Imagine an aircraft that can fly at rocket speeds, seven times the speed of sound. NASA engineers are preparing for the first in a series of test flights that will turn imagination into reality with the X-43A and its hypersonic engine.

Artist's concept of X-43A with Pegasus rocket on B-52. Photo: NASA

The first of three scheduled test flights of NASA's scramjet- propelled aircraft is scheduled for Saturday, June 2. A second flight is scheduled for this winter and a final X-43A flight is set for late next year.

Typical of any "X," or experimental program, X-43A will fly only when weather conditions and all technical factors point to the best chance of success.

The X-43A, 12-feet long with a 5-foot wingspan, will be dropped from a B-52 bomber flying from NASA's Dryden Flight Research Center, Edwards, CA. After being boosted by a Pegasus rocket, the X43A will fly at speeds approaching Mach 7 before splashing into the Pacific Ocean.

As of Friday, no technical issues are being worked and weather permitting, NASA's B-52 launch aircraft carrying the X-43A and its Pegasus booster rocket will take off from Edwards Air Force Base at about 3 p.m. EDT Saturday.

Launch of the booster and X-43A stack is set for about 4:30 p.m. EDT. The booster will propel the X-43A to speeds of about Mach 7 and an altitude of 95,000 feet. At that point, the X-43A will separate from the rocket booster and continue briefly at about Mach 7 -- or seven times the speed of sound -- powered by its revolutionary supersonic-combustion ramjet engine before descending for spashdown in the Pacific Ocean some 10 minutes later.

Pre-flight Testing of the X-43A was successfully completed on Thursday, and all data looked good. The launch vehicle, including the modified Pegasus booster rocket, is now is ready for day-of-flight and flight operations.

The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mother ship, had a successful first captive-carry flight on April 18, 2001. A dress rehearsal for the subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden.

If the first flight occurs Saturday, June 2, a press conference will be held a couple of hours after the B-52 carrier aircraft returns to base. NASA Television will carry the news conference and will air video replays of the X-43A flight.

Two-way question and answer capability will be available at both Dryden and NASA's Langley Research Center, Hampton, VA.

NASA TV is broadcast on GE-2, transponder 9C, C-Band, located at 85 degrees West longitude, frequency 3880 MHz. Polarization is vertical and audio is monaural at 6.8 MHz.

Regularly updated status reports on the flight of X-43A will be available by calling Dryden at 661/276-2564.