NASA, working in conjunction with Lockheed-Martin, has completed and approved the preliminary design for a quiet supersonic jet known as QueSST. The basic idea is to build a plane whose shockwaves produce a diffuse “sonic thump” instead of the usual boom.
The next step will be the construction of an experimental craft, currently referred to as a Low Boom Flight Demonstration Aircraft, to provide proof of concept for larger planes. NASA says it will start accepting proposals for building the experimental plane later this year, and flight testing could start as early as 2021.
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The big question is what the long-term applications of the technology would be. The shutdown of the Concorde in 2003 was only partly down to noise complaints – it also didn’t make money. But businesses including Aerion and Boom are trying to resuscitate the supersonic business jet, and NASA’s research could eventually help lower regulatory barriers around aircraft noise.