On January 19, 1946, the Bell X-1 flew for the first time, launching a research program that would lead to the world's first supersonic flight and the breaking of the sound barrier.

The X-1’s fuselage was designed to resemble a .50 caliber bullet—one of the only shapes known to have stable flight at supersonic speeds. The Bell X-1 hangs today from the ceiling of the National Air ...

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