U.S. TESTED WORLD FIRST HYPERSONIC WEAPON
The Boeing X-51 (or X-51 WaveRider) is an unmanned research scramjet aircraft for hypersonic flight at Mach 5 (3,300 mph; 5,300 km/h), an altitude of 70,000 feet (21,000 m). The aircraft was designated X-51 in 2005. It completed its first powered hypersonic flight on 26 May 2010. After two unsuccessful test flights, the X-51 completed a flight of over six minutes and reached speeds of over Mach 5 for 210 seconds on 1 May 2013 for the longest duration powered hypersonic flight.
Waverider refers in general to aircraft that take advantage of compression lift produced by their own shock waves. The X-51 program was a cooperative effort by the United States Air Force, DARPA, NASA, Boeing, and Pratt & Whitney Rocketdyne. The program was managed by the Aerospace Systems Directorate within the U.S. Air Force Research Laboratory (AFRL). X-51 technology is proposed for use in the High Speed Strike Weapon (HSSW), a Mach 5+ missile which could enter service in the mid-2020s.
DARPA once viewed X-51 as a stepping stone to Blackswift, a planned hypersonic demonstrator which was canceled in October 2008. In May 2013, the U.S. Air Force plans have X-51 technology applied to the High Speed Strike Weapon (HSSW), a missile similar in size to the X-51. The HSSW could fly in 2020 and enter service in the mid-2020s. It is envisioned to have a range of 500-600 nmi, fly at Mach 5-6, and fit on an F-35 or in the internal bay of a B-2 bomber.