Project Score

On Dec. 18, 1958, the Air Force placed in orbit the first artificial communications satellite, a Project Score relay vehicle integral with the four-ton Atlas launcher. The next day, the satellite broadcast a taped recording of President Dwight D. Eisenhower's Christmas message--the first time a human voice had been heard from space. (U.S. Army illustration)

Navaho X-10

On Dec. 7, 1954, the U.S. Air Force made first successful recovery of the Navaho X-10 vehicle using a fully automated approach and landing system at Edwards Air Force Base, Calif. The X-10 was a supersonic research test vehicle designed to obtain advanced aerodynamic design data to be used in the development of the North American SM-64 Navaho ground-to-ground missile system. (U.S. Air Force photo illustration)

Japanese Balloon Bombs

On Nov. 3, 1944, the Japanese launched operational balloon bombs as a means of direct reprisal against the U.S. mainland as a result of the Doolittle Raid on Tokyo. The balloons, made of paper or rubberized silk, carried anti-personnel and incendiary bombs. (U.S. Air Force illustration)

B-47 Stratojet

An overall view of a Boeing B-47 Stratojet aircraft in flight April 7, 1956. It was the world's first swept-wing bomber. (U.S. Air Force photo)

Capt. Mel Apt

Capt. Mel Apt sits in the Bell X-2 rocket-powered aircraft at Rogers Dry Lake, Calif., near Edwards Air Force Base. He reached a speed of Mach 3.2 -- three times the speed of sound -- in the X-2 before it tumbled out of control and he was killed attempting to bail out Sept. 27, 1956. (U.S. Air Force photo)

XF-92A

The experimental XF-92A was the first true delta-wing aircraft. It was to serve as a flying prototype for a supersonic interceptor. The XF-92 program was cancelled without further production, but its design led to other delta-wing aircraft. (U.S.Air Force photo)