A reusable space vehicle for direct descent from high orbits

It is pointed out that technologies, being developed or already existing, make possible a spacecraft flyable directly from high orbits to horizontal landing on an airstrip. Fully reusable except for two small external tanks, it could be ground-launched, or air-launched from an aircraft in the C-5 or 747 class. Air-launched the spacecraft could deliver a payload of 6000-9000 lb to Low Earth Orbit (LEO). Refueled with 90,000 lb of oxygen-hydrogen in LEO by an uprated NASA Shuttle, it could deliver payloads of 9000-16,000 lb to high orbits and then return directly to an airstrip. A crew could man the vehicle or it could be operated as an RPV. An active cooling system must protect the spacecraft from high reentry temperatures. It is believed that technologies existing or now in development would permit the considered vehicle to attain operational status in the early 1990s.