The Defense Advanced Research Projects Agency (DARPA) flew the fastest aircraft ever built – until it disappeared. The Falcon Hypersonic Technology Vehicle 2 (HTV-2) was launched aboard a rocket at 7:45 am Thursday, August 11 from Vandenberg Air Force Base in California. Designed to reach any point on the planet in under an hour, the launch was the second test of the HTV-2 system. Following separation from a Minotaur IV rocket, the HTV-2 began flying at Mach 20. Shortly thereafter, contact was lost.

“Here’s what we know,” said Air Force Maj. Chris Schulz, DARPA HTV-2 program manager and PhD in aerospace engineering in an agency news release. “We know how to boost the aircraft to near space.  We know how to insert the aircraft into atmospheric hypersonic flight.  We do not yet know how to achieve the desired control during the aerodynamic phase of flight.  It’s vexing; I’m confident there is a solution. We have to find it.” 

The first test of the HTV-2, conducted in April 2010, yielded similar results. DARPA officials said despite the loss of the aircraft, they collected valuable data and will attempt another test in the future.

“Filling the gaps in our understanding of hypersonic flight in this demanding regime requires that we be willing to fly,” said DARPA Director Regina Dugan. “In the April 2010 test, we obtained four times the amount of data previously available at these speeds.  Today more than 20 air, land, sea and space data collection systems were operational.  We’ll learn. We’ll try again. That’s what it takes.”

The video below shows how the test was supposed to have gone (no audio).