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Northrop X-4 Bantam

During World War II, engineers in the U.S. and UK studied semi-tailless aircraft, and the German Luftwaffe fielded the semi-tailless Me 163 (one of which is on display in the museum’s World War II Gallery). After the war ended, Northrop built two X-4s to test if this configuration could perform at transonic (near-supersonic) speeds better than conventional aircraft.

Flight testing of the X-4 began in 1948, and in 1950 both X-4s were turned over to the NACA (National Advisory Committee for Aeronautics), predecessor to NASA (National Aeronautics and Space Administration). The first X-4 was grounded after only 10 flights, and only the second X-4 (on display at the museum) was used in the joint USAF/NACA program. Instability of the X-4 at high speed led to the conclusion that semi-tailless aircraft were not suitable for transonic flight (with the technology then available).

The X-4 on display was transferred to the museum shortly after the program ended in 1953. It was restored by the Western Museum of Flight, Hawthorne, Calif.

Two Westinghouse XJ30 turbojet engines of 1,600 lbs. thrust each
Maximum speed: 640 mph
Maximum endurance: 44 minutes
Service ceiling: 44,000 feet

Click here to return to the Research & Development Gallery.


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View the X-4 on Display
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View the X-4 Cockpit
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