Press Release

Air Force Microsatellite Launch System Earns Patent

By SpaceRef Editor
August 13, 2001
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KIRTLAND AIR FORCE BASE, N.M. — A modular cargo aircraft pneumatic launch
tube to deploy reusable launch vehicles into low-Earth-orbit may be the
future of a new generation of launch systems, according to researchers here
at the Air Force Research Laboratory’s Space Vehicles Directorate.

“What’s innovative about our newly-patented launch concept, said Ken Hampsten,
AFRL’s launch tube inventor, “is that it can add a unique space launch
capability to existing military cargo aircraft. This could possibly avoid
costly development of specially modified carrier launch aircraft and
expensive construction of new runways, launch pads, and vehicle processing
facilities. The modular launch tube could be designed to reconfigure the
aircraft from space launch to normal cargo modes in less than a day.

“Virtually all aircraft and ground support systems are already in place to
support this innovative rapid launch concept. It could be a quick and cheap
way to send supplies up to the International Space Station,” he said.

Microsatellites are a concept the Air Force Research Laboratory is
investigating for implementation in the future. Microsatellites are
categorized as weighing less than 100 Kg (about 220 pounds) and can
operate individually or be in clustered formations or constellations.
Many microsatellite concepts range between 40 to over 200 microsats in
low-Earth-orbit, unlike today’s large single satellites flying alone. To
make them effective and efficient, microsatellites will need to be launched
in a series of low-cost, high-flight-rate missions. As a result, the lab
has been exploring launch concepts capable of low flight cost, high
reliability, and quick ground turn-around times. “And the launch tube method
is specifically designed to fit that bill,” said Hampsten.

Simply, a small expendable or reusable launch vehicle, possibly the two-stage
reusable spaceplane depicted above, would be ejected using the pneumatic tube
integrated into the inside of the cargo bay of a C-141B, C-5A, or C-17A
aircraft, using modified cargo doors. With the aircraft flying at 35,000-
40,000 feet around 530 miles per hour, the tube would expel the vehicle out
of the back of the aircraft over the ocean. By combining the airborne launch
tube with the unique design features of the spaceplane shown above, the
overall system could lower the vehicle’s propulsion system orbital velocity
requirements by up to ten percent. Basically, this would be accomplished
through a head start in altitude and speed, implementing a first-stage
vacuum nozzle and advanced variable geometry wing technology, said Hampsten.
The upper stage, equipped with a much smaller version of a payload bay
similar to the Space Shuttle, would take the satellite to orbit, deploy it,
and return to earth, possibly using a parafoil technique for ground landing,
similar to NASA’s flight tested X-38 reentry lifting body/parafoil
experimental recovery vehicles. After separation, the booster is designed
to glide back to land for recovery as well.

Hampsten leads AFRL’s Space Vehicles Directorate’s Advanced Space
Transportation Branch at Kirtland Air Force Base and is responsible for
flight-testing innovative launch systems as well as creating and evaluating
concepts that can improve the responsiveness and lower the cost of getting
payloads safely into space.

[NOTE: An image supporting this release is available at
http://www.vs.afrl.af.mil/News/01-10.html]

SpaceRef staff editor.