Here’s what the Pentagon’s technological innovators hope will happen today: They’ll take an unmanned aircraft, launch it from an Air Force base in California and, once high in the atmosphere, have it barrel through the sky at about 13,000 miles per hour — a flight speed that would have it rocket from New York to Los Angeles in about 12 minutes.

That’s the hope, anyway.

It’s all part of the Defense Advanced Research Projects Agency’s second test of an aircraft known as the Falcon Hypersonic Technology Vehicle 2.

The ultimate goal is to develop a technology that would allow the U.S. military to respond to threats anywhere in the world within an hour — a capability that U.S. officials have said is necessary to deter against terrorist networks and other adversaries.

Whether today’s test will go as planned is far from certain. When DARPA tested its hypersonic aircraft for the first time in April 2010, they lost contact with it after about nine minutes — dealing a blow, as Noah Shachtman notes over at Wired’s Danger Room, to the Pentagon’s broader efforts at eliminating enemies anywhere around the world. (The military is also trying to develop missiles armed with conventional warheads that could achieve that goal.)

The launch had initially been scheduled for Wednesday but was postponed.

DARPA says surface temperatures on the Falcon are expected to reach in excess of 3,500 degrees Fahrenheit, hot enough to melt steel. It is supposed to fly 22 times faster than a commercial airliner.