In May of 2013, the Air Force successfully tested the X-51 WaveRider — an uncrewed, hypersonic "scramjet" capable of reaching Mach 5.1, or more than five times the speed of sound — by flying it at hypersonic speeds over the Pacific Ocean. Now, the Air Force is looking ahead to its next aircraft.
Air Force Chief Scientist Mica Endsley told Military.com this week that the agency is working on the next generation of its hypersonic vehicle. While the X-51 was a test designed to show that a scramjet craft was feasible, the Air Force now wants a vehicle that can "operate at the kind of temperatures you have when you are going at hypersonic speeds," and plans on building a guidance system that can also work at extreme speeds. The goal is to produce the new craft by 2023.
That is, of course, a long while away, and the US military has had some trouble with hypersonic defense technology. The X-51 was only successful after a string of high-profile failures, and last year, a hypersonic missile being tested by Department of Defense exploded during takeoff.