Amazing.How Stuff Works wrote:NASA's experimental space plane, the X-43A, set a new speed record for aircraft on November 16, 2004. In the unmanned test flight, the plane reached Mach 10 -- 10 times the speed of sound, or about 6,600 miles (10,600 kilometers) per hour. This flight broke the previous speed record of Mach 7, set in March 2004 by the X-43A in a previous test flight.
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