In 1946 the new Strategic Air Command of the USAAF placed an order for the development of a so-called penetration fighter; a long-range fighter able to fly ahead of the bomber force and sweep aside all fighter opposition. The XF-90 evolved over two years and resulted from 65 different designs created by Johnson's engineers. These included butterfly-tailed aircraft, three-engine aircraft, 'W' winged designs. Lockheed’s Model 153 submission was thought to offer great potential and was ordered in the form of two XF-90 prototypes. The two prototypes were to be tested in a fly-off competition with the McDonnell XF-88 and North American YF-93A designs.
Developed by Clarence L. (Kelly) Johnson's Lockheed fighter team, the design had a number of similarities to the company’s F-80 Shooting Star, but was of more advanced aerodynamic concept. It had a finely tapered forward fuselage, two laterally mounted 4200-lb (1905-kg) afterburning thrust Westinghouse J34-WE-11 turbojets, and flying surfaces swept at 35 degrees. A radius of about 1100 miles (1770-km) was provided by considerable internal fuel supplemented by jettisonable wingtip tanks. This was calculated to provide an escort capability into the western USSR from bases in West Germany, and a potent offensive punch was provided by a combination of four 20-mm cannon with six 0.5-in (12.7-mm) machine-guns. The final XF-90 had 12.7mm rivets in the wings and weighed as much as a DC-3.
The first aeroplane flew in June 1949, and was immediately revealed to be drastically under-powered with twin 1406kg thrust Westinghouse J34-WE-11 turbojets. The XF-90 reached 1070km/h at 9784m in level flight and could easily be pushed through the sound barrier in a shallow dive. Throughout April and May 1950, above Muroc Dry Lake, Lockheed test pilot Tony LeVier put the XF-90 through high-speed dive tests. LeVier dived the XF-90 to Mach 1.12 on 17 May 1950.
The XF-90 stalled at 204km/h, making it no easy machine to control on the approach. Its take-off performance enabled it to clear a 15m obstacle in 2629m without the rocket-assisted take-off (RATO) units used in some tests. In the 1949 fly-off, the XF-88 came in first, the XF-90 second, and the YF-93A third, but by then the results were academic. With the September 1949 detonation of the Soviet Union's first nuclear weapon, the USAF’s requirement was changing at this time, so the project was cancelled.
The second XF-90 was rigged with instruments on the ground and destroyed in the 1952 atomic bomb tests at Frenchman's Flat, Nevada. Lockheed records indicate that the first XF-90 was shipped in 1953 to a National Advisory Committee for Aeronautics (NACA) laboratory in Cleveland, Ohio. Apparently, it was eventually broken up in tests at that NACA facility.
Engines: 2 x Westinghouse J34-WE-11 turbojets, 1406kg thrust
Max take-off weight: 12300 kg / 27117 lb
Empty weight: 8400 kg / 18519 lb
Wingspan: 12.19 m / 39 ft 12 in
Length: 17.12 m / 56 ft 2 in
Height: 4.8 m / 15 ft 9 in
Wing area: 32.05 sq.m / 344.98 sq ft
Max. speed: 1070 km/h / 665 mph
Ceiling: 11800 m / 38700 ft
Range: 3700 km / 2299 miles