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Will a New Hypersonic Aircraft Really Let Us Fly from New York to London in an Hour?
By Daniel Lametti
Aug. 14, 2012
There’s nothing worse than a long flight. Perhaps that’s why the Internet was filled this morning with reports that the United States Air Force was testing an experimental plane that could, in theory, fly from New York to London in about an hour. (According to the Washington Post, the test flight did indeed take place Tuesday, but there’s been no word yet on the results.)
The X-51A Waverider uses a special scramjet engine to propel it to five times the speed of sound—that’s hypersonic speed, or more than 3500 miles per hour. Scramjet stands for supersonic combustion ramjet. Simply put, rapidly moving air is funneled into an engine, mixed with fuel, and ignited to produce thrust. (A conventional jet engine needs the help of heavy compressors and turbines to achieve the same result.) In a ramjet, the air inside the engine is typical moving at subsonic speeds when it’s ignited; in a scramjet, the air inside the engine is lit at supersonic speeds. This makes scramjets more efficient while increasing thrust.
Full article here.
