Six engines, Mach 3 speed, nuclear capability—the XB-70 Valkyrie was meant to dominate the skies. But it became one of the Cold War’s biggest "what ifs." This is its story. 20 Beautiful Baby ...

XB-70’s design was a marvel of engineering ... The Valkyrie was powered by six General Electric YJ93 afterburning turbojet engines, producing a combined thrust of 180,000 pounds.