Shockwaves Caused Crash of DARPA Hypersonic AircraftShockwaves Caused Crash of DARPA Hypersonic Aircraft

Stronger than expected shockwaves on the outer shell of a hypersonic vehicle designed by the Defense Advanced Research Projects Agency (DARPA) caused it to crash during a test flight last year, an independent engineering review board (ERB) has concluded.

DARPA's Hypersonic Technology Vehicle (HTV-2) successfully flew nearly 13,000mph for about three minutes in its second test flight on August 11 before its safety system sent it crashing into the Pacific Ocean nine minutes into the flight. Shockwaves, 100 times more than the vehicle was designed to withstand, peeled off portions of the aircraft's thermal shell, causing the early flight termination, the ERB said after a seven-month analysis of data collected from the flight.