World's fastest plane gets test flight today

Even with the world's most powerful computers, there's only so much the brains of the U.S. military can learn about flying at 20 times the speed of sound — 13,000 mph — outside of a real test. That happens today, when the Falcon HTV-2 launches. UPDATE: Anyone seen a hot arrow-shaped plane?

Designed by the Defense Advanced Research Projects Agency, the rocket-launched Falcon HTV-2 in theory could carry a payload to any target on Earth in under an hour. In practice, DARPA still has to answer many questions, like what happens to the craft's skin under 3,400-degree Fahrenheit cruising temperatures, and why did the previous test end with a "flight anomaly" that triggered the craft's self-protection measures to send it plunging into the ocean.

After launching from Vandenberg AFB, Calif., aboard an Air Force Minotaur IV rocket sometime this morning, the Falcon HTV-2 will hit speeds of 13,000 mph — enough to travel from New York to Los Angeles in 12 minutes. If all goes to plan, sensors on board and earth-bound monitors will watch the Falcon's maneuvers for a 30-minute flight before another ocean landing. If its successful, the world may become a slightly smaller place.

UPDATE: Well, that's not good. DARPA reports that as it entered its glide path, the tracking systems lost contact with the HTV-2, and the downrange sensors didn't find it, either. There's either an expensive piece of equipment floating somewhere in the Pacific, or the Falcon has joined the heavens permanently.