Mach 7 ‘scramjet’ test successful

LOS ANGELES (AP) — Three years after its first test flight ended in an explosion, NASA yesterday successfully launched an experimental jet designed to reach speeds approaching 5,000 mph.

The unpiloted X-43A made a 10-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.

“Everything worked according to plan. It’s been wonderful,” NASA spokeswoman Leslie Williams said. “I actually thought it was the most beautiful thing I’ve ever seen. We’ve been waiting a few years.”

It wasn’t immediately clear what speed the needle-nosed jet achieved after it was boosted to about 3,500 mph by a rocket, Miss Williams said.

The agency 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.

NASA and the military have pursued scramjet technology because it theoretically could cut the cost of rocket travel. Rockets must carry their own oxygen to combust the fuel they carry, increasing the weight they must lift during launch, but scramjets could scoop it out of the atmosphere.

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 hours. The Defense Department also is working on the technology, which it is eyeing for use in bombers that quickly could reach targets anywhere on the globe.

The 2,800-pound X-43A was mounted on a Pegasus rocket booster and carried to an altitude of 40,000 feet by a modified B-52 bomber, which took off from Edwards Air Force Base in the high desert.

After the craft was dropped, the rocket flared, sending the jet skyward on a streak of flame and light. At about 100,000 feet, the rocket dropped away.

The first X-43A flight ended in failure June 2, 2001, when the modified Pegasus rocket used to accelerate the plane veered off course and had to be destroyed.