NASA Believes Test Jet Hit 5,000-Mph Mark
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By ROBERT JABLON, Associated Press Writer
LOS ANGELES - Three years after its first test flight ended in an explosion, NASA on Saturday successfully launched an experimental jet that the agency believes reached a record-setting speed of about 5,000 mph.
The unpiloted X-43A made an 11-second powered flight, then went through some twists and turns during a six-minute glide before plunging into the Pacific Ocean about 400 miles off the California coast.
"It was fun all the way to Mach 7," said Joel Sitz, project manager at NASA's Dryden Flight Research Center.
Flight engineer Lawrence Huebner said preliminary data indicated the needle-nosed 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 "air-breathing" jet had ever traveled so fast.
The rocket-powered X-15 reached Mach 6.7 in 1967.
"It's a great way to end, certainly all the sweeter because of the challenges we've had to step up to and overcome through the life of this project," said Griffin Corpening, Dryden's chief engineer on the project.
The first X-43A flight ended in failure June 2, 2001, after the modified Pegasus rocket used to accelerate the plane veered off course and was detonated. An investigation board found preflight analyses failed to predict how the rocket would perform, leaving its control system unable to maintain stable flight.
NASA built the X-43A under a $250 million program to develop and test an exotic type of engine called a supersonic-combustion ramjet, or scramjet.
In theory, the air-breathing engine could propel an airplane to speeds of Mach 7 or faster, enabling around-the-world flights that would take several...