The Hypersonic Test Vehicle 2 (HTV-2) seemed to be flying well after its release from a Minotaur IV booster last April 22nd. The goal was to test the thermal protection system and aerodynamic controls. However, contact was lost unexpectedly 9 minutes into the flight. See posts here and here.
DARPA now believes it understands what happened and will proceed to fly another vehicle: /– DARPA Concludes Review of Falcon HTV-2 Flight Anomaly – DARPA (pdf) /– Darpa: Now We Know Why Our Mach 20 Ship Crashed – Danger Room/Wired.com
> the HTV wobbled too much. Rather than risking an out-of-control flight, the bot self-destructed. On the bright side, according to a chipper Darpa release, the failed test “demonstrated successfully the first ever use of an autonomous flight termination system.”