Joseph A. Walker flew the world's first two spaceplane flights in 1963, thereby becoming the United States' seventh astronaut. Walker was a Captain in the United States Air Force, an American World War II pilot, an experimental physicist, a NASA test pilot, and a member of the U.S. Air Force Man In Space Soonest spaceflight program. His two X-15 experimental rocket aircraft flights in 1963 that exceeded the Kármán line – the altitude of 100 kilometers, generally considered to mark the threshold of outer space, qualified him as an astronaut under the rules of the U.S. Air Force and the Fédération Aéronautique Internationale (FAI).
Born Joseph Albert Walker on February 20, 1921 in Washington, Pennsylvania and died on June 8, 1966 in Barstow, California when his F-104N Starfighter chase aircraft collided with a North American XB-70 Valkyrie. He was 45.
(Photo:) Walker's F-104 tumbles in flames following the midair collision with the XB-70 62-0207 on June 8, 1966.