NASA X-43A rockets to Mach 9.8 at Edwards

  • Published
  • By Maj. Nori La Rue
  • Air Force Flight Test Center Public Affairs
After postponing the mission because of a problem with the X-43A hypersonic research aircraft, NASA officials said they could not have hoped for a better flight than the one they had here Nov. 16.

"It was a great mission," said Joel Sitz, X-43A project manager. "It was 90 seconds of terror, but once it's over with, you realize you really accomplished some great things."

The mission was intended to flight-validate the operation of the X-43A's supersonic-combustion ramjet -- or scramjet -- engine at a record airspeed of almost 10 times the speed of sound, or about 7,000 mph, according to a NASA press release.

The flight was part of the Hyper-X program, a research effort designed to demonstrate air-breathing propulsion technologies for access to space and high-speed flight within the atmosphere. It will provide unique in-flight data on hypersonic air-breathing engine technologies that have large potential payoffs.

Although officials had not yet had a chance to review much of the telemetric data they collected during the mission, they offered some approximations during a press conference.

At the height of the apex, the Pegasus booster rocket was traveling about Mach 9.8. The estimated max engine test speed was Mach 9.6 or roughly 6,600 mph. The last scramjet flight reached Mach 7 on March 27.

"We had 10 seconds’ fuel on time and 20 seconds of total engine test time data, which dwarfs the amount of data we have been able to collect from all (previous) Mach 10 tests combined," said Randy Voland Sr., lead propulsion engineer from the Langley Research Center in Virginia. "Mach 10 is very hard to test on the ground, and there are very few places you can get any data at Mach 10 with operating engines. So, what we get in a ground test is just a few milliseconds at a time," he said.

Overall, this flight was anything but nominal, said Laurie Marshall, chief engineer for the X-43A project.

"It was a phenomenal flight and really looked a lot like all of the nominal training sessions we've done," she said. "Everything going out to the launch point was pretty good. The drop was nominal (meaning normal), and we had a great boost. We had our engine experiment, and everything looked very nominal to me. We actually had data from the ground-based assets longer than we had predicted. We thought we would lose data from them about 240 seconds into the mission, and we actually ... got a lot of good data."

Part of the reason National Aeronautics and Space Administration officials said they gathered so much information was because a Navy P-3 Orion aircraft provided long-range video support just before the launch and up to 14 minutes thereafter until splash down of the research vehicle.

The real workhorse for the mission, however, was the B-52B, which carried the Pegasus booster and the X-43A out over the Pacific Ocean. The plane had a total takeoff weight of 321,000 pounds, with a stack weight of 37,271 pounds. The "stack" refers to the booster, the X-43A aircraft and the rocket's fuel load of about 30,000 pounds, which burned off in about 90 seconds.

The aircraft has been a part of flight test and research since 1955. It is scheduled to retire from the Air Force inventory in January.

"I think (the aircraft) can lay claim to being the aircraft that has seen -- and actually participated in -- more aviation history than any other single aircraft, ever," said Brig. Gen. Curtis Bedke, Air Force Flight Test Center commander.

So, what does the future hold for this type of technology?

"I think there is definitely a use for this technology aboard commercial aircraft someday," Mr. Sitz said. "It will take some time, but I think we are capable of getting there. I would like to see us focus on combining turbo and scramjet technologies so the aircraft would be able to take off under its own power." (Some information courtesy of Dryden Flight Research Center)