NASA CITES MODELING INACCURACIES IN X-43 CRASH FIN ACTUATOR SYSTEM PROBLEMS ALSO LED TO VEHICLE'S DESTRUCTION.Byline: Jim Skeen Staff Writer EDWARDS AIR FORCE BASE Edwards Air Force Base, U.S. military installation, 301,000 acres (121,805 hectares), S Calif., NE of Lancaster; est. 1933. It is one of the largest air force bases in the United States and has the world's longest runway. - No single factor caused the loss of the hypersonic hy·per·son·ic adj. Of, relating to, or capable of speed equal to or exceeding five times the speed of sound. hy X-43A research vehicle, which went out of control seconds after its June 2001 launch and had to be destroyed by mission controllers, a NASA NASA: see National Aeronautics and Space Administration. NASA in full National Aeronautics and Space Administration Independent U.S. report has concluded. The incident was blamed on several factors, including modeling inaccuracies of the aerodynamics and in the fin actuator system, according to a National Aeronautics and Space Administration National Aeronautics and Space Administration (NASA), civilian agency of the U.S. federal government with the mission of conducting research and developing operational programs in the areas of space exploration, artificial satellites (see satellite, artificial), report released Wednesday. ``The mishap occurred because the control system could not maintain the vehicle stability during transonic transonic in ultrasonography, the complete transmission of sound so the image appears black; anechoic; echolucent. flight,'' said the report by the NASA mishap investigation board. Wedge-shape, only 12 feet long and controlled by computers, the X-43 is more of a jet-powered missile than an airplane. It is part of a $185 million project to flight-test an experimental, extremely high-speed engine called a scramjet scramjet: see jet propulsion. . The ultimate goal is to create a scramjet-powered aircraft, one that would use air from the atmosphere, rather than carry oxygen as a rocket does. A scramjet is a high-altitude, very-high-speed version of a ramjet ramjet: see jet propulsion. ramjet Air-breathing jet engine that operates with no major moving parts. It relies on the craft's forward motion to draw in air and on a specially shaped intake passage to compress the air for combustion. , an engine without traditional jets' whirling fan blades for compressing air to oxidize oxidize /ox·i·dize/ (ok´si-diz) to cause to combine with oxygen or to remove hydrogen. ox·i·dize v. 1. To combine with oxygen; change into an oxide. 2. fuel. By not having to carry oxygen, a spacecraft could save fuel weight and carry more equipment. Since the mishap, changes have been made in the X-43A. A second launch attempt is scheduled for this fall. ``The findings and recommendations of the board greatly enhance our opportunity for a successful second flight,'' said Victor Lebacqz, acting associate administrator of NASA's Office of Aerospace Technology. The X-43 is NASA's first test program dedicated to hypersonic research since the last X-15 rocket plane flight at Edwards Air Force Base in 1969. The X-15's fastest flight was Mach 6.7, or about 4,520 mph, with W.J. ``Pete'' Knight - now the Antelope Valley's state senator - at the controls. Two 12-foot-long X-43A aircraft remain after the June 2, 2001, incident. The first will hit speeds of more than Mach 5, about 3,500 mph. The second is expected to fly at speeds up to Mach 10, about 7,600 mph. In each case, the scramjets would fire for just a few seconds, but long enough to give researchers a wealth of information. NASA and the Air Force are working on a larger X-43 that would actually use the scramjet engine for up to five minutes. Jim Skeen, (661) 267-5743 james.skeen(at)dailynews.com |
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