Boeing, Lockheed Martin and Gulfstream – with a bit of assistance from NASA – are working towards the first supersonic commercial passenger airliner.

The ultimate aim is a London-to-Sydney flight that travels in excess of 4000 km/h and takes only four hours.

The companies claim they are close to overcoming the ‘sonic boom’, which rolls in the jet’s wake and was Concorde’s biggest obstacle.

The new jet, codenamed X-54, wouldn’t fly until after 2020, which means a full-sized version could be available by 2030, assuming the new technology was reliable and successful.

The sonic boom was the major factor that prevented Concorde from ever being developed beyond an expensive experimental aircraft. It flew for the last time in November 2003.