What looked to be a successful second launch of DARPA’s Falcon HTV-2 hypersonic vehicle has potentially taken a turn for the worse if DARPA’s Twitter feed is any indication. After successful launch, separation, contact with handlers on the ground, and entry into glide phase, the last we heard from DARPA via @DARPA_News doesn’t seem to bode well: “Range assets have lost telemetry with #HTV2. More to follow.”

That was almost an hour ago at the time of this posting, and more has not followed. So we don’t know if that translates to a fully successful flight or to some kind of vehicle failure. We’ll update here when we have more info.

HTV-2 was developed with one straightforward objective in mind: travel from anywhere on Earth to anywhere else on Earth in an hour. And with that goal in mind, DARPA has engineered a very fast vehicle. HTV-2 rides to near orbital speeds aboard a Minotaur rocket at which point it separates and enters a powered glide phase as it rides back to Earth at speeds topping Mach 20. That’s roughly 13,000 miles per hour (reportedly it is capable of a top speed approaching 17,000 miles per hour). In other words, fast enough to do New York to L.A. in 12 minutes, or London to Sydney in the aforementioned 60 minutes.