Newest addition to the USAF jet penetration fighter stable, the swept-wing North American YF-93A flew for the first time last week at Edwards AFB, Muroc, Calif., and immediately became a strong contender for quantity USAF procurement although currently only two of the planes have been ordered.
The powerful new craft made a JATO takeoff and flew for 43 min. on its first trip aloft.
The 10-ton fighter, nearly twice as heavy as its earlier relative, the 13,000- lb. North American F-86, is powered with a new Pratt & Whitney J-48 turbo-Wasp engine, American development of the British Tay design, rated at 6250 thrust Ib. dry, and about 8000 Ib. with afterburner,
Comparison of dimensions with those of the F-86 shows clearly that the new long-range fighter is a much larger airplane. Wingspan is 39 ft. as compared to 37 for the F-86; fuselage length is 44 ft. as compared to 37 ft., while height is 16 ft. as compared to 14 ft.
Twin flush air intake ducts just above and forward of the wingroots are precisely tailored into the sides of the fuselage, leaving the nose clear to house interceptor radar. (The F-86 has a single intake duct in the center of the nose.)
Exceptionally large boundary layer bleeds are visible at the intake ducts. Smaller flush air intake ducts near the tail apparently serve as a cooling arrangement.
Single-wheel nosegear retracts for- ward into the nose, while small diameter twin-wheeled main gear retracts inboard into the wingroots.
Automatic wing slots and slotted type flaps are provided.
Fuselage diameter appears consider- ably greater than that of the F-86, presumably to enclose the larger diameter of the centrifugal-flow type J-48 which replaces the slimmer axial-flow type GE J-47.
Tail surfaces are swept back like those of the F-86, and are slightly larger, in keeping with the general scaling up of the YF-93A.
As a more powerful development of the first tactical combat plane to fly faster than the speed of sound (AVIATION WEEK, June 14, 1948), the YF-93A is described by USAF as "designed to reach high sub-sonic speed." an apparent understatement of the new plane's obvious real capabilities, when its re- duced drag and greater power is considered.
The F-86 is currently the Air Force's top standard jet fighter, with approximately 800 planes on order or delivered. The plane still holds the world's speed record of 670.98 mph. But North American announced recently that new production F-86s are exceeding this official record almost daily in acceptance tests at Los Angeles.
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