Jet hits 6 times speed of sound

AN UNMANNED X-51A Waverider aircraft has set a record by flying for more than three minutes at six times the speed of sound – the longest supersonic combustion ramjet-powered flight in history.

The experimental aircraft was released from a US Air Force B-52 off the Californian coast yesterday. Its scramjet engine accelerated it to a height of 70,000ft where it reached Mach 6, and it flew under its own power for 200 seconds before losing thrust.

A US Air Force spokesman said: "We are ecstatic to have accomplished many of the X-51A test points during its first hypersonic mission."