The aim is to fly at about Mach 2, twice the speed of sound.

目标是以大约2马赫的速度飞行，也就是音速的两倍。

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An experimental investigation on effects of oscillating shock generated by liquid jet on reinforcement of hydrogen-fueled supersonic combustion in Mach 2 airstream was completed.

研究了在燃烧室入口马赫数为2的超音速燃烧中，液体射流所产生的振荡激波对强化超音速燃烧的作用。

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A.L.L.S. flew all the way from Switzerland to launch a 10-foot, carbon-fiber beauty designed to go Mach 2.5.

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By contrast, a jet fighter plane travels at speeds of Mach 1 to Mach 2, and the Space Shuttle blasts into space at Mach 25.

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At altitude, its top speed is Mach 2.25 compared to Mach 2 for the U.S. F-16 Fighting Falcon, another multirole fighter aircraft made by General Dynamics and Lockheed Martin.

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