Amazing new concepts for a 'successor' to the Concorde supersonic passenger jet are being developed by a group of companies working with Nasa scientists.
Boeing, Lockheed Martin and Gulfstream are in a race to design and build a craft which can travel from London to Sydney in four hours.
The 'Son of Concorde' plane will be aimed at the business market at first, and will likely not fly until at least 2020.
It will be around four times as fast as the current quickest executive jet - the £40m Gulfstream C650 which can fly 7,000 miles at 647mph.
The big hurdle is the 'sonic boom' which is created when the plane travels faster than the speed of sound.
The boom was one of the principal reasons that the supersonic Concorde was restricted to non-land routes and was retired in 2003 after proving commercially unviable.
Engineers say the boom created by the new plane will be "closer to a puff".
According to a Gulfstream engineer speaking to the Sunday Times, the new plane would fly at more than 4000km/hour and could make the 16,000km journey to Sydney in four hours.
If the tests on the new plane are successful, and customers can be found, the X-54 plane would be commercially available by 2030 at the earliest.
According to the Sunday Times, which reported the story ahead of a likely announcement at the Farnborough air show, where designs for other supersonic commercial jets will also be shown.