NASA has awarded Lockheed Martin Skunk Works a $247.5m contract to design, build and flight test the Low-Boom Flight Demonstrator (LBFD), an experimental plane designed to make supersonic passenger air travel a reality.

Lockheed Martin Skunk Works will build a full-scale experimental aircraft based on a preliminary design developed under NASA's Quiet Supersonic Technology (QueSST) effort. The proposed aircraft, carrying a single pilot, will be 94 feet long with a wingspan of 29.5 feet and have a fully-fueled takeoff weight of 32,300 pounds.

The design research speed of the X-plane at a cruising altitude of 55,000 feet is Mach 1.42, or 940mph. Its top speed will be Mach 1.5, or 990mph. The jet will be propelled by a single General Electric F414 engine, the powerplant used by F/A-18E/F fighters.

The aircraft will be built at the Lockheed Martin Skunk Works facility in Palmdale, California, and is scheduled to conduct its first flight in 2021.

The X-plane will help NASA establish an acceptable commercial supersonic noise standard to overturn current regulations banning commercial supersonic travel over land.

Current regulations, which are based on aircraft speed, ban supersonic flight over land. With the low-boom flights, NASA intends to gather data on how effective the quiet supersonic technology is in terms of public acceptance by flying over a handful of U.S. cities, which have yet to be selected.

The complete set of community response data is targeted for delivery to the FAA and ICAO in 2025 from which they can develop and adopt new rules based on perceived sound levels to allow commercial supersonic flight over land.