The Falcon Hypersonic Technology Vehicle-2 was launched Thursday from Vandenberg Air Force Base, Calif., and was supposed to separate from the booster at an altitude of several hundred thousand feet and then autonomously glide at 13,000 mph to a splashdown in a sea range near Kwajalein Atoll, 2,500 miles southwest of Hawaii.
The separation did occur, according to a Defense Advanced Research Projects Agency statement.
A preliminary review indicates the vehicle achieved controlled flight in the atmosphere before telemetry was lost, DARPA spokeswoman Johanna Spangenberg Jones said Monday in an e-mail to The Associated Press.
The loss of signal came nine minutes after liftoff.
Flight telemetry from the Air Force, Navy, Army and U.S. Missile Defense Agency was being analyzed to determine details of what happened, including where it came down.
The flight was intended to test technologies for flight at extremely high speeds. The Lockheed Martin-designed HTV-2 was not intended to be recovered. The test would have ended with it reaching its target in 30 minutes, crashing into the sea and sinking.
Thursday's mission was the first of two planned in the HTV-2 program, which uses Minotaur 4 boosters developed by Orbital Sciences Corp. from decommissioned Peacekeeper intercontinental ballistic missiles.
The U.S. military is trying to develop technology to respond to threats around the globe at speeds of Mach 20 or greater, according to DARPA.