Bell X-4


X-4 In Flight

First Flight: December 15, 1948
Mission: Determine stability of swept-wing, tail-less aircraft
Major Accomplishments: Provided data regarding flight characteristics of thin wing/high aspect ratio wings

Power Source: Two (2) Westinghouse J30-WE-7-9 turbojets
Wing Span: 26ft 10 in (8.18m)
Length: 23ft 3 in (7.10 m)
Maximum Achieved Speed: Mach 0.89

Additional Information: Two X-4s were built. Northrop hired Charles Tucker and Chuck Yeager for 30 test flights. The planes where turned over to the NACA, who made an additional 60 flights with the planes. Both planes survive, one is housed at the Air Force Museum in Dayton the other at the Air Force Academy in Colorado Springs.


X-4 as displayed at the USAF Museum
Image courtesy of the USAF Museum