ROC Credit - NASA

The Reusable Orbital Carrier (ROC) was a 1964 Lockheed study of a sled-launched HTHL TSTO. The booster's rocket engines would burn liquid oxygen and jet fuel while small turbojets would be used for landing approach. The 2nd stage orbiter rocketplane would make an unpowered glide return and landing. LOX, LH2 rocket propulsion would be used on the second stage. The gross liftoff weight would be about 453t and the vehicle could deliver ten passengers+3000kg to a space station. Alternatively, an unmanned 11,340kg payload could be carried.

The expected development cost was $3 billion at 1964 rates ($16 billion at 1999 rates) and the cost per flight was $100/lb, or $1,184/kg at 1999 rates. NASA saw the small 10-passenger ROC as a vehicle to prove out in small scale a larger 100-passenger "Reusable Aero-Space Transport" for the 1980s. RAST would use high-pressure oxygen+hydrogen engines and turbojets for landing on both stages. The booster rocketplane would be a multipurpose vehicle, with the 2nd stage being tailored to fit specific applications such as global passenger transportation, NASA space station resupply or military missions. The designers felt ballistic "recoverable" vertically launched vehicles make more sense for launching heavy unmanned one-way payloads, since the recovery system (chutes or retrorockets) will cost less. On the other hand, winged vehicles and lifting recovery will be safer for returning manned crews. The marginal cost per flight and the turnaround time will also be less, if the flight rates are high enough.

Manufacturer: Lockheed. LEO Payload: 11,340 kg (25,000 lb). Associated Spacecraft: Reusable Orbital Carrier. Total Mass: 453,000 kg (998,000 lb). Development Cost $: 3,000.000 million. in: 1964 average dollars. Launch Price $: 2.500 million. in: 1964 price dollars.

• Osmun, Space/Aeronautics, "Reusable Launch Vehicles", 1964/September/p.43.

• Heppenheimer, T A, The Space Shuttle Decision, NASA History Office, NASA SP-4221, 1999.

• Spaceflight, "Space Transporter Study", 1965/p.124.