Case Studies in the Achievement of Air Superiority - Air Force ...

KOREA
in the brief interval that F-86 pilots usually had to make a In June of
that year, 4th Fighter-Interceptor Group renewed its request for a more
powerful armament and also asked for a lighter aircraft.86 Lightening the
F-86 to make it more maneuverable was an option that had already been
considered and rejected.87 Like all military aircraft designs, that of the
F-86 was a strict compromise. To increase the F-86’s rate of climb and
maximum speed, engineers could give the plane a more powerful engine, or
cut its weight, or both. But they could not reduce the plane’s weight without
also reducing some other important military characteristics, such as
endurance or armament load. The F-86 was not designed to be a daylight
air superiority fighter. It was developed as an all-purpose fighter-bomber.
Any serious redesign would in fact become an entirely new aircraft.
Fifth Air Force had recovered parts of a MiG-15 as early as April
1951.88 It was soon clear that the F-86 could not be modified to the same
design standards. However, fighter pilots continued to demand F-86 flight
improvements and new guns and gunsights. General Partridge, who had left
Fifth Air Force in June 1951 to head the Air Research and Development
Command (ARDC). was well aware of the pilots’ concerns. He routinely
read Fifth Air Force operations reports and intelligence summaries, and he
also reviewed reports filed by North American Aviation on F-86 improvement~.~~
In January 1952, USAF Headquarters directed ARDC to begin a
comprehensive program to better the combat performance of the F-86. Partridge
assigned the management of the task to the Wright Air Development
Center, and intensive work began on improving the F-86’s rate of climb at
the beginning of February. By the end of May, some solutions were ready
for trial.g0 The most significant was one suggested first by North American
engineers: sealing the leading edge slats on the Sabre’s wings. Kits to convert
the F-86’s wings to the new configuration were combat tested in Korea
by the 4th Fighter-Interceptor Wing in July 1952 with impressive results,
and gradually all the earlier Sabre models were converted to the new wing
configuration. At the end of June 1952, 4th Wing squadrons received the
first production models of the new variant, the F-86F.
That the solid leading-edge F-86F’s were in combat was one of the best-kept USAF
secrets, and the modification was mysteriously mentioned in American newspapers
as the “new secret device” and the “new combat device” which was giving
increased MiG kills.91
What it also produced were higher landing speeds. The original F-86s were
designed with slats at their wings’ leading edges that changed the wings’
configuration with the speed of the airplane to give the swept-back fighter
sufficient lift for lower speed landings. The swept-back wings reduced
drag at high speeds but cost the aircraft lift at slower speeds, and the
variable leading edges had been developed by German designers at the
end of World War I1 to reduce the stall speeds of swept-back designs.
It was a matter of compromise: to improve low-speed stall charac-
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