Last Updated: Thursday, August 16, 2012, 09:00
An unmanned American experimental aircraft failed in a hypersonic test flight and dropped into the Pacific Ocean, the US Air Force said Wednesday.
Last Updated: Tuesday, August 14, 2012, 00:06
London to New York in one hour? US military is ready to test a radical new hypersonic aircraft that can cover a distance of 4,500 mph within seconds.
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