a spacecraft designed for flight with a crew on board. Manned spacecraft are distinguished by sealed cabins, with life-support systems for the astronauts. Spacecraft designed for geocentric orbit are called manned orbital spacecraft, and those designed to fly to other heavenly bodies are called manned interplanetary (expeditionary) spacecraft. Reusable space shuttles are being developed to transport passengers and cargo from earth to low geocentric orbit and back —for example, to a long-term orbital station. The transport of passengers and cargo from a low geocentric orbit to a higher orbit, even a stationary orbit, is envisioned, using unmanned rocket-powered space tugs. Plans for manned and unmanned space tugs for transfer from a geocentric orbit to a lunar or planetary orbit and back are being studied.
Manned spacecraft that have been developed and flown include the Soviet orbital spacecraft of the Vostok, Voskhod, and Soyuz series (the Soyuz may serve as a nonreusable transport craft) and the American orbital spacecraft of the Mercury and Gemini series and the expeditionary Apollo spacecraft for lunar flights. The Apollo spacecraft may serve as a nonreusable transport craft for flights to geocentric and lunar orbits. Such spacecraft consist of several compartments and are equipped with systems for life support, propulsion, navigation and guidance, power supply, communications, emergency rescue, and reentry.
REFERENCESPilotiruemye kosmicheskie korabli: Proektirovanie i ispytaniia; Sb. st. Moscow, 1968. (Translated from English.)
Osvoenie kosmicheskogo prostranstva ν SSSR. Moscow, 1971.
G. A. NAZAROV