About $320 million in U.S. taxpayer dollars has gone into two hypersonic aircraft designed and built by a defense research agency -- which launched each experimental vehicle in separate tests and then promptly lost contact with them, as they barreled into the Pacific Ocean.
The latest unmanned Falcon Hypersonic Technology Vehicle-2 -- a test rocket designed to fly at Mach 20, or around 13,000 miles per hour -- successfully launched at approximately 7:45 a.m. PDT Thursday and separated properly from the Minotaur IV rocket that carried it to the edge of space. But after 2,700 seconds of flight, the agency lost contact with the vehicle, which presumably sank in the blue waters of the Pacific Ocean.
In a statement on the mission, Air Force Maj. Chris Schulz, Defense Advanced Research Projects Agency (DARPA) HTV-2 program manager, said the agency had learned from the flight. But he also acknowledged that the mission was shy of perfection.
"It’s vexing; I’m confident there is a solution. We have to find it,” the statement read.
The fate of the test on Thursday is reminiscent of the April 2010 initial test flight, which also ended with the military losing contact with the vehicle after 9 minutes. It too went down in the Pacific.
The military research group began the hypersonic test program began in 2003. It has cost a whopping $320 million, Eric Mazzacone, a DARPA public affairs officer, told FoxNews.com.
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Lt. Gen. Tom McInerey, former U.S. Air Force Vice Chief of Staff, told Fox News that the project is designed to let military strikes occur anywhere within minutes. But superfast weapons may simply be too expensive to be practical, he said.
"It costs about 1 billion dollars if we wanted to field about 10 or 20 of them per target ... and that's just not affordable," he said.
DARPA defended the costly test missions, declaring that valuable information was collected while the aircraft was in flight -- despite the unsuccessful end.
"We know how to boost the aircraft to near space. We know how to insert the aircraft into atmospheric hypersonic flight. We do now know how to achieve the desired control during the aerodynamic phase of flight," Schulz said.
At first, the launch seemed to go off successfully, despite the dense Central Coast fog making it hard to see the glider take-off -- only the sounds of the launch resonated through the air. No light from the "Falcon" craft was visible, all that was seen was a whiteout from fog and green hills in the foreground.
When the aircraft was in flight, the latest status reports were broadcast across the Air Force base from a loudspeaker where attendees watched the launch. Over that Countdown Network, the Range Launch Conductor said that it had lost optical site of the HTV-2 at approximately 8:15 a.m. PDT.
“Range assets have lost telemetry with #HTV2," the agency announced via Twitter shortly after the flight. "Downrange assets did not reacquire tracking or telemetry. #HTV2 has an autonomous flight termination capability. More to follow,” the agency wrote about an hour later.
After 2,700 seconds of flight, the launch ended.
A Vandenberg Air Force Base spokesman called the launch a success nevertheless. McInerney told Fox News the latest incident cast a pall over the program.
"I think that we've seen from what happened today and what happened last April that there are a lot of challenges in front of it."
"It is a marvelous research and development exercise, we've learned a lot about hypersonic speeds, et cetera. But I just don't see the practicality in it," he said.
Michelle Macaluso is part of the Junior Reporter program at Fox News. Get more information on the program here.