On 1 May 2013, the X-51 performed its first fully successful flight test on its fourth test flight. The X-51 and booster detatched from a B-52 and was powered to Mach 4.8 by a booster rocket. It then separated cleanly from the booster and ignited its own engine, accelerating to Mach 5.1. The flight lasted for 240 seconds until it ran out of fuel, breaking the record for longest air-breathing hypersonic flight. Researchers collected flight telemetry data for 370 seconds. The Air Force Research Laboratory believes the successful flight will serve as research for practical applications of hypersonic flight. This test signified the completion of the program.
No wonder they called it the Flying Circus. WW1 Albatros.
This camo is too awesome.