Lockheed Martin X-35

The Lockheed Martin X-35 is the concept demonstrator aircraft that Lockheed Martin built for the Joint Strike Fighter program, which in 2001 beat the Boeing X-32 and led directly to the F-35 Lightning II. Two airframes were flown: the X-35A, later converted into the X-35B short take-off and vertical-landing demonstrator, and the larger-winged X-35C for carrier trials. Both used power plants derived from the Pratt and Whitney F119, and the X-35B added a shaft-driven lift fan developed with Rolls-Royce. The X-35A first flew on 24 October 2000 and the X-35C on 16 December 2000. The demonstrators proved concepts rather than carrying the internal structure of the production fighter, and surviving aircraft now sit in museums.