Chuck Yeager's 1947 supersonic flight remembered

On Oct. 14, 1947, U.S. Air Force test pilot Chuck Yeager became the first person to fly faster than sound in level flight, piloting the Bell X-1 rocket plane. Dropped from a B-29 bomber, the aircraft reached Mach 1.07, roughly 821 mph, after Yeager had injured his ribs in a horse-riding accident the previous night. The flight demonstrated that piloted supersonic travel was possible and helped open a new era of X-plane testing.

The Bell X-1, initially designated XS-1, came from a joint effort by NACA and the U.S. Army, with Bell Aircraft winning the build contract in March 1945 and delivering the craft that December. It was a single-seat rocket plane, roughly 30 feet long with a 28-foot wingspan, burning liquid oxygen and an ethyl alcohol-water mix. Before Yeager’s powered record run, the program included unpowered glides and progressively faster subsonic flights.

Yeager’s achievement was initially classified. Officials marked the flight and its data secret within two hours; news emerged in December 1947, and the Air Force confirmed it publicly in March 1948. The X-1 effort helped establish research aircraft built for experimentation rather than military or commercial requirements.

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