Originally posted by Delirium
Ok, here is another question along the same lines;
How is the F86's wing slats compared to the 109? Same mechanism or was a completely different design?
Greg Goebel makes the following interesting comments.
F-86 swept wing and slats "This [early P-86] design got as far as a full-scale partial wooden mockup, unveiled at the NAA Inglewood, California, plant on 20 June 1945. It went no further, since by this time North American engineers knew that there was no way it could meet USAAF requirements. The straight wing couldn't achieve the required speed with the engines available at the time.
Aircraft engineers knew that a thin swept wing could greatly reduce drag and delay the onset of compressibility problems, but such a wing also led to serious stability problems at low speed. The hard data needed to resolve the issue was not available until early 1945, when the Allies captured research data on swept-wing flight from the Germans.
The Germans had conducted wind-tunnel tests on small swept-wing aircraft models as far back as 1940. By 1944, their work had demonstrated that swept wings offered substantial performance benefits. The main difficulty was that any swept wing that was efficient at high speeds tended to be unstable at low speeds. They experimented with a number of ways to deal with this problem, one of the most promising being a "slat" on the leading edge of the wing, which could be raised to change the airflow and generate more lift.
After the end of the war, aviation engineer George Schairer of the Boeing Company went to Germany to examine German aviation research. He was accompanied by the well-known Theodore Von Karman of the California of Technology, and Robert Jones of the US National Advisory Committee on Aeronautics (NACA, one of the precursor organizations of the modern US National Aeronautics & Space Administration / NASA). Schairer was extremely enthusiastic about the data he found on swept-wing flight, and not only proposed that Boeing use it on their new XB-47 long-range bomber, but that the information be provided to other US aviation firms.
Larry Green of NAA studied the materials and came to the conclusion that a swept wing was answer to improving the performance of the XP-86, and determined that a slat attached to the wing's leading edge and automatically extended at low speeds would solve the low-speed stability problem. Green and other NAA engineers convinced the president of NAA, "Dutch" Kindelberger, that the swept wing was the way to go, and on 18 August 1945, Kindelberger approved further studies on the concept. Within a few weeks, NAA engineers were performing wind tunnel tests on a 1/23rd scale model of an XP-86 with wings swept at 35 degrees. The results were extremely promising. After further tests, the USAAF approved development of the swept-wing XP-86 on 1 November 1945.
* Models were one thing, a flying aircraft another. Engineering the slats was troublesome, and in fact the NAA team went so far as to obtain slatted wings from the German Messerschmitt 262 jet fighter to get ideas.
The first seven aircraft would actually use some Messerschmitt 262 slat hardware. ---
The first production batch of 33 aircraft was designated "F-86A-1". The second production batch of 188 was designated "F-86A-5", and featured a number of enhancements. While the F-86A-1 had a rounded front windscreen, the F-86A-5 had a flat front armor glass windscreen, and the canopy was now jettisoned using pyrotechnic charges. An improved leading-edge slat scheme was introduced, and there were a number of minor internal changes.
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North American had only begun tinkering with the wing, however. Aerodynamic studies had shown that eliminating the leading-edge slat and providing a sharper leading edge on the wing provided substantial benefits in high-speed flight, though this led to "hotter" landing characteristics. To compensate for the hot landings, the wing was extended 15 centimeters (6 inches) at the root and 7.6 centimeters (3 inches) at the wingtip. The new wing, which also featured fuel tanks in the leading edge that increased capacity by 264 liters (70 US gallons), was known as the "solid 6-3" wing. The wing was incorporated into F-86F-25/30 production in midstream, and was also sent to Korea in kit form to upgrade most F-86Fs and a few F-86Es in service there.
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The A-4 Skyhawk also used slats as well.
All the best.
