X-43A DATA EVALUATED FLIGHT SHOWS PROMISE FOR HYPERSONIC ENGINE.

Byline: Jim Skeen Staff Writer

EDWARDS AIR FORCE BASE - NASA officials said Wednesday that they are evaluating what they call a treasure trove of data from the record-setting first X-43A flight and prepping for an even-faster flight in the fall.

The goal for the $230 million program is to advance technologies for a scramjet engine - an ultra-high-speed engine that draws oxygen for combustion from the atmosphere rather than having to carry it like a rocket. By not having to carry oxygen, a spacecraft could save fuel weight and carry more equipment.

``The data clearly shows, and without question, that scramjets work,'' said Griff Corpening, NASA Dryden Flight Research Center's X-43A chief engineer. ``But we did see a couple of areas that differed from what was seen in the wind tunnels, thus reinforcing the need for flight testing.''

The scramjet concept has been the subject of analysis and ground tests for years. The data from the March flight will help NASA researchers validate wind-tunnel tests and other analyses on hypersonic flight.

An initial review of the March 27 flight confirmed that high-fidelity flight data were obtained throughout the mission, from its boost from a Pegasus rocket to splashdown in the Pacific Ocean, NASA officials said.

One area that was different was the air-pressure profiles through the engine. The second difference was that modeling predicted that the X-43A's nose would pitch up slightly during separation from the booster rocket, but instead it pitched down slightly.

The March 27 flight, originating from NASA's Dryden Flight Research Center, began with NASA's B-52B launch aircraft carrying the 12-foot-long X-43A out to the test range over the Pacific Ocean about 50 miles off the California coast. The X-43A was boosted up to its test altitude of about 95,000 feet, where it separated from its modified Pegasus booster and flew freely under its own power.

The March 27 flight hit speeds of about 5,000 mph, the fastest speed ever for a craft powered by a jet engine. The fastest known jet is the SR-71 Blackbird, which flew at speeds of about 2,200 mph.

Researchers at the National Aeronautics and Space Administration are planning to fly the second X-43A at close to 7,000 mph this fall. NASA is hoping to conduct the flight by October, said Keith Henry, spokesman for NASA's Langley Research Center in Virginia, which is conducting the research in a joint effort with the Dryden center.

The first X-43 aircraft had to be blown up in June 2001 over the Pacific Ocean by a self-destruction mechanism when the Pegasus booster rocket carrying it went out of control after its fins came off.

A number of factors apparently contributed to the 2001 failure, including the B-52 dropping the rocket at a 23,000-foot altitude, where the atmosphere is much denser than the 40,000 feet at which Pegasus rockets are launched when they go into space.

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.

Plans for follow-on versions of the X-43A have been canceled by NASA as the result of President George W. Bush's new space initiative to return men to the moon. However, both the Air Force and NASA are planning to continue their hypersonic research.

NASA is in the process of developing a long-term hypersonic research program. The Air Force is interested in ultra-fast aircraft that could reach any spot in the world within a couple of hours.

In addition to the two NASA centers, other participants in the program include ATK GASL in Tullahoma, Tenn., which built both the vehicle and the engine, and Boeing Phantom Works in Huntington Beach, which designed the thermal protection and onboard systems.

The Pegasus booster rocket was built by Orbital Sciences Corp. in Chandler, Ariz.

Jim Skeen, [phone]

james.skeen(at)dailynews.com

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The X-43A experimental craft, mounted on its Pegasus booster rocket, drops from a B-52B over the Pacific on March 27.