A pair of technicians position the X-40 in its cradle   prior to being lifted and dropped by an Army Chinook helicopter.

A pair of technicians position the X-40 in its cradle prior to being lifted and dropped by an Army Chinook helicopter.


When completed, the X-37 will be carried into orbit   in the bay of the Space Shuttle.

When completed, the X-37 will be carried into orbit in the bay of the Space Shuttle.


Boeing built the X-40A at its Phantom Works R&D   facility in Seal Beach, Calif.

Boeing built the X-40A at its Phantom Works R&D facility in Seal Beach, Calif.


The Air Force's X-40A has successfully completed its fourth free-flight test at Edwards Air Force Base. An Army Chinook helicopter recently carried the unmanned vehicle to a height of 15,170 ft in a special hoist, then released it. During the 2-min flight, the reusable, unpowered spacecraft reached a speed of 151 ft/sec. During the descent, the craft demonstrated its ability to maneuver side to side and to make a safe landing when released just outside its nominal release altitude of 15,000 ft.

"I am very pleased with the results of this flight test," says John Fuller, Boeing project manager. "It is a significant step in the development of the Space Maneuver Vehicle. We wanted to validate low-speed handling qualities and demonstrate autonomous approach and landing capabilities. We did that today. Our next step will be to demonstrate the vehicle's capabilities both in the atmosphere and space."

The X-40, on loan from the Air Force to NASA, was built by The Boeing Co. at its Phantom Works R&D facility at Seal Beach, Calif. The vehicle's first flight was in August of 1998. The 22-ft long spacecraft has a 12-ft wingspan, and weighs approximately 2,600 lb. The X-40 is an 85% scale version of NASA's X-37.

Technologies proven on the X-40 will be incorporated into the X-37, another interim spacecraft paving the way for the final SMV. The X-37 is currently under construction and is scheduled to begin flight testing next year. Plans are to ferry the X-37 into orbit either onboard the Shuttle or on an expendable launch vehicle. It will travel at up to Mach 25 and spend 21 days in space during testing. One of the main areas of exploration for the X-37 will be in the area of thermal protection. Systems in use today are fragile and maintenance intensive.

The AR-2/3, a high-reliability engine with a legacy back to the 1950s will power the X-37 while in orbit. The fuel, hydrogen peroxide and a grade of kerosene known as JP-8, is less toxic and more compact than current rocket propellants, and more environmentally friendly.

Both the X-40 and X-37 are part of the Air Force Space Maneuver Vehicle (SMV) Program. The program's goal is to field small, unpiloted, powered spacecraft to carry out space missions, including military ones such as tactical reconnaissance and space-object identification and surveillance, as well as satellite deployment and logistic flights. SMV is also designed to reduce the operational costs of working in space. The final SMV spacecraft will have relatively simple maintenance requirements, so it can operate with 72 hr or less between missions or loiter on-station in space for up to one year.