DARPA, Lockheed Martin, and the Air Force fired off a Hypersonic Airbreathing Weapon Concept on Monday, only the second time the U.S. has successfully tested such a weapon…DARPA and the U.S. Air Force successfully test fired a Hypersonic Airbreathing Weapon Concept (HAWC) on Monday. This is the second time this kind of advanced missile has been test fired in America and represents the efforts of its military to compete with China and Russia, the latter of which has promoted its own hypersonic missiles as being “unbeatable” weapons to cow the West.