US military to test ‘Waverider’ Hypersonic jet on Mach 6
The US military has conducted a test flight of its hypersonic jet Waverider, aiming to reach Mach 6 (4,300mph; 6,900km/h) above the Pacific Ocean.
At that speed it could travel from London to New York in about an hour.
Results from the test flight are expected later on Wednesday.
The Pentagon and NASA hope to use the project to develop faster missiles.
During a test in June 2011, Waverider travelled at Mach 5, but failed to reach the target speed.
It is one of several projects currently under way to create a hypersonic aircraft.
The research could also be used to build a commercial plane, able to reach much higher speeds than today's jets, after Concorde was decommissioned in 2003.