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X-43A launched
NASA's experimental X-43A hypersonic research aircraft is successfully launched by a Pegasus rocket off the coast of California on March 27. (2min 40sec file)
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Longer launch movie
This extended clip shows the launch of X-43A as seen live through completion of the scramjet propulsion test. (3min 11sec file)
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Pre-launch preps
Technicians put the final touches on the X-43A research vehicle just before the B-52 rolled to the runway. (1min 36sec file)
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B-52 taxi
The B-52 carrier aircraft heads for the runway at Edwards Air Force Base in advance of takeoff. (2min 48sec file)
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Carrier jet takes off
With the Pegasus rocket booster and X-43A mounted beneath its right wing, the B-52 carrier aircraft roars into the sky. (1min 40sec file)
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X-43A readiness test
The aerosurfaces on the X-43A research vehicle are tested prior to launch. (26sec file)
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Pegasus fin sweep
The aerosurface fins of the Pegasus rocket booster undergo a movement test one minute before launch. (26sec file)
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B-52 returns to base
Having completed its mission, the B-52 lands safely at Edwards Air Force. (3min 27sec file)
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Post-launch news conference
Mission officials hold a post-launch press briefing to announce results of the X-43A flight on March 27. (30min 05sec file)
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Preview animation
This animation shows a Pegasus rocket booster launching NASA's X-43A experimental air-breathing scramjet vehicle. (QuickTime file)
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Pre-launch news conference
The pre-launch news conference is held at NASA's Dryden Flight Research Center on March 24 to preview this X-43A experimental flight. (41min 50sec file)
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Scramjet experiment soars off California coast
Posted: March 27, 2004

NASA's experimental X-43A hypersonic research vehicle was successfully launched Saturday, demonstrating for the first time an airbreathing scramjet-powered aircraft while soaring 95,000 feet above the Pacific Ocean at seven times the speed of sound.

The Pegasus rocket and X-43A fall away from B-52 carrier jet. Credit: NASA/Jim Ross
"Today was a grand-slam in the bottom of the 12th," said Joel Sitz, X-43A project manager from NASA's Dryden Flight Research Center. "It was fun all the way to Mach 7. We separated the research vehicle from the launch vehicle, as well as separating the real from the imagined."

The experiment was part of NASA's high-risk, $250 million Hyper-X program that seeks alternate propulsion technologies for access to space and high-speed flight within the atmosphere.

A scramjet operates by supersonic combustion of fuel in a stream of air compressed by the high forward speed of the aircraft itself, as opposed to a normal jet engine, in which fan blades compress the air.

In order to test the scramjet, the 12-foot-long, five-foot-wide X-43A vehicle was blasted high above Earth on the end of a solid-fueled Pegasus rocket booster.

The single-stage Pegasus was carried from California's Edwards Air Force Base to a position 50 miles off the Southern California coast by a B-52B aircraft, then dropped at an altitude of 40,000 feet at 2200 GMT (5:00 p.m. EST; 2:00 p.m. PST).

After free-falling for five seconds, the Pegasus ignited for an 80-second firing.

The Pegasus booster fires into the sky with X-43A. Credit: NASA/Jim Ross
Once the rocket motor had burned out, the 2,800-pound X-43A was released to fly on its own and perform its history-making experiment at nearly 5,000 mph.

The supersonic combustion ramjet, or scramjet, operated for about 10 seconds -- the duration of its hydrogen fuel supply.

"It's been a great, record-breaking day," said Larry Huebner, Hyper-X propulsion lead from NASA's Langley Research Center. "We achieved positive acceleration of the vehicle while we were climbing, and maintained outstanding vehicle control. This was a world-record speed for air-breathing flight."

Controllers gathered several additional minutes of data as X-43A glided back to Earth, eventually splashing down in the Pacific approximately 450 miles off the coast about 10 minutes after launch.

The X-43A vehicle and engine were built by ATK GASL, formerly MicroCraft, of Tullahoma, Tennessee. Boeing Phantom Works in Huntington Beach, Calif., designed the thermal protection and onboard systems. The booster is a modified Pegasus rocket built by Orbital Sciences Corp. Chandler, Ariz.

An artist's concept of X-43A mission sequence. Credit: NASA
Researchers believe the Hyper-X technologies may someday offer more airplane-like operations and other benefits compared to traditional rocket systems. Rockets provide limited throttle control and must carry heavy tanks filled with liquid oxygen, necessary for combustion of fuel. An air-breathing engine, like that on the X-43A, scoops oxygen from the air as it flies. The weight savings could be used to increase payload capacity, increase range or reduce vehicle size for the same payload.

The test flight came nearly three years after an initial X-43A launch was destroyed moments after it began when the Pegasus rocket booster veered off course. Investigators reported there was no single contributing factor, but the root cause of the problem was identified as the control system of the booster.

"After several years of detailed analysis, design upgrades and testing to address the factors that contributed to the failure of the program's first flight, it is all the more gratifying to have carried out this successful flight test," said Ron Grabe, executive vice president and general manager of Orbital's Launch Systems Group.

"Our congratulations go out to NASA and all the partners on this program who persevered to get it right. We now have our sights set on a successful third mission to provide even more critical data to NASA's research into the field of hypersonic flight and to extend the flight speed record set today to Mach 10," Grabe added.