The new hypersonic vehicle, which could take flight by 2023, builds upon research from a 2013 test flight of an experimental hypersonic vehicle, the X-51A Waverider, according to Military.com.

The $300 million X-51A program began in 2004. The program's final test flight occurred May 1, 2013, when the unmanned Waverider reached a top speed of Mach 5.1 (more than five times the speed of sound) in just over six minutes, before it was intentionally crashed into the Pacific Ocean. At the time, U.S. Air Force officials said the flight was the longest-ever for a hypersonic vehicle of its kind. [Flying Saucers to Mind Control: 7 Declassified Military & CIA Secrets]