Edwards, CA —In a dress rehearsal for its upcoming free flight, NASA's X-43A unmanned hypersonic research vehicle and its Pegasus booster had a successful first captive-carry flight on April 28, attached to the wing pylon of a B-52.
The nearly two-hour mission marks NASA's return to dedicated hypersonic (at least five times the speed of sound) research flights for the first time since 1969. The first free flight was scheduled for mid-May, says NASA Dryden spokesperson Leslie Williams.
According to NASA, the X-43A is the first craft to blend an integrated airframe with a supersonic combustion ramjet (scramjet) engine, designed to make it the first air-breathing hypersonic research vessel. The vehicle raises hopes of significant weight and volume savings that may enable heavier payloads or longer flights for future operational aircraft.
In the first free flight, NASA expects the booster to accelerate the X-43A to Mach 7 at about 95,000 feet altitude. The second free flight will also fly at Mach 7 and the third at Mach 10. Each craft will fly once off the southern coast of California and impact into the Pacific Ocean.
Fueled by hydrogen, the X-43A has a wingspan of approximately five feet, is 12 feet long, and weighs around 2,800 lbs (See DN 9/6/1999 for more information on the X-43).