To the X-51A hypersonic vehicle program.
Looks like the fourth time’s the charm. After a trio of attempts at sustained air-breathing hypersonic flight, the DARPA/Air Force Research Lab/Boeing/Pratt & Whitney Rocketdyne team behind the X-51A Waverider notched a solid success. On May 1, the missilelike vehicle dropped from a B-52 off California, rode a rocket booster past Mach 4, and then lit up a scramjet that pushed it to Mach 5.1 for several minutes before it ran out of JP-7 fuel and fell as planned into the Pacific.
It was the final flight of the $300 million program, launched in 2004 to restart serious inquiry into hypersonic flight — a field whose most celebrated advances came in the X-15 rocket plane program a half-century ago.
The Waverider didn’t reach its Mach 6 goal, nor is it tied directly to any new weapon or aircraft. But it’s the kind of research and development effort that has historically underpinned the U.S. military’s technological edge. More, please.