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North American F-86A Sabre

USA flag old United States of America (1947)
Jet Fighter – 554 Built

F-86A-1-NA Sabre 47-630 in flight (North American Aviation)

The iconic F-86A got its first official production underway with the A series in 1947, with the initial examples fulfilling many testing duties, followed by a larger second production batch for active service. The development of these first Sabres would address many teething problems with the aircraft’s engines, speed brakes, and weaponry.  The A models, alongside many other first generation American jet aircraft would go on to see a few short years of service in the Korean theatre as well as defense of the United States before being eclipsed by the relatively rapid development of more advanced jet designs.

History

The P-86A was the first production version of the Sabre. North American had received an order for 33 production P-86As on November 20, 1946, even before the first XF-86 prototype had flown. The P-86A was outwardly quite similar to the XP-86, with external changes being very slight. About the only noticeable external difference was that the pitot tube was moved from the upper vertical fin to a position inside the air intact duct.

Major Richard L. Johnson, USAF with F-86A-1-NA Sabre 47-611 and others at Muroc AFB, 15 September 1948. (F-86 Sabre, by Maurice Allward)

The first production block consisted of 33 P-86A-1-NAs, ordered on October 16, 1947. These were known as NA-151 on North American company records. Serials were 47-605 through 47-637. Since there were officially no YP-86 service test aircraft, this initial production block effectively served as such.

The first production P-86A-1-NA (serial number 47-605) flew for the first time on May 20, 1948. The first and second production machines were accepted by the USAF on May 28, 1948, although they both remained at Inglewood on bailment to North American for production development work. Aircraft no. 47-605 was not actually sent to an Air Force base until April 29, 1950. It remained at WPAFB until May of 1952, when it was retired to storage at the Griffiss Air Depot.

In June of 1948, the P-86 was redesignated F-86 when the P-for-pursuit category was replaced by F-for-fighter

By March of 1949 the last F-86A-1-NA (47-637) had been delivered. Most of the 33 F-86A-1-NAs built were used for various tests and evaluations, and none actually entered squadron service.

The first production block to enter squadron service was actually the second production batch, 188 of which were ordered on February 23, 1949. They were assigned the designation of F-86A-5-NA by the USAF, but continued to be carried as NA-151 on company records. Serials were 48-129 to 48-316. These were powered by the J47-GE-7 jet engine. Deliveries began in March of 1949 and were completed in September of 1949.

A contract for 333 additional F-86As was received on May 29, 1948, and the final contract was approved on February 23, 1949. These aircraft were assigned a new designation of NA-161 on North American company records, but continued to be designated F-86A-5-NA in USAF records. Their serials were 49-1007 to 49-1229. These were powered by the General Electric J47-GE-13 engine which offered 5200 pounds of static thrust. The cockpit wiring was simplified. New 120-gallon drop tanks, developed specifically for the F-86, were introduced during this production run. Deliveries commenced in October of 1949 and were completed by December of 1950. The 282nd F-86A aircraft had a redesigned wing trailing edge with shorter chord aileron and greater elevator boost. Deliveries commenced October 1949 and ended in December 1950.

First Deployment

The first USAF combat organization to receive the F-86A was the First Fighter Group based at March AFB in California, with the famous “Hat in the Ring” 94th Squadron being the first to take delivery when they traded in their F-80s for the F-86A-5-NA during February of 1949. The 27th and 71st Squadrons were equipped with F-86A-5-NAs next, and by the end of May of 1949 the group had 83 F-86As on strength. This group was charged with the aerial defense of the Los Angeles area, which, coincidentally, is where the North American Aviation factory was located. Next to get the F-86 the the 4th Fighter Group based at Langley AFB, charged with the defense of Washington, D.C, and then the 81st Fighter Group, based at Kirtland AFT and charged with the defense of the nuclear bomb facilities at Alamogordo, New Mexico. Next came the 33rd Fighter Group based at Otis AFB in Massachusetts, charged with defending the northeastern approaches into the USA. In January of 1950, all air defense units were redesignated as Fighter Interceptor Groups (FIGs) or Fighter Interceptor Wings (FIWs) as a part of the Air Defense Command.

Origin of the “Sabre” Name

In February of 1949, there was a contest held by the First Fighter Group to choose a name for their new fighter. The name *Sabre* was selected, and was made official on March 4, 1949.

Reserves

The first Sabres that went to Reserve units were assigned to the 116th Fighter Interceptor Squadron of the Air National Guard, which received its first F-86As on December 22, 1950.

The following Wings were issued with the F-86A:

  • 1st Fighter Interceptor Wing (27th, 75st and 94th Squadrons)
  • 4th Fighter Interceptor Wing (334th, 335th, 336th Squadrons)
  • 33rd Fighter Interceptor Wing (58th, 59th and 60th Squadrons)
  • 56th Fighter Interceptor Wing (61st, 62nd, 63rd Squadrons)
  • 81st Fighter Interceptor Wing (78th, 89st, 92nd Squadron)

The F-86A was replaced in active USAF service by the F-86E beginning in the autumn of 1951. As F-86As left active USAF service, they were refurbished, reconditioned and transferred to Air National Guard units in the United States. The first ANG units to get the F-86A were the 198th Squadron in Puerto Rico, the 115th and 195th Squadrons at Van Nuys, California, the 196th at Ontario, and the 197th at Phoenix, Arizona.

Record Breaker

In the summer of 1948, the world’s air speed record was 650.796 mph, set by the Navy’s Douglas D-558-1 Skystreak research aircraft on August 25, 1947. Like the record-setting Lockheed P-80R before it, the Skystreak was a “one-off” souped-up aircraft specialized for high speed flight. The USAF thought that now would be a good time to show off its new fighter by using a stock, fully-equipped production model of the F-86A to break the world’s air speed record.

Major Richard L. Johnson on the day of his record-breaking flight, September 15th, 1948 (

To get the maximum impact, the Air Force decided to make the attempt on the speed record in the full glare of publicity, before a crowd of 80,000 spectators at the 1948 National Air Races in Cleveland, Ohio. The fourth production F-86A-1-NA (serial number 47-608, the cold weather test aircraft) was selected to make the record attempt, and Major Robert L. Johnson was to be the pilot. According to Federation Aeronautique Internationale (FAI) rules, a 3km (1.86 mile) course had to be covered twice in each direction (to compensate for wind) in one continuous flight. At that time, the record runs had to be made at extremely low altitudes (below 165 feet) to enable precise timing with cameras to be made.

On September 5, 1948, Major Johnson was ready to go and flew his F-86A-1-NA serial number 47-708 on six low-level passes over the course in front of the crowd at Cleveland. Unfortunately, timing difficulties prevented three of these runs from being clocked accurately. In addition, interference caused by other aircraft wandering into the F-86A’s flight pattern at the wrong time prevented some of the other runs from being made at maximum speed. Even though the average of the three runs that were timed was 669.480 mph, the record was not recognized as being official by the FAI.

Further attempts to set an official record at Cleveland were frustrated by bad weather and by excessively turbulent air. Major Johnson then decided to move his record-setting effort out to Muroc Dry Lake (later renamed Edwards AFB), where the weather was more predictable and the air less turbulent. On September 15, 1948, Major Johnson finally succeeded in setting an official record of 670.981 mph by flying a different F-86A-1-NA (serial number 47-611, the armaments test aircraft) four times over a 1.86-mile course at altitudes between 75 and 125 feet.

Design

F-86A-1 47-611 Conducting a Static 5-inch HVAR Rocket Firing Test (U.S. Air Force Photo)

The P-86A incorporated as standard some of the changes first tested on the third XP-86 prototype. The front-opening speed brakes on the sides of the rear fuselage were replaced by rear-opening brakes, and the underside speed brake was deleted. However, the most important difference between the P-68A and the three XP-86 prototypes was the introduction of the 4850 lb.s.t. General Electric J47-GE-1 (TG-190) in place of the 4000 lb.s.t. J35. The two engines had a similar size, the J47 differing from the J35 primarily in having a twelfth compressor stage.

The F-86A-1-NA fighters could be recognized by their curved windshields and the flush-fitting electrically-operated gun muzzle doors that maintained the smooth surface of the nose. These muzzle doors opened automatically when the trigger was pressed to fire the guns, and closed automatically after each burst.

The cockpit of the F-86A remained almost the same as that of the XP-86, although certain military equipment was provided, such as an AN/ARC-3 VHF radio, an AN/ARN-6 radio compass, and an AN/APX-6 IFF radar identification set. The IFF set was equipped with a destructor which was automatically activated by impact during a crash or which could be manually activated by the pilot in an emergency. This was intended to prevent the codes stored in the device from being compromised by capture by the enemy. The F-86A was provided with a type T-4E-1 ejection seat, with a manually-jettisoned canopy.

The F-86A-1-NA’s empty weight was up to 10,077 pounds as compared to the prototype’s 9730 pounds, but the higher thrust of the J-47 engine increased the speed to 673 mph at sea level, which made the F-86A-1-NA almost 75 mph faster than the XP-86. Service ceiling rose from 41,200 feet to 46,000 feet. The initial climb rate was almost twice that of the XP-86.

In the autumn of 1948, problems with the J-47-GE-1 engine of the early F-86As forced a momentary halt to F-86 production. It was followed by a few J47-GE-3s, and in December the J47-GE-7 became available, which offered 5340 lb.s.t. and full production resumed.

A close up of the early A models’ retractable gunport covers. (Julien of Britmodeller)

The F-86A-5-NA had a V-shaped armored windscreen which replaced the curved windscreen of the F-86A-1-NA. The A-5 would dispense with the gun doors at some point in its production in the interest of maintenance simplicity, although many A-5 examples can be seen with gun doors, many of them with the doors permanently open. A jettisonable cockpit canopy was introduced. The A-5 introduced underwing pylons capable of carrying a variety of bombs (500 and 1000-pounders) or underwing fuel tanks of up to 206 gallons in capacity. A heating system was provided for the gun compartments, and stainless steel oil tanks and lines were provided for better fire resistance.

In May of 1949, beginning with the 100th F-86A aircraft, an improved canopy defrosting system was installed and a special coating was applied to the nose intake duct to prevent rain erosion. Earlier airframes were retrofitted to include these changes. The 116th F-86A was provided with a new wing slat mechanism which eliminated the lock and provided a fully automatic operation.

Gun Sight & Radar

The P-86A was equipped with the armament first tested on the third XP-86 six 0.50-inch machine guns in the nose, three on each side of the pilot’s cockpit. The guns had a rate of fire of 1100 rounds per minute. Each gun was fed by an ammunition canister in the lower fuselage holding up to 300 rounds of ammunition. The ammunition bay door could be opened up to double as the first step for pilot entry into the cockpit. The P-86A had two underwing hardpoints for weapons carriage. They could carry either a pair of 206.5 US-gallon drop tanks or a pair of 1000-lb bombs. Four zero-length stub rocket launchers could be installed underneath each wing to fire the 5-inch HVAR rocket, which could be carried in pairs on each launcher.

An innovation introduced with the NA-161 production batch was a new type of gun aiming system. All earlier F-86As had been equipped at the factory with Sperry Mark 18 optical lead computing gunsight, which was quite similar to the type of gunsight used on American fighter aircraft in the latter parts of World War 2. When the pilot identified his target, he set the span scale selector lever to correspond to the wingspan of the enemy aircraft he was chasing. He then aimed his fighter so that the target appeared within a circle of six diamond images on the reflector. Next, he rotated the range control unit until the diameter of the circle was the same as the size of the target. When the target was properly framed, the sight automatically computed the required lead and the guns could be fired.

Beginning with the first NA-161 aircraft (49-1007), the A-1B GBR sight and AN/APG-5C ranging radar were provided as factory-installed equipment. This new equipment was designed to automatically measure the range and automatically calculate the appropriate lead before the guns were fired, relieving the pilot of the cumbersome task of having to manually adjust an optical sight in order to determine the range to the target. When activated, the system automatically locked onto and tracked the target. The sight image determined by the A-1B was projected onto the armored glass of the windscreen, and the illumination of a radar target indicator light on the sight indicated time to track target continuously for one second before firing. This system could be used for rocket or bomb aiming as well as for guns.

In the last 24 F-86A-5-NAs that were built, the A-1B GPR sight and AN/APG-5C ranging radar were replaced by the A-1CM sight that was coupled with an AN/APG-30 radar scanner installed in the upper lip of the nose intake underneath a dark-colored dielectric covering. The APG-30 radar was a better unit than the AN/APG-5C, with a sweep range from 150 to 3000 yards. The A-1CM sight and the APG-30 ranging radar were both retrofitted to earlier A-5s during in-field modifications. These planes were redesignated F-86A-7-NA. However, some F-86A-5-NAs had the new A-1CM GBR sight combined with the older AN/APG-5C radar. These were redesignated F-86A-6-NA.

Engines

Some consideration given to replacing the J47 engine with the improved J35-A-17 that was used in the F-84E. This engine was tested in the first XP-86. Flight tests between November 28, 1949 and March 1951 indicated that the performance remained much the same as that of the F-86A-1-NA but with a slightly better range. However, the improvement was not considered significant enough to warrant changing production models.

Some F-86As were re-engined with the J47-GE-13 engine, rated at 5450 lb.s.t., but their designation did not change.

All F-86As were initially delivered with the pitot head located inside the air intake duct. It was found in practice that false airspeed readings could be obtained due to the increased airflow within the intake duct, so North American decided to move the pitot head to the tip of a short boom that extended from the leading edge of the starboard wingtip. All F-86As were later retrofitted with the wingtip boom when went through IRAN (Inspect and Repair as Necessary). However, the pitot tube in the intake was never designed to provide airspeed input to the pilot, and the pitot tube in the intake was still there and was used to provide input for the engine.

Fuel

Internal fuel capacity of the F-86A was 435 gallons, carried in four self-sealing tanks. Two of the tanks were in the lower part of the fuselage, one of them being wrapped around the intake duct just ahead of the engine and the other being wrapped around the engine itself. The other two fuel tanks were in the wing roots. Usually the F-86A carried two 120-gallon drop tanks, although 206.5 gallon tanks could be fitted for ferry purposes.

Weapons

Ground attack weapons could be installed in place of the jettisonable underwing fuel tanks. Choices include a pair of 100, 500 or 1000-pound bombs, 750-pound napalm tanks, or 500 pound fragmentation clusters. Alternatively, eight removable zero-rail rocket launchers could be installed. These mounted sixteen 5-inch rockets. When external armament was fitted in place of the drop tanks, combat radius was reduced from 330 to 50 miles, which was not a very useful distance.

F-86A in Korea

Even though the initial skirmishes with MiGs in Korea had demonstrated that their pilots lacked experience and an aggressive approach, the MiG threat was very real and threw the USAF into a near panic. The USAF had nothing in Korea that could provide an effective counter if the MiG-15s were to intervene in large numbers.

In order to counter the MiG threat, on November 8 the 4th Fighter Interceptor Wing, which consisted of the 334th 335th, and 336th Squadrons, based at Wilmington, Delaware and equipped with the F-86A Sabre was ordered to Korea. Most of their pilots were seasoned veterans of World War 2 and they had shot down over 1000 Germans during that conflict. Prior to flying to the West Coast, the 4th FIG exchanged their older ’48 model F-86As for some of the best “low-time” F-86As taken from other Sabre units. The 334th and 335th FIS flew to San Diego and their planes were loaded aboard a Navy escort carrier. The 336th FIS went to San Francisco and was loaded aboard a tanker. Their F-86A aircraft arrived in Japan in mid-December. The aircraft were then unloaded and flown to Kimpo airfield in Korea.

However, before any of these Sabres could reach the front, on November 26, 1950, Chinese armies intervened with devastating force in Korea, breaking through the UN lines and throwing them back in utter confusion. The MiGs did not provide any effective support for this invasion, being unable to establish any effective intervention below a narrow strip up near the Yalu. The MiG pilots were relatively inexperienced and were poor marksmen. They would seldom risk more than one pass at their targets before they would dart back across the Yalu. Had the MiGs been able to establish and hold air superiority over the battle area, the UN forces may well have been thrown entirely out of Korea.

The first advanced detachment of 336th FIS F-86As arrived at Kimpo airfield south of Seoul on December 15. The first Sabre mission took place on December 17. It was an armed reconnaissance of the region just south of the Yalu. Lt. Col. Bruce H. Hinton, commander of the 336th Squadron, succeeding in shooting down one MiG-15 out of a flight of four, to score first blood for the Sabre. The rest of the MiGs fled back across the Yalu. On December 19, Col. Hinton led another four-plane flight up to the Yalu, where his flight met six MiGs who flew through his formation without firing a shot before dashing back across the Yalu. On December 22, the MiGs managed to shoot down a single Sabre out of a flight of eight without loss to themselves, but later that day the Sabres got their revenge by destroying six MiGs out a flight of 15. This loss spooked the MiG pilots, and they avoided combat for the rest of the month.

During December, the 4th Wing had flown 234 sorties, clashed with the enemy 76 times, scored eight victories, and lost one aircraft.

By the end of 1950, Chinese armies had driven UN forces out of North Korea and had begun to invade the South. The Sabres were forced to leave Kimpo and return to Japan which put them out of range of the action up at the Yalu.

Even though the Yalu was now out of range, on January 14, an F-86A detachment appeared at Taegu to participate as fighter bombers to try to halt the Chinese advance. The F-86A was not very successful in the fighter-bomber role, being judged much less effective than slower types such as the F-80 and the F-84. When carrying underwing ordinance, the F-86A’s range and endurance were much too low, and it could not carry a sufficiently large offensive load to make it a really effective fighter bomber. In these attacks, the underwing armament was usually limited to only a pair of 5-inch rockets.

Eventually, the Chinese advance ground to a halt due to extended supply lines and the relentless UN air attacks. The Chinese advance was halted by the end of January, and the UN forces began pushing them back. Kimpo airfield was recovered on February 10. The halting of the Chinese advance can be blamed largely on the inability of the MiGs to provide any effective support for the Chinese attack. Not only had no Chinese bombers appeared to attack UN troops, but no MiGs had flown south of the Yalu region to provide any air support.

The Chinese apparently did have plans for a major spring offensive to complete the task of driving the UN out of Korea. This plan was to be based on the construction of a series of North Korean air bases and for Chinese MiGs to use these bases as forward landing strips to provide air superiority over the North, preventing UN aircraft from interfering with the advance.

In early March, the MiGs began to become more active in support of this offensive, On March 1, MiGs jumped a formation of nine B-29s and severely damaged three of them. Fortunately, by this time the UN base at Suwon was now ready, and the Sabres were now able to return to Korea and reenter the fray over the Yalu. The Sabres of the 334th Squadron began their first Yalu patrols on March 6th, and the rest of the squadron moved in four days later. At the same time, the 336th Squadron moved to Taegu from Japan, so that they could stage Sabres through Suwon. The 4th Wing’s other squadron, the 335th, stayed in Japan until May 1.

MiG Alley

The strip of airspace in western Korea just south of the Yalu soon became known as “MiG Alley” to the Sabre pilots. The Sabres would arrive for their 25-minute patrols in five minute intervals. The MiGs would usually cruise back and forth at high altitude on the other side of the Yalu, looking for an opportune time to intervene. Very often they would remain on the north side of the river, tantalizingly out of reach. When the MiGs did choose to enter battle, the Sabres would usually have only a fleeting chance to fire at the enemy before the MiGs broke off and escaped back across the Yalu. The MiGs had the advantage of being able to choose the time and place of the battle. The MiG-15 had a better high-altitude performance than the F-86A. The MiG had a higher combat ceiling, a higher climb rate, and was faster at higher altitudes than the F-86A. Its superior high-altitude performance enabled the MiG to break off combat at will. Despite these handicaps, the F-86A pilots were far more experienced than their Chinese opponents and they were better marksmen. The Sabre was a more stable gun platform and had fewer high-speed instabilities than did the MiG-15. In addition, the F-86A was faster than the MiG-15 at lower altitudes, and an effective strategy was for the Sabre to force the battle down to lower altitudes where it had the advantage.

In April of 1951, the MiGs got a little bolder, and they would often make attempts to intercept B-29 formations that were attacking targets in the Sinuiju area up near the Yalu. The biggest air battle of that spring took place on April 12, when a formation of 39 B-29s escorted by F-84Es and F-86As were attacked by over 70 MiGs. Three B-29s were lost, whereas 14 MiGs were claimed destroyed, four by the escorting Sabres and ten by B-29 gunners.

On May 20, 1951, F-86A pilot Captain James Jabara became the world’s first jet ace when he shot down a pair of MiGs to bring his total to six.

No F-86As were lost in action during the first five months of 1951, and they flew 3550 sorties and scored 22 victories. Most of the attrition was caused by accidents rather than by losses in actual combat.

In June of 1951, the MiGs began to show more aggressive behavior, and their pilots began to get somewhat better. In air battles on June 17th, 18th, and 19th, six MiGs were destroyed but two Sabres were lost. Another Sabre was lost on June 11 when the 4th Wing covering an F-80 attack on the Sinuiju airfield shot down two more MiGs.

As the first year of the Korean War came to an end, it was apparent that the Sabre had been instrumental in frustrating the MiG-15’s bid for air superiority. Without control of the air, the Red Chinese were unable to establish their series of air bases and they were not able to carry out effective air support of their spring offensive, and the Korean War settled down to a stalemate on the ground.

The more-advanced F-86E began to enter action in Korea with the 4th Wing in July of 1951, replacing that unit’s F-86As on a one-by-one basis. The conversion to the F-86E was rather slow, and the last F-86A was not replaced until July of 1952.

Operators

  • U.S. Air Force – The U.S. utilized the F-86A extensively for the air defense of the Continental United States, while also seeing action in Korea in MiG Alley.

North American F-86A-5-NA Specifications

Wingspan 37 ft 1.5 in / 11.32 m
Length 37 ft 6.5 in / 11.44 m
Height 14 ft 9 in / 4.5 m
Wing Area 287.9 ft² / 26.8 m²
Engine 1x General Electric J47-GE-13 Turbojet Engine

5200 lbst

Weights
Empty 10,093 lb / 4,578 kg
Maximum Take Off 14,108 lb / 6,399 kg
Combat 13,791 lb / 6,255 kg
Climb Rate
Rate of Climb at Sea Level 7,470 ft / 2,277 m per minute
Time to 40,000 ft / 12,192 m 10.4 minutes
Maximum Speed
Sea Level 679 mph / 1,092 kmh
35,000 ft / 10,668 m 601 mph / 967 kmh
Takeoff Run 2,430 ft / 741 m
Range (with Drop Tanks) 660 mi / 1,062 km
Maximum Service Ceiling 48,000 ft / 14,630 m
Crew 1 pilot
Armament
  • 6x Browning M3 machine guns, 300 rounds per gun
  • A-1B GBR Gun Sight
  • AN/APG-5C Ranging Radar
  • 8x 5-inch HVAR Rockets
  • 2x 1000 lb bombs
  • 2x Drop Tanks – 206.5 U.S. Gal / 781.7 Liters

Gallery

Illustrations by Ed Jackson

F-86A-1 Sabre 47-611 – September 1948
F-86A-1 Sabre 47-630 – 1948
F-86A-5 48-0158 – 1949
F-86A-5 48-1257 – Korea 1951 – Flown by Capt. James Jabara
F-86A-5 Sabre 49-1080 February 1952 – Note the 5 inch HVAR Rocket Mounted inboard of the fuel tank

Sources:

  1. F-86 Sabre in Action, Larry Davis, Squadron/Signal Publications, 1992.
  2. The North American Sabre, Ray Wagner, MacDonald, 1963.
  3. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
  4. The World Guide to Combat Planes, William Green, MacDonald, 1966.
  5. Flash of the Sabre, Jack Dean, Wings Vol 22, No 5, 1992.
  6. North American F-86 Sabre, Larry Davis, Wings of Fame, Volume 10, 1998