August 11, 2011

Test Flight For Mach 20 Aircraft Fails

A test flight for an experimental aircraft failed over the Pacific Ocean on Thursday morning.

The aircraft, known as the Falcon Hypersonic Technology Vehicle 2, was launched at 7:45 a.m. from Vandenberg Air Force Base.

The agency reported engineers "lost telemetry" with the aircraft at 8:22 a.m.

The flight was the aircraft's second and final planned test flight.  The first attempt was on April 22, 2010.

The aircraft  is designed to separate from the booster, dive back toward Earth, level out and glide above the Pacific Ocean at 20 times the speed of sound -- Mach 20.

The plan is for the aircraft to stay in flight for about half an hour before splashing down in the waters near Kwajalein Atoll and sink to the bottom of the ocean, about 4,000 miles west of Vandenberg.

"Downrange assets did not reacquire tracking or telemetry," said the Defense Advanced Research Projects Agency on its Twitter feed. "HTV2 has an autonomous flight termination capability,"

Sustaining speeds in excess of Mach 5 has been extremely difficult for scientists and aeronautical engineers to perfect over the past 5 years. A test flight of the US Air Force's experimental X51 WaveRider aircraft ended prematurely after a lapse in airflow to the engine caused it to shutdown.

The HTV-2 aircraft is outfitted with numerous sensors to provide loads of data on the test flight. More than 20 test assets will collect continuous flight data for the duration of the test. If everything goes according to plan, the aircraft should have spent about 30 minutes in flight.

Read more on DARPA's Falcon Project at