London, United Kingdom, February 5, 2008—An artist's rendering depicts the takeoff of an A2 aircraft, a proposed hypersonic jet unveiled this week by British engineers.

The A2 was designed by U.K.-based Reaction Engines as part of an international effort to develop a passenger vehicle suitable for hypersonic flight, which means flying at least five times the speed of sound.

Cruising at nearly 19 miles (30 kilometers) above the Earth, the A2 could attain speeds of 3,400 miles an hour (5,470 kilometers an hour)—taking travelers from, for example, Belgium to Australia, in four hours and 40 minutes, engineers said.

“It sounds incredible by today's standards, but I don't see why future generations can't make day trips to Australasia,” Alan Bond, the project's senior engineer, told the London Times.

The A2 could be in service in about 25 years, he added.

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