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...Republished from our Flight Manual
In 1945 North American Aviation, already famous for its P-51 Mustang and B-25 Billy Mitchell bomber, was put under contract by the US Army Air Force (USAAF) to produce a new jet fighter utilizing information derived from captured German data for the Messerschmitt Me 262. These innovative technologies were employed in transforming the straight-winged US Navy XFJ-1 into the XP-86 Sabre. It made its first flight on October 1, 1947 flown by North American chief test pilot George S. Welch who, in a high speed dive from 35,000 feet, broke the sound barrier 14 days before Chuck Yeager went supersonic in level flight flying the rocket powered Bell X-1. The first production F-86A-1 for the re-designated United States Air Force (USAF) flew on May 20, 1948. On September 15, 1948, an F-86A set a new world speed record of 670.97 mph.
Originally designed as a high-altitude day fighter, the F-86 Sabre would undergo a number of changes during its operational use resulting in 20 different variants (including the US Navy FJ series known as the Fury). Some variants had major differences such as the F-86H designed to be a fighter bomber and the F-86D designed as an all-weather interceptor, thus the “Sabre” was really a whole family of related aircraft. These variants represented many firsts in design and technology. Their original swept-wing configuration has since become a standard for jet aircraft and later models had a revolutionary but now commonplace “all flying” horizontal tail section that allowed the aircraft excellent maneuverability at high altitudes. Sabre’s also employed a hydraulic system for the movement of the flight controls to eliminate the excessive control stick forces necessary for a pilot to maneuver other types of aircraft at high speeds. The F-86D model was the first fighter jet to have an autopilot.
Identifying features of the Sabre are its 4.78 aspect-ratio wing with a 35° sweepback and the air inlet located in front of the nose. Stream wise airfoil-section thickness ratios varied from 9.5 percent at the root to 8.5 percent at the tip. Pitch-up was prevented on some models by full-span leading-edge wing slats on the F-86E and F models as on the Me 262. Deployment of the slats was automatically initiated at the correct angle of attack by aerodynamic loads acting at the leading edge of the wing. On later versions of the aircraft the slats were replaced by a sharp extended-chord cambered leading edge. Single-slotted high-lift flaps and outboard ailerons were incorporated in the trailing-edge portions of the wing. The ailerons were hydraulically actuated as was the first horizontal “all-flying” tail assembly on the F-86E which meant the entire stabilizer could be rotated in conjunction with a linked elevator. With the horizontal all-flying tail greater control effectiveness is possible at high-subsonic and supersonic Mach numbers. Even later versions of the Sabre had an all-moving, slab-type horizontal all-flying tail with no elevator. This arrangement has since become standard on all transonic/supersonic fighters.
The hydraulically actuated controls of the F-86E and F models were of the fully powered, irreversible type with an artificial control feel system to aid in eliminating such instabilities as aileron and rudder buzz to permit maximum deflection of the control surfaces without requiring excess physical effort on the part of the pilot. These controls differ from the hydraulically boosted controls used on the F-86A. In a boosted control system, the pilot is still directly linked to the aerodynamic control surfaces, but his strength is augmented by a hydraulic booster. Dive brakes were also mounted on either side of the fuselage behind the wing. Later versions of the Sabre, notably the F-86D, K and L models had an afterburner. Another identifying feature of the pre-afterburner versions of the F-86 was the fuselage nose-inlet installation. Inlet air was ductedunder the cockpit and delivered to the turbojet engine located behind the pilot with an exhaust nozzle at the rear end of the fuselage. To minimize the depth of the fuselage in the cockpit area, the shape of the duct leading from the inlet to the engine was changed from a circular to an elliptical shape with the long axis being in the horizontal plane. Environmental control in the cockpit consisted of air-conditioning, heating, and pressurization.
The thrust-to-weight ratio of the F-86 was about the same as that of the World War II P-59A. Yet, as compared to it, the first Sabre showed a speed advantage of nearly 300 miles per hour at sea level. A smaller wing area, wing sweepback, and thinner airfoil sections, together with careful attention to aerodynamic design, were responsible for the large increment in maximum speed between the two types. Improved engine function also played a role in the superior performance of the Sabre. Drag area was a little greater than for the F-80 by an amount that corresponds closely to the difference in wing area of the two aircraft. As would be expected, the zero-lift drag coefficients were about the same for both aircraft; however, comparison of values of the maximum lift-drag ratio showed the F-80 to have had the advantage by about 17 percent which was primarily due to the lower wing aspect ratio of the F-86.
The F-86 Sabre was best known for its combat role as an air superiority day fighter during the Korean War (1950-1953). First arriving at Kimpo airfield near Seoul, Korea on December 15, 1950 the Sabre saw extensive service not only as a fighter near the beginning of the war but also as a fighter-bomber during the latter stage of the war. Armament consisted of three .50-caliber M3 machine guns buried in each side of the fuselage near the nose. In three successive series (F-86A, E, and F) it challenged the (initial) tactical edge of Russian built Mikoyan/Gurevich MiG-15s mixing it up over northwest Korea, an area known as "MiG Alley." The MiG pilots were good, being (for the most part) World War Two veteran Russian fliers; however, many of the Sabre pilots were also veterans of World War Two and their expertise showed. On December 17, 1950, Lt. Colonel Bruce H. Hinton scored the first MiG-15 kill by a Sabre pilot. On May 20, 1951 Captain James Jabara became the world’s first (Sabre) jet ace.
When the Korean War turned into a stalemate on the ground (July 1951-July 1953), USAF B-29s continued bombing targets in northwest Korea by day, but after MiGs shot down five in one week during October 1951, the big bombers began attacking only at night. On the other hand “MiG Alley” remained a hot spot throughout the conflict. Day after day Sabre’s swept into MiG Alley to meet MiGs which were based at airfields located in Manchuria just across the Korean border along the Yalu River. Although the United Nations had directed that the Manchurian airfields were "off limits" to USAF aircraft, some (aggressive) F-86A pilots occasionally ‘strayed’ into that sanctuary while in hot pursuit of prey.
In July 1951 the F-86E with leading edge slats entered the war, followed in June 1952 by the F-86F-10 also with slats. Next came the F-86F-30 with a change to wing design that let to the famous “6-3” wing in which the leading edge slats were deleted in favor of a new solid leading edge with 6-inches more chord at the root near the fuselage and 3-inches more length at the wing tip. A five inch high boundary layer "fence" was also added to the upper surface of the wing at 70% of the wingspan to direct air flow. These changes resulted in a lower drag coefficient and added seven miles per hour to the top speed. Maneuverability also improved at high altitude due to a delay in the onset of buffeting which enabled the Sabre to now turn inside a MiG. Top speed was 695 mph, climb rates increased 300 feet per minute and operating altitude increased in excess of 48,000 feet. Termed “viceless” by the men who flew the F-86F because it had to be forced into a spin and could recover simply by neutralizing the controls, it became the definitive Sabre. Flyaway cost was $211,111 (US) in 1952. Factored for inflation that would be $1,645,356 in 2007 … a real bargain for a front line jet fighter.
Even with its upgrades during the Korean War a F-86 Sabre pilot still had to be in visual contact with the enemy in order to attempt a shoot-down thus it was the last true 'dogfighter' in USAF inventory. It single-handedly turned the tide of the air war in Korea in favor of the USAF byshooting down 792 MiGs at a loss of 78 Sabre’s, a victory ratio of 10 to 1 and the highest ever achieved by a fighter in any sustained air campaign. Of the 40 USAF pilots to earn the designation title of 'ace' (five or more kills) 39 flew the Sabre, and by the end of the war (July 27, 1953) no fighter in the world could take on an F-86 without being at a disadvantage. In that regard it must be ranked, along with its illustrious WWII ancestor the P-51 Mustang, as one of the greatest fighter aircraft of all time.
After the Korean War, Warner Robins Air Logistics Center (WR-ALC) had logistics management responsibility for the guns, communications, fire control and bombing-navigational equipment installed on F-86 aircraft. From 1953 to 1958, under Project High Flight, more than 500 Sabre’s were processed through the WR-ALC maintenance shops to prepare them for ferrying across the Atlantic to USAF bases in Europe or to other NATO allies.
Under license, production lines for F-86 Sabre day fighters were established in four foreign countries, Canada, Australia, Japan, and Italy. During the years 1947 through 1961, before production ended, a total of 8,745 were manufactured with five different engines making it the most prolific jet fighter ever produced. Of the total, 6297 were built in the U. S. and 1815 in Canada. The last Sabre to be produced rolled off the Mitsubishi of Japan assembly line in 1961.
Ultimately surpassed in performance during the second half of the 1950’s by the newer Century Series of Fighters, the F-86 Sabre has long been retired from the operational inventory of the USAF but as late as 1996 a number continued to be used for various military flight-test purposes or as US Army target drones. During its Foreign Service life, the Sabre was a part of the air forces for 24 different countries including Australia, Britain, Nationalist China, Pakistan, Republic of Korea, Spain and West Germany. As late as 1980, eight developing nations still had a number of Sabre’s in their inventory. The last military active Sabre, an F-86F, was withdrawn from Bolivian service in 1993, fully forty-one years after it was built. At least one manufacturer, the Boeing Company, used an F-86 as a project chase plane into the early 1990’s. Of all Sabre variants held by private owners and museums that are still flying today the "F" model with leading edge slats survives in the greatest number.
Learn more from Wikipedia about the Sabre.