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Is it possible to break the sound barrier quietly? © Getty Images

Is it possible to break the sound barrier quietly?

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When you break the sound barrier it generates shockwaves but is there any way to take the boom out of these sonic booms?

Asked by: Anonymous


As an aircraft moves through the air, it sets up waves of compressed air – ‘pressure waves’ – around its fuselage, like the bow wave of a boat. At the speed of sound, the aircraft is traveling so fast that the waves of compression merge into a shock wave, producing a change in air pressure so rapid that it sounds like an explosion.

This ‘sonic boom’ has always been the bane of commercial supersonic aircraft design: Concorde was forced to remain subsonic except over the open sea, significantly reducing its average speed, and thus its commercial advantage.

In principle, it’s possible to reduce the build-up of the pressure waves through careful design of wings and fuselage. Engineers at Lockheed in California have been working on a 12-passenger aircraft called the Quiet Supersonic Transport (above) whose sleek gull-wing and rear-engined design is aimed at reducing the noise of the sonic boom tenfold.


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Robert is a science writer and visiting professor of science at Aston University.


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