size of the internal fuel tanks proved a failure, external tanks were to be used instead. The armament consisted of two MG 151/20 and two rear mounted MG 81. It is not clear, but it is possible that at least one aircraft was built.
Ar 240 D
A proposed paper project version powered by two DB 614 engines.
Ar 240 E
A proposed version with reinforced fuselage, added bomb rack for two 500 kg (1,100 lbs) bombs and increased fuel load. Different engines were also proposed for this version, including DB 603 G, DB 627 or BMW 801 J.
Ar 240 F
A proposed heavy fighter/bomber version to be powered by two DB 603 G engines.
Ar 240 mit 7.5 cm Bordwaffen
During the war, Arado and Rheinmetall discussed the installation of a 7.5 cm gun in the Ar 240. In September 1944, it appears that one plane was actually equipped with this weapon, but was probably never operationally flight tested.
Ar 240 TL
In 1942, Dr. Ing. Walther Blume proposed a heavy fighter and night-fighter version of the Ar 240. This version was designated as Ar 240 TL, which stands for Turbinen-Luftstrahltriebwerk (turbojet). This plane was to be powered by two jet engines placed in the fuselage. It remained only a paper project.
Ar 440
With the cancellation of the Ar 240 project, Arado tried to improve the Ar 240’s overall performance by building a new version, named Ar 440. The Ar 240 V10 prototype served as a base for this modification. Beside this prototype, three more were built using already existing Ar 240 components. After some time in testing, the Ar 440 was officially rejected in October 1943 by the RLM.
Overall Performance and Cancellation of the Ar 240 Project
The Ar 240 possessed several advanced characteristics like a pressurized cockpit, remote-controlled defensive turrets, traveling flaps which provided this aircraft with good low-speed overall lift performance and fuel tanks with a new self-sealing system that used thinner tank liners. But, almost from the start of first flight testing, things turned from bad to worse for this aircraft. Almost from the start, the Ar 240 was plagued with extremely bad handling on all three axes. There were also huge problems with the controls during landing, with most aircraft being lost due to this. As the aircraft proved to be dangerous to fly, it was never adopted and the initial orders for production of 40 aircraft were never materialized.
Allied Examination After the War
Strangely, despite being a rare aircraft, the Allies managed to capture at least one Ar 240 during their advance in the West in 1944/45. This aircraft was tested by Allied pilot Captain Eric Brown. He was Chief test pilot of the Royal Aircraft Establishment at Farnborough. He was involved in a British project of taking over of German war research installations and interrogating technical personnel after the war. After the war, he managed to find the single surviving Ar 240 and, after a flight on it, made a report on its performance. The source for this account is Wings Of The Luftwaffe Flying The Captured German Aircraft of World War II by Eric Brown. This aircraft would be given by the Allies to the French and its fate is unknown.
In his report, he stated. “When the Ar 240 was wheeled out of the hangar, I was struck by its angular appearance. The wings, fuselage, and tail unit all seemed to be straight-edged, with very few curves to be seen. The engines looked very large, the airscrew spinners being level with the nose of the cockpit and well ahead of the wing leading edge, while the nacelles protruded well aft of the trailing edge. I had the feeling that, if this aeroplane was as fast as it was reputed to be, then brute engine force must be the answer … The cockpit layout was neat and the instruments were quite logically arranged, while the view was good all around except downwards on either side, where the engines interfered. Take-off was quite long, even with using 20 degrees of flap, and the initial climb rate was just over 600 m/min (2,000 ft/min). Longitudinal stability was poor, lateral stability neutral, and directional stability positive. The rate of climb fell off very little as I climbed to 6,096 m (20,000 ft), where I levelled out and settled into the cruise at what I calculated was a true airspeed of 580 km/h (360 mph). In the cruise, the aeroplane could not be flown hands-off because it diverged quickly both longitudinally and laterally, and would be tiring to fly for a long time. An autopilot was fitted, although not serviceable in my case, but I believe it would have been essential for instrument flying in bad weather. On opening up to full power, I estimated that after three minutes I was hitting an impressive true airspeed of 628 km/h (390 mph), but it was obvious that the Ar 240 was a poor weapons platform. The harmony of control was terrible, with heavy ailerons, light elevators. and moderately light rudders. ….
My assessment of the Arado Ar 240 is that it was an aircraft of outstanding performance for its class and era, but it could not capitalise on this because of inferior, and indeed dangerous, handling characteristics. According to German information, it had a service ceiling of 10,500 m (34,450 ft) and a maximum range of 1,186 miles, so it had great potential as a reconnaissance intruder, and indeed it is claimed that it made such sorties over Great Britain in 1941 and 1944. Be that as it may, there can be little doubt that the Ar 240 was a failure ..”
Production Numbers
While the Ar 240 production was initially to begin in 1941, due to many problems and delays, this was not possible. While there were attempts to start production, by the end of 1942, the RLM officially terminated the program.
How many aircraft were built depends on the source. According to author G. Lang, the problem with identification of the production numbers is complicated by the fact that some prototype aircraft were allegedly modified and used for the few A-series aircraft built. Another issue, according to Lang, is that the highest known serial number production was 240018 (starting from 240000), which suggests that at least 18 were built, but it is not completely clear. Authors Ferenc A. and P. Dancey mention that at least 15 were built by 1944. Eric Brown claims that 12 prototypes were built.
Main Production and Prototypes
Ar 240 V1-V14 – Prototypes series used to test different equipment, armament and engines.
Ar 240 A – Was to be main production version, but only few aircraft were actually built
Ar 240 B – High-altitude reconnaissance version, possibly few built.
Ar 240 C – A bomber version, unknown if any were built.
Ar 240 D – Proposed version powered by two DB 614 engines.
Ar 240 E – Proposed modified Ar 240 version.
Ar 240 F – Proposed heavy fighter/bomber version to be powered by two DB 603 G engines.
Ar 440 – An improved version of the Ar 240. Only a few were built. The project was cancelled in 1943.
Ar 240 mit 7.5 cm Bordwaffen – A proposed version armed with a 7.5 cm gun, possibly one built, but its fate is unknown.
Ar 240TL – A jet-powered paper project.
Operators
Germany – Operated small numbers of these aircraft, mostly for testing and reconnaissance operations.
France – Captured one, but the fate is not known.
Conclusion
While the Ar 240 was, on paper, an excellent design with many innovations and advanced technology, in reality it did not live up to expectations. The plane proved to be dangerous during flight and many were damaged during landing, with fatal outcomes. Because the Ar 240 proved to be difficult to control, the RLM simply decided to stop the project, as it was probably unwilling to waste more time and resources on it.
Arado Ar 240 A-0 Specifications
Wingspan
14.3 m (47 ft)
Length
12.8 m (42 ft)
Height
3.95 m (13 ft)
Wing Area
31 m² (333 ft²)
Engine
Two liquid cooled twelve-cylinder 1,750 hp DB 603 A-1
Empty Weight
6,350 kg (14.000 lbs)
Maximum Takeoff Weight
10,500 kg (23,150 lbs)
Fuel Capacity
2,300 liters (607.6 US gallons)
Maximum Speed at 6 km
670 km/h (415 mph)
Cruising Speed
600 km/h (370 mph)
Range
2,200 km (1,370 mi)
Maximum Service Ceiling
11,500 m (37,730 ft)
Climb speed
Climb to 6,000 m in 9.7 minutes
Crew
Two pilot and the rear radio operator/gunner
Armament
Four 2 0mm (0.78 inch) MG 151/20
Two 13 mm (0.5 inch) MG 131
One 1,000 kg (2,220 lbs) or one 1,800 kg (3,930 lbs) bomb
Or two 500 kg (1,000 lbs) bombs,
Or eight 50 kg (110 lbs) bombs,
Or 288 2.5 kg (5 lbs) incendiary and fragmentation bombs
Nazi Germany (1942)
Transport Floatplane – 1 Built
BV238 on the Water [Colorization by Michael Jucan]With the success of the previous Blohm & Voss Bv 222 flying boat, Dr. Ing. Richard Vogt, chief designer at Blohm & Voss, began working on an even larger improved design in the form of the Blohm & Voss Bv 238. As the Bv 238 development began in the late stages of the war, only one aircraft was ever completed and used only briefly.
Dr. Ing. Richard Vogt’s Work
In 1937, Lufthansa opened a tender for a long-range passenger flying boat transport that would be able to reach New York in 20 hours. Blohm & Voss eventually would go on to win this tender. The chosen aircraft was the Blohm & Voss Bv 222, designed by Dr. Ing. Richard Vogt.
During 1941, Dr. Ing. Richard Vogt began working on a new aircraft larger even than the already huge Blohm & Voss Bv 222. In July the same year, he presented to the RLM, the German ministry of aviation (Reichsluftfahrtministerium), the plans for the new Blohm & Voss Bv 238. This aircraft was, in essence, a modified and enlarged version of the Bv 222 powered by six Daimler-Benz DB 603 engines. Three aircraft powered with this engine were to be built, belonging to the A-series. Six more aircraft were to be powered by six BMW 801 engines and these would be designated as B-series.
To speed up the development and avoid wasting resources if the project proved to be unsuccessful, the RLM officials asked for a smaller scale flying model to be built first instead of a working prototype. This scale model plane was named FG 227 (or FGP 227, depending on the source) and was to be built and tested at Flugtechnische Fertigungsgemeinschaft GmbH located in Prague.
The FG 227 scale flying model
To speed up the development and avoid wasting resources, the RLM officials asked for a smaller scale flying model to be built first. How it turned out the FG 227’s overall performance was disappointing and it didn’t play any major role in the Bv 238 development. [Histaviation]The construction of this scale model was undertaken by a group of Czech students under the direction of well-known glider pilot Dipl.Ing. Ludwig Karch. It was to be powered by six ILO Fl 2/400 engines pushing 21 hp each. As it was meant to be tested on the ground and not in water, the FG 227 was provided with landing gear which consisted of two wheels in the nose and two more wheels placed on each side of the fuselage.
The small scale model, designated the FG 227 [Histaviation]When the FG 227 was completed, it was to be flight tested. From the start, there were issues with it, as it was unable to takeoff under its own power. After the unsuccessful start, it was disassembled and transported to Travemünde for future testing. During transport, French prisoners of war deliberately damaged one of the wings. Once the damage was repaired, it was flight tested. But during the flight, made in September 1944, all six engines stopped working, which caused an accident where the FG 227 was damaged. After yet another major repair, a few more flights were carried out. The FG 227’s overall performance was disappointing and it didn’t play any major role in the Bv 238 development.
The FG 227’s small scale engines being serviced [Histaviation]The Bv 238
Rear view of the Bv 238 [Warbird Photographs]Construction of the first Bv 238 parts began in early 1942. The final assembly was not possible until January 1944. Due to a shortage of materials and the increasing assaults by the Allied Air Forces, the Bv 238 V1 first prototype could not be completed until March of 1945. The first flight test we conducted immediately after its completion. However, sources do not agree on the exact year when this happened. This is the timeline of development and construction according to author H. J. Nowarra.
Author M. Griehl states that the first flight test was made on the 11th of March 1944. Author C. R. G. Bain states, according to post war testimonies of Dr. Ing. Richard Vogt, that the first test flight was actually made in 1943. According to D. Nešić, the first flight was made in April 1944. The results of this test flight showed that the Bv 238 prototype had surprisingly excellent flying performance. For this reason, it was immediately put into operational service.
Front view of the Bv 238 with the nose hatch doors open [Warbird Photographs]Throughout the Bv 238 development phase, it was often discussed precisely which role it could fulfill. While it was primarily designed as a transport plane, a new idea was proposed to act as a U-boat support aircraft. This would include carrying supplies, fuel, torpedos and men to the U-boats operating in the Atlantic. Of course, by the time the first prototype was near completion, the war was almost over, so this proposal was realistically not possible. Plans to use it as a long range bomber, carrying six 2,400 kg bombs, also never materialized.
Bv 238 V1 was meant to operate from Shaalsee, and for its service with the Luftwaffe, it received the RO+EZ designation. As the Allied bombing raids effectively destroyed the Blohm & Voss factory in Hamburg, orders came down to hide the Bv 238 from the Allied Air Force. The question was how to hide such a huge aircraft. The Germans did try to do so but the aircraft was eventually found by the Allies who managed to sink it. The circumstances are not clear to this day, as both Americans and the British pilots claimed the kill. According to the most well-known story, it was destroyed by a group of American P-51 Mustangs belonging to the 131st Fighter Group. The kill was made by the leading P-51 piloted by Lt. Urban Drew. According to the testimony of the Blohm & Voss workers, the British, in their advance discovered the hidden craft. Once spotted, the British sent attack aircraft to sink it. Its remains would finally be blown up during 1947 or 1948 to make the scrapping process easier. All the remaining Bv 238 that were under construction were also scrapped after the war.
Technical Characteristics
The Bv 238 was designed as a six-engined, high wing, flying transport floatplane. The Bv 238 fuselage was divided into two decks. On the upper deck, the crew and the inboard equipment were housed. The lower floor was designed as a storage area during transport flights. In theory, there was enough room for around 150 soldiers in the Bv 238. A huge front hatch door was provided for easy access to the fuselage interior.
The wings were constructed using large tubular main spars. The wings were used to provide additional room for spare fuel and oil tanks. The wings were provided with flaps running along the trailing edge. The large size of the wing construction allowed passageways for the crew to be installed, in order to have easy access to the engines. Unlike the Bv 222, which had a pair of outboard stabilizing floats mounted on each side, the Bv 238 had only two. The Bv 238 was powered by six Daimler DB 603G engines.
For self defense, the Bv 238 was to be provided with two HD 151 twin-gun turrets with 20 mm (0.78 in) MG 151 cannons, two HL 131 V turrets with four 13 mm (0.51 in) MG 131 machine-guns and two additional MG 131s mounted in the fuselage sides. Despite the plans to arm the V1 prototype, this was never done.
The crew number is mentioned as 11 or 12 depending on the source. The sources do not specify the role they performed. It can be assumed, based on what is known from Bv 222, that there were at least two pilots, two mechanics, a radio operator and machine gun operator.
Production
Despite being based on the large Bv 222, the Bv 238 was even larger [Warbird Photographs]The production of the Bv 238 was carried out by Blohm & Voss factory at Hamburg. Only one completed prototype would be built during the war. There were also at least two to six more prototypes under construction (depending on the source), but due to the war ending, none were completed.
The small number under construction may be explained by the fact that, in the late stages of the war, the Luftwaffe was more in need of fighter planes than transports planes. In addition, there is a possibility that the Bv 238 project was actually canceled by the RLM officials.
Versions
Bv 238 A – Powered by Daimler-Benz DB 603 engines, only one built
Bv 238 B – Powered by six MW 801 engines, none built
Bv 250 – Land based version, none built
FG 227 – Scale test model of the Bv 238, used for testing
Land Based Version
There were plans to adapt the Bv 238 for land based operations by adding landing gear wheels. The project was designated Bv 250 but none were ever built. It was planned to provide this version with heavy defence armament consisting of twelve 20 mm (0.78 in) MG 151 cannons. The engine chosen for this model was the six Jumo 222. As this engine was never built in any large numbers, the DB 603 was meant to be used instead.
Escape Aircraft
There are some rumors that the Bv 238 was actually developed as an escape aircraft for high ranking Nazi officials. It was rumored that Martin Bormann had plans to use it to escape Germany in early 1945. Of course, due to Allied Air Force supremacy and the Bv 238’s large size, this may have not been a viable plan if ever attempted.
Conclusion
The V1 Prototype after its maiden test flight [Warbird Photographs]If it was put into production, the Bv 238 would have had the honor of being the largest flying boat that saw service during the war. While it only performed test flights and was never used operationally, it was nevertheless an astonishing engineering achievement.
Blohm & Voss BV 238 V1 Specifications
Wingspan
196 ft / 60 m
Length
145 ft / 43.4 m
Height
35 ft 9 in / 10.9 m
Wing Area
3,875 ft² / 360 m²
Engine
Six 2900 hp Daimler-Benz DB 603
Empty Weight
120,500 lb / 54,660 kg
Maximum Takeoff Weight
207,990 lb / 94,340 kg
Maximum Speed
220 mph / 355 km/h
Cruising Speed
210 mph / 335 km/h
Range
3,790 mi / 6,100 km
Maximum Service Ceiling
20,670 ft / 6,300 m
Crew
11-12 (2 pilots, 9 airmen)
Armament
none
Gallery
The sole completed Bv238V1 Prototype by Ed Jackson
The Fi 167 was developed out of a need for a dedicated torpedo-bomber to be operated on the first German aircraft carrier. While its overall performance proved to be satisfactory, due to the cancellation of the aircraft carrier project, only a small number were ever built. Unfortunately, information about the Fi 167 is not available or precise enough, with many disagreements between different authors.
Fieseler Flugzeugbau
In the early 1930’s, World War I fighter veteran Gerhard Fieseler (1896–1987) bought the Segelflugzeugbau Kassel Company, which mostly produced gliders, and renamed it to Fieseler Flugzeugbau. Gerhard Fieseler had gained experience in aircraft design while working as a flight instructor for the Raab-Katzenstein Aircraft Company in Kassel. In 1926, he managed to design his first aircraft, named Fieseler F1, which would be built by the Raab-Katzenstein company. By the end of twenties, Gerhard Fieseler designed another aircraft, the Raab-Katzenstein RK-26 Tigerschwalbe, of which 25 were built and sold to Swedish Air Force.
With his own company, he changed to focus on sports aircraft. In 1935, Gerhard Fieseler managed to obtain a licence for the production of military aircraft. While his best known design was the Fi 156 ‘Storch,’ he also designed the less known Fi 167 torpedo-bomber. The Fi 167 was built in small numbers and never managed to reach the fame of the Storch.
History of the Fi 167
Engine view of the Fi 167. [Valka.cz]As the German Navy began construction of its first aircraft carrier, the ‘Graf Zeppelin,’ in 1937, there was a need for a completely new torpedo bomber. For this reason, the German Ministry of Aviation (Reichsluftfahrtministerium) opened a tender for all German aircraft manufacturers who wished to participate to present their designs for such aircraft. The new aircraft was requested to have folding biplane wings, the best possible STOL (short take-off and landing) capabilities, and that the whole construction should have sufficient strength to successfully endure offensive combat operations at high speeds.
Only two manufacturers, Fieseler and Arado, presented their designs. For Fieseler it was the Fi 167 and for Arado the design was the Ar 195. In the summer of 1938, after a series of flight tests, the Fieseler Fi 167 was declared the better design. For this reason, another prototype was to be built for further testing.
The first prototype built, Fi 167 V1 (serial no. 2501), was powered by a DB 601 A/B engine. It was used mainly for testing and evaluation purposes. The second prototype (serial no. 2502) had some changes to the design, such as a modified undercarriage and was powered by the DB 601B. This engine would be used on later production versions. While most sources state that only two prototypes were built, some authors, like M. Griehl (X-Planes German Luftwaffe Prototypes 1930-1945), mention a third prototype being built. This third prototype, Fi 167 V3 (serial no. 2503), according to Griehl, was used to test the equipment used on this plane. While the sources do not give precise details about the fate of the Fi 167 prototypes, after May 1940, they were not present in the Luftwaffe inventory anymore. This may indicate that all three were scraped. After a number of tests with the Fi 167 were completed, series production of 80 aircraft was ordered.
Short lived operational service life
Fi 167 during flight in German service [Nature & Tech]Despite having promising overall performance, the Fi 167 was directly connected with the Graf Zeppelin project. While the production of a small series was underway, the construction of the Graf Zeppelin aircraft carrier was stopped in 1940, so the same fate befell the Fi 167, as there was no longer a need for a carrier capable fighter. In 1942, there was a brief revival of the aircraft carrier concept, but by that time the Ju 87C was deemed better suited for this role. This decision was not without merit, as the Ju 87 was already in production and it would be much easier, quicker, and cheaper to simply modify it for the role of aircraft carrier torpedo bomber than to put the Fi 167 back into production.
As a small number of 12 Fi 167 A-0 were built, they were sent to Holland for evaluation and testing purposes in order not to waste the resources invested in them. These were used to form Erprobungstaffel 167 which operated in Holland from 1940 to 1942. In 1943, the Fi 167 were returned to Germany and Erprobungstaffel 167 was disbanded. Their use by the Germans from 1943 onward is not completely clear in the sources. While the majority were given to Germany’s allies in late 1944, the final fate of the remaining aircraft is not known, but they were probably either lost or scrapped.
Technical characteristics
Designed to operate from an aircraft carrier, the folding wings were necessary [Nature & Tech]The Fi 167 was an all-metal, single engine biplane designed as a torpedo bomber. The Fi 167’s fuselage was constructed by using thin but with high-strength steel tubes that were welded together and then covered with duralumin sheet metal.
In the glazed cockpit there was room for two crew members, the pilot and the observer/rear gunner. The cockpit was covered with plexiglass but was open to the rear in order to provide the rear gunner with a good arc of fire. The Fi 167 was powered by the Daimler-Benz DB 601B 12-cylinder inverted-V engine putting out 1,100 horsepower. The total fuel load was 1,300 liters.
The Fieseler Fi 167 had a biplane layout. The upper and lower wings were the same in size and had a rectangular shape with rounded edges. The wings were divided into three parts in order to make any necessary maintenance or disassembly easier. Being designed to be used on an aircraft carrier, the Fi 167’s wings could also be folded. In order to be adequately structurally stable, the upper and the lower wings were interconnected by ‘N’ shaped metal rods. There were four of these ‘N’ shaped metal rods in total. These were then held in place with steel cables. For better control during flight, both wings were provided with flaps.
The landing gear consisted of two independent fixed landing wheels which were provided with shock absorbers to ease the landing. The forward landing gear units were covered with duralumin coating to help reduce the aerodynamic drag. To the rear there was a smaller fixed landing wheel. The Fi 167 landing gear was designed to be easily discarded in the case of a forced landing on water. The idea was that it would enable the Fi 167 to float on the water surface and thus provide more time for the crew to successfully evacuate the aircraft.
The armament consisted of two machine guns, one forward mounted 7.92 mm MG 17 with 500 rounds of ammunition and a second MG 15 of the same caliber mounted in a rear, flexible mount with 600 rounds of ammunition. The Fi 167 could be additionally armed with up to 2,200 lbs (1,000 kg) of bombs or one torpedo. In some sources, it is mentioned that there were actually two forward mounted machine guns.
Production
The German Navy was trying to build its first aircraft carrier, the Graf Zeppelin, but due to various reasons it was never completed. [Vaz]The Fi 167 production run was quite limited, mostly due to cancellation of the Graf Zeppelin aircraft carrier. Besides the two or three prototypes, only a small series of Fi 167 (A-0) pre-production aircraft were made. How many were built varies depending on the source. Authors C. Chant (Pocket Guide: Aircraft Of The WWII) and D. Nešić (Naoružanje Drugog Svetskog Rata Nemačka) mention that, besides two prototypes, 12 pre-production aircraft were built. Authors F. A. Vajda and P. Dancey (German Aircraft Industry And Production 1933-1945) give a number of 15 aircraft produced. They also mention that a serial production of 80 Fi 176 was to be completed by June 1941 but, due to the cancelation of the project, this was never achieved. On different internet websites, the total number of Fi 167 built varies between 14 and 29.
Fi 167 V1 – Powered by the DB 601 A/B engine.
Fi 167 V2 – Had modified undercarriage and was powered by the DB 601B engine.
Fi 167 V3 – Possibly-built third prototype, but sources are not in agreement about its existence.
Fi 167A-0 – 12 aircraft built.
In Romanian hands?
It is commonly stated in many sources that the Fi 167 were sold to Romania in 1943. These were allegedly used to patrol the Black Sea. This is likely incorrect, as another German ally, the Independent State of Croatia ‘NDH,’ received nearly all Fi 167 produced. There is a possibility that the Fi 167 were given to Romanians and then returned back to Germany. But due to the lack of any valid documentation, this is only speculation at best.
In NDH service
Fi 167 (serial no. 4808) in NDH service. This is the aircraft that pilot Romeo Adum deserted to the Partisan side. [Vaz]A group of 11 (or 10 depending on the source) Fi 167 (serial no. 4801-4812) arrived in NDH during September 1944. These aircraft were given to the 1st Squadron stationed in Zagreb for the necessary pilot training. While during its service in the NDH, the Fi 167 was used in bombing combat operations, but was mostly used as a transport plane for food and ammunition. Due to having no problem carrying significant loads and its ability to take off or to land on short airfields, they were ideal for supplying many NDH garrisons besieged by Yugoslav Partisans.
Due to the overall difficult situation of the Axis forces on all fronts, the NDH Army and Air Force were plagued with frequent desertions, including a number of pilots. On 25th September 1944, while flying a Fi 167 (serial no. 4808), pilot Romeo Adum escaped to the Yugoslav Partisan held airfield at Topusko.
There is an interesting story about one Fi 167 piloted by Mate Jurković, as it is claimed he managed to avoid being shot down by five American P-51 Mustangs. This engagement happened on 10th October 1944 during a Fi 167 ammunition supply mission to Bosanska Gradiška. During this flight, the Fi 167 was attacked by a group of five Mustangs. Outgunned and outnumbered, the pilot could only hope to escape by using the Fi 167’s excellent maneuverability at lower altitudes. He eventually managed to escape his pursuers without taking any damage.
Due to a lack of spare parts, Allied air supremacy and Partisan advance, by April 1945 there were only four Fi 167 still present in the NDH Air Force. The condition of these planes is not known. Of these, at least three would be used after the war by the new JNA (Yugoslav People’s Army) army. During its operational use by the NDH Air Force, the Fi 167 was known as ‘The Great Fiesler’.
In Partisan hands
The Fi 167 operated by the Yugoslav Partisans during the war. The Red Star can be seen painted under the lower wings. [paluba.info]As mentioned earlier, the Partisans managed to acquire one Fi 167. It would be redeployed to the island of Vis and included in the group of NDH aircraft that had defected earlier (one FP 2, two Saiman 200s, one Bü 131, and one Fiat G. 50).
On the 17th of October 1944, while on a liaison mission from Vis to the village of Vrdovo, after delivering orders to the command of the Partisan 20th Division stationed there, the Fi 167 piloted by M. Lipovšćak and with General Ćetković as a passenger began taking to the sky. Unfortunately for them, a group of four P-51 Mustangs attacked the lone aircraft. The Fi 167 was hit in the engine and the tail and the wounded pilot was forced to land on a nearby open plateau. While the pilot was only wounded, General Ćetković was dead, being directly hit by machine gun fire. Circumstances of this accident are not clear even to this day. The P-51 pilots later claimed that, due to bad weather, they could not see the Partisan markings. By the later account of the Fi 167 pilot, he claimed that the visibility was such that the Partisan markings could have been easily seen.
In JNA service
At least three Fi 167 were put into use by the JNA (Yugoslav People’s Army) after the war. Due to the lack of spare parts, their use was probably limited. They would remain in use up to 1948, but unfortunately they were probably all scrapped, as none survive to this day.
Conclusion
Despite being considered an overall good design, the Fi 167 was never put into mass production. The main reason for this was the cancellation of the Graf Zeppelin aircraft carrier. Nevertheless, the Fi 167 did see some limited service within the Luftwaffe, mainly for testing, but also with the Croatia NDH, where its performance was deemed sufficient.
Operators
Nazi Germany – Used the small number of Fi 167, mostly for various experimental purposes.
Romania – Allegedly supplied with Fi 167 in 1943, but this is not confirmed.
Independent State of Croatia NDH – Operated 10 to 11 aircraft between September 1944 and April 1945.
SFR Yugoslavia – Operated a small number of Fi 167 during the war and up to 1949.
Specification: Fi 167
Wingspan
44 ft 3 in / 13.5 m
Length
37 ft 5 in / 11.4 m
Height
15 ft 9 in / 4.8 m
Wing Area
490 ft² / 45.5 m²
Engine
One 1100 hp (820 kW) Daimler-Benz DB 601B
Fuel load
1,300 l
Empty Weight
6170 lb / 2,800 kg
Maximum Takeoff Weight
10,690 lb / 4,860 kg
Maximum Speed
200 mph / 325 km/h
Cruising Speed
168 mph / 270 km/h
Range
800 mi / 1,300 km
Maximum Service Ceiling
26,900 ft / 8,200 m
Crew
One pilot and one observer/rear gunner
Armament
One 7.92 mm MG 17 forward-firing machine gun
One 7.92 mm MG 15 rear mounted machine gun
Bomb load of 1.000 kg (2.200 lbs)or 750 kg (1650 lbs) torpedo
Fi 167A-0 in service with Erprobungsstaffel 167 in the Netherlands 1940 – Equipped with a centerline rack and torpedoFi 167A-0 (W.Nr.08) in service with Erprobungsstaffel 167 in the Netherlands 1940 – Seen here sporting a different camo patternFi 167 No. 4806 in Croatian ServiceFi 167 in Partisan Yugoslav service circa 1944Artist Concept of the Fi 167 in Romanian Service in 1943
While the Fi 167 proved to have excellent handling characteristics, due to the cancelation of the German aircraft carrier project, it was not accepted for service. [Vaz]Another view of a flying Fi 167. [Valka.cz]Sources
Germany (1943)
German Empire (1915)
