Star Raker was a NASA project, and designed to fly Mach 6 air breathing to 93,000 feet on ten hydrogen TBCC ramjets before igniting its three RS-25 rocket engines in parallel to 107,000 feet, after which it went full rocket mode. Late ‘70’s Rockwell design. Similar tridelta wing configuration, but definitely not designed for air breathing at Mach 12 and not an Air Force project.