sound barrier

The Bell X-1 plane, famed as US test pilot Chuck Yeager's ‘Glamorous Glennis’, was the first plane to break the sound barrier. It is seen here accelerating towards Mach 1 on its epic flight on 14 October 1947. The aircraft's conical nose, modelled on the lines of a .50 calibre bullet, and the shock diamonds from its exhaust trail, can be seen.

Concept that the speed of sound, or sonic speed (about 1,220 kph/760 mph at sea level), constitutes a speed limit to flight through the atmosphere, since a badly designed aircraft suffers severe buffeting at near sonic speed owing to the formation of shock waves. US test pilot Chuck Yeager first flew through the ‘barrier’ in 1947 in a Bell X-1 rocket plane. Now, by careful design, such aircraft as Concorde can fly at supersonic speed with ease, though they create in their wake a sonic boom.