Image above: Scramjet burns fuel in a stream of supersonic air compressed by the forward speed of the aircraft. Conventional jet engines draw in air and burn it with fuel so it expands in a combustion chamber. The hot air is then forced out the exhaust nozzle to produce thrust. . Credit: NASA’s Dryden Flight Research Center
Image above: The X-43A and its booster will separate from the B-52 at 40,000 feet. It will ascend to 95,000 feet and release from the booster. The scramjet engine will then ignite and, following a free flight, it will land in the ocean. . Credit: NASA’s Dryden Flight Research Center