¡¡¡¡NASA successfully tests hypersonic jet

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¡¡¡¡Three years after its first test flight ended in an explosion, NASA on March 27 successfully launched an experimental jet that the agency believes reached a recordª²setting speed of about 5,000 mph.

¡¡¡¡The unpiloted Xª²43A made an 11ª²second rocket boosted flight, then went through some twists and turns during a sixª²minute glide before plunging into the Pacific Ocean about 400 miles off the California coast.

¡¡¡¡Flight engineer Lawrence Huebner said preliminary data indicated the needleª²nosed jet reached a maximum speed of slightly over seven times the speed of sound, or about 5,000 mph, after a rocket boosted it to about 3,500 mph. Huebner said it was the first time an ¡°airª²breathing¡± jet had ever traveled so fast. The rocketª²powered Xª²15 reached Mach2 6.7 in 1967.

¡¡¡¡NASA built the Xª²43A under a ¡ç250 million program to develop and test an exotic type of engine called a supersonicª²combustion3 ramjet4, or scramjet. In theory, the airª²breathing engine could propel an airplane to speeds of Mach 7 or faster, enabling aroundª²theª²world flights that would take several hours. The Department of Defense also is working on the technology, which is eyeing for use in bombers that quickly could reach targets anywhere on the globe.

¡¡¡¡A third Xª²43A could fly as early as the fall.