The Supersonic unmanned aircraft teared through the atmosphere at 20 times the speed of sound.
DARPA, the Defense Advanced Research Project Agency, has made public its best guess about what might have caused its unmanned arrowhead-shaped Hypersonic Technology Vehicle (HTV-2) skin to suddenly came off, the craft lost contact with the controls and crash in the Pacific just a few minutes after racing at neck breaking speed at Mach 20.
During the eight-month review, DARPA concluded that even though the HTV-2 expected it to lose some of its skin mid-flight, "larger than anticipated portions of the vehicle's skin peeled from the aerostructure," the agency said in a statement Friday.
The agency confirmed that the shocks it experienced last August were "more than 100 times what the vehicle was designed to withstand."
While the test was very public, the details of the HTV-2's design, stability system and potential purpose remain top secret.
Two months after DARPA's test, the Army tested its own hypersonic aircraft - this one a long-range weapon system called the Advanced Hypersonic Weapon (AHW) designed to strike any target in the world in just a couple hours.
