The twin-turbojet X-3, the only one built, was designed to test sustained flight at twice the speed of sound. It also explored the use of very short wings and titanium airframe construction. Engine development difficulties forced the use of lower-powered engines than originally planned, prohibiting the X-3 from achieving its Mach 2 design potential. Even so, data gained from the X-3 program greatly benefited the F-104, X-15, SR-71 and other high performance aircraft. The X-3 made its first test

The twin-turbojet X-3, the only one built, was designed to test sustained flight at twice the speed of sound. It also explored the use of very short wings and titanium airframe construction. The X-3 made its first test flight at Edwards Air Force Base, Calif., in October 1952. The X-3 was transferred to the museum in 1956. TECHNICAL NOTES: Engines: Two Westinghouse J34s of 3,370 lbs. thrust each (4,900 lbs. thrust with afterburner) Maximum speed: 650 mph (level flight), but designed for Mach 2 S