NASA (www.nasa.gov) has taken another step towards re-introducing supersonic flight with the award earlier this month of a contract for the design, building and testing of a supersonic aircraft that reduces the sonic boom to a ‘gentle thump’.

Lockheed Martin Aeronautics Co — based in Palmdale, California — was selected for the Low-Boom Flight Demonstration contract, which is worth some $247.5 million. Work under the contract began on 2 April and runs to 31 December 2021.

Lockheed Martin will complete the design and build of an experimental aircraft, known as an X-plane, which will cruise at 55,000ft and about 940mph yet create a sound about as loud as a car door closing, instead of a sonic boom.

Once NASA accepts the aircraft from the contractor in late 2021, the agency will perform additional flight tests to prove that the ‘quiet supersonic technology’ works as designed, that the aircraft performance is robust, and that the aircraft is safe to operate.

Beginning in mid-2022, NASA will fly the X-plane over select US cities and collect data about community responses to the flights.