The hunt is on for clues as to why Darpa’s second, and final, Hypersonic Test Vehicle (HTV-2) lost contact with range controllers and destroyed itself before completing a planned 30-min Mach 20 gliding flight across the Pacific earlier today.
Darpa was doing a good job of keeping everyone informed on the progress of the test using Twitter until the appearance of the ominous words “Range assets have lost telemetry with HTV-2. More to follow.” A while later the site said simply “Downrange assets did not reacquire tracking or telemetry. HTV-2 has an autonomous flight termination capability.”
HTV-2b lifts off through the thick mist and drizzle at Vandenberg AFB. (Bill Hartenstein)
Prior to this, the vehicle had been deployed successfully into its glide phase by an Orbital Minotaur IV Lite launcher which separated from HTV-2b at around Mach 20.
In its first statement on the loss, Darpa says, "the Minotaur IV vehicle successfully inserted the aircraft into the desired trajectory. Separation of the vehicle was confirmed by rocket cam and the aircraft transitioned to Mach 20 aerodynamic flight. This transition represents a critical knowledge and control point in maneuvering atmospheric hypersonic flight. More than nine minutes of data was collected before an anomaly caused loss of signal. Initial indications are that the aircraft impacted the Pacific Ocean along the planned flight path.”
Darpa HTV-2 program manager Air Force Maj. Chris Schulz says “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.”
An independent engineering review board is being set up to review and analyze data from the August 11 flight. “This data will inform policy, acquisition and operational decisions for future Conventional Prompt Global Strike programs—the goal of which, ultimately, is to have the capability to reach anywhere in the world in less than one hour,” says Darpa.
Click here to see a video simulation of what HTV-2b had planned to do during the flight.