The US space agency has finally given green signal for preliminary design of a “low-boom” supersonic passenger jet that will take people places with an unimaginable speed. This is the first in a series of “X-planes” in NASA’s New Aviation Horizons initiative, introduced in the agency’s fiscal year 2017 budget.

NASA has awarded a $20 million contract to Lockheed Martin to develop a preliminary design for a quiet demonstration passenger aircraft designed to fly faster than the speed of sound. The piloted test aircraft would use so-called Quiet Supersonic Technology, or QueSST, to create a supersonic “heartbeat,” a kind of soft thump instead of the annoying sonic booms usually associated with supersonic planes.

Lockheed Martin will develop baseline aircraft requirements and a preliminary aircraft design, with specifications, and provide supporting documentation for concept formulation and planning.

Supersonic commercial passenger airline travel ended when the British Airways and Air France Concordes stopped flying in 2003. The planes had struggled to make profits in the wake of a crash in Paris in 2000 that killed 113 people. The planes used a lot of fuel, required special parts and were high maintenance. The noise from the Concordes created an entire set of restrictions anywhere it flew, except over the ocean.