The Boeing X-51 is an unmanned scramjet demonstration aircraft for hypersonic (Mach 6 approximately 4 000 miles per hour at altitude) flight testing. It successfully completed its first free-flight on 26 May 2010 and also achieved the longest duration flight at speeds over Mach 5. The X-51 Waverider program is run as a cooperative effort of the United States Air Force DARPA NASA Boeing and Pratt & Whitney Rocketdyne.
Made by Boeing.