NASA has selected Lockheed Martin to build an X-plane to show sonic booms can be reduced to a level low enough to justify lifting the ban on civil supersonic flight over land.

The Low Boom Flight Demonstrator is scheduled to fly in 2021 and will be used to gather community-response data to enable the FAA and International Civil Aviation Organization (ICAO) to develop sound-based rules for supersonic flight.

Lockheed’s Skunk Works had produced a preliminary design for the demonstrator under a previous contract from NASA and was the sole bidder to build the X-plane, says Ed Waggoner, director of NASA’s Integrated Aviation Systems Program. Under the $247.5 million contract, Lockheed will complete design and fabrication of the single-seat, single-engine demonstrator, which is expected to receive its X-plane designation this summer.

The aircraft is shaped to reduce sonic boom and designed to mimic the shockwave signature of a quiet supersonic airliner, generating a maximum boom loudness of 75 PLdB flying at Mach 1.4 and 55,000 ft. This compares with 105-110 PLdB for the Concorde.

NASA believes the low-boom demonstrator will pave the way for development of quiet supersonic transports by U.S. industry once the overland flight ban has been lifted and replaced by sound-based certification rules.