May 26, 2010

USAF’s X-51A unmanned hypersonic air vehicle makes first flight, flying further on its own power than any other scramjet in history. A B-52 mothership carried aloft the Boeing-built X-51, which flew at Mach 5 for about 200 seconds before program officials terminated the flight. Pratt & Whitney- Rocketdyne developed the vehicle’s revolutionary SJY61 engine. USAF officials later revealed that testers had to prematurely terminate the flight because of a breached seal in the interface between the air vehicle and its engine.