North American X-15
Overview π· Photo: NASA On October 3, 1967, William βPeteβ Knight flew the rocket-powered X-15A-2 to Mach 6.7 (4,520 mph, […]
United States
The largest collection in this encyclopedia: from the Bell X-1 that first broke the sound barrier to the SR-71, the F-22 and the B-21 Raider β every generation of American speed.
Bell X-1
Overview π· Photo: NASA The Bell X-1 was the first crewed aircraft to exceed the speed of sound in level