Here's some information on a TSTO (not including the towing aircraft) Astroliner. Taken from the
FAA 2001 RLV report:
[quote author=FAA 2001 RLV report]
Slowed development of the NGSO satellite market has prompted a change in Kelly Space and Technology efforts to develop space transportation capabilities. Last year, Kelly planned to design and develop the Astroliner vehicle for launch in 2002. The company is now focused on development of “Second Generation” RLV capabilities that will serve sub-orbital, NGSO, geostationary orbit and ISS customers.
Kelly’s piloted Second Generation RLV system will be based on its patented horizontal takeoff and landing, tow-launch technique and is designed to carry humans and cargoes to and from destinations off the Earth. The two-stage-to-orbit (TSTO) system will be towed to its various airborne launch sites using a modified Boeing 747 aircraft. The RLV’s on-board turbine engines will supplement the thrust of the tow aircraft during the initial ascent. The RLV system will be released at the launch site and, using its rocket engines, ascend to stage separation. The second stage system for the specific mission will proceed to orbit. The first stage will return to its planned landing site, using its turbine engines again for powered landing on conventional runways.
Kelly’s RLV system includes a number of different upper stage vehicles, including cargo-only delivery/return vehicles, and a seven person Crew Transfer Vehicle (CTV). The system is designed to serve all current and future customers anticipated through 2030, including both government and private citizen space travelers. The system design will readily accommodate the use of customer-supplied orbit transfer stages in conjunction with their satellites or other cargoes. The CTV incorporates its own propulsion system for orbit-deorbit and orbital maneuvering needs.
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