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

Is it possible to break the sound barrier quietly?

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

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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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