The Lockheed XF-90 was built in response to a United States Air Force requirement for a long-range penetration fighter and bomber escort. The same requirement produced the McDonnell XF-88 Voodoo. Lockheed received a contract for two prototype XP-90s. The design was developed by Willis Hawkins and the Skunk Works team under Kelly Johnson. Two prototypes were built. Developmental and political difficulties delayed the first flight until 3 June 1949, with Chief Test Pilot Tony LeVier at the controls. Embodying the experience gained in developing the P-80 Shooting Star, the XF-90 shared some design traits with the older Lockheed fighter, albeit with swept-wings; however, this latter design choice could not sufficiently make up for the project’s underpowered engines, and the XF-90 never entered production.

The McDonnell XF-88 Voodoo was a long-range, twinjet fighter aircraft with swept wings designed for the United States Air Force. Although it never entered production, its design was adapted for the subsequent supersonic F-101 Voodoo.