Scramjet: Your New Speed Overlord
The U.S. Air Force’s experimental X-51A Waverider set a hypersonic flight record when it flew at Mach 5 — five times the speed of sound — for more than three minutes. The previous scramjet record was a paltry 12 seconds. Air Force officials called the test, the first of four planned, an unqualified success.
An X-51A Waverider flight-test vehicle successfully made the longest supersonic combustion ramjet-powered hypersonic flight May 26 off the southern California Pacific coast. Hypersonic flight, normally defined as beginning at Mach 5, five times speed of sound, presents unique technical challenges with heat and pressure, which make conventional turbine engines impractical. Program officials said producing thrust with a scramjet has been compared to lighting a match in a hurricane and keeping it burning.
As planned, the X-51A separated from the B-52 at 50,000 feet, where the solid rocket boosters accelerated the engine to about Mach 4.8. At this point the booster and support were jettisoned and the scramjet did kicked into badass territory and accelerated to a speed above Mach 5, which is approximately 4,000 MPH, for more than three minutes. To put it another way: the X-51A traveled approximately 200 miles in three minutes. Previously, NASA managed a 12-second flight with their X-43 rocket.