Washington, Jun 28 (IANS): In a major step towards building an actual X-plane, NASA has completed the preliminary design review of its Quiet Supersonic Transport or QueSST aircraft design.

QueSST is the initial design stage of the agency's planned Low Boom Flight Demonstration (LBFD) experimental airplane, otherwise known as an X-plane, NASA said in a statement on Tuesday.

Senior experts and engineers from across the agency and the Lockheed Martin Corporation concluded that the QueSST design is capable of fulfilling the LBFD aircraft's mission objectives, which are to fly at supersonic speeds, but create a soft "thump" instead of the disruptive sonic boom associated with supersonic flight today.

"Managing a project like this is all about moving from one milestone to the next," said David Richwine, Manager, NASA's Commercial Supersonic Technology Project.

"Our strong partnership with Lockheed Martin helped get us to this point. We're now one step closer to building an actual X-plane," Richwine added.

Flight testing of an LBFD X-plane could begin as early as 2021, NASA said.

The LBFD X-plane will be flown over communities to collect data necessary for regulators to enable supersonic flight over land in the US and elsewhere in the world.

NASA partnered with lead contractor Lockheed Martin in February 2016 for the QueSST preliminary design.

After the success of completing the preliminary design review of the QueSST aircraft design, NASA's project team would start the process of soliciting proposals later this year and awarding a contract early next year to build the piloted, single-engine X-plane.

The acquisition for the LBFD X-plane contract will be fully open and competitive, with the QueSST preliminary design data being made available to qualified bidders, the statement added.