So Far, So Good

DARPA’s Falcon Hypersonic Test Vehicle-2 launched from Vandenberg AFB, Calif., aboard a Minotaur IV rocket early morning on Aug. 11. It was second launch attempt for HTV-2, the first failed to complete its 30-minute glide over the Pacific Ocean due to “higher-than-predicted yaw, which coupled into roll,” according to the conclusions of an independent review panel. However, the vehicle still managed to collect nine minutes of “unique flight data, including 139 seconds of Mach 22 to Mach 17 aerodynamic data,” according to a factsheet on DARPA’s website. HTV-2 is an unmanned, maneuverable aircraft that glides through the Earth’s atmosphere at an astounding Mach 20—the equivalent of flying from New York City to Los Angeles in less than 12 minutes. The vehicle design and trajectory for flight were optimized based on lessons learned in the first flight. “The goal of the second flight is to validate current assumptions and increase technical understanding of the hypersonic flight regime,” according to the factsheet.