Aircraft
Scramjet Stalls, X-Plane Crashes on Second Flight
A second test flight of the X-51A WaveRider has not gone according to plan.
The diminutive, hypersonic X-51A, an unmanned, scramjet-powered aircraft, is dwarfed by the B-52 carrier aircraft as the latter taxies before takeoff from Edwards AFB for the second test flight on June 13. (Photo: U.S. Air Force)
The diminutive, hypersonic X-51A, an unmanned, scramjet-powered aircraft, is dwarfed by the B-52 carrier aircraft as the latter taxies before takeoff from Edwards AFB for the second test flight on June 13. (Photo: U.S. Air Force)

A second test flight of the X-51A WaveRider has not gone according to plan. Successfully dropped from the left wing of a B-52H Stratofortress, and then accelerated to over Mach 5 by a solid rocket booster, the unmanned, scramjet-powered, hypersonic vehicle crashed in the Pacific Ocean off Point Mugu NAS, Calif. on June 13

The WaveRider’s first flight on May 26, 2010, also faltered. The aircraft flew for more than 200 seconds powered by its Pratt & Whitney Rocketdyne scramjet motor–the longest scramjet powered flight in history. It reached an altitude of 70,000 feet and approximate speed of Mach 5. “Something then occurred that caused the vehicle to lose acceleration,” the Air Force said at the time. “At that point, the X-51A was terminated as planned.”