Apollo command and service module

Apollo command and service module

Apollo CSM Endeavour in lunar orbit during Apollo 15
Manufacturer	North American Aviation
Designer	Maxime Faget
Country of origin	United States
Operator	NASA
Applications	Crewed cislunar flight and lunar orbit Skylab crew shuttle Apollo–Soyuz Test Project
Specifications
Spacecraft type	Capsule
Launch mass	32,390 lb (14,690 kg) Earth orbit 63,500 lb (28,800 kg) Lunar
Dry mass	26,300 lb (11,900 kg)
Payload capacity	2,320 lb (1,050 kg)
Crew capacity	3
Volume	218 cu ft (6.2 m3)
Power	3 × 1.4 kW, 30 V DC fuel cells
Batteries	3 × 40 ampere-hour silver-oxide
Regime	Low Earth orbit Cislunar space Lunar orbit
Design life	14 days
Dimensions
Length	36.2 ft (11.0 m)
Diameter	12.8 ft (3.9 m)
Production
Status	Retired
Built	35
Launched	19
Operational	19
Failed	2
Lost	1
Maiden launch	February 26, 1966 (AS-201)
Last launch	July 15, 1975 (Apollo–Soyuz)
Last retirement	July 24, 1975
Service Propulsion System
Powered by	1 × AJ10-137[1]
Maximum thrust	91.19 kN (20,500 lbf)
Specific impulse	314.5 s (3.084 km/s)
Burn time	750 s
Propellant	N2O4/Aerozine 50
Related spacecraft
Flown with	Apollo Lunar Module
Configuration
Apollo Block II CSM diagram ← Gemini spacecraft Orion (spacecraft) →

The Apollo command and service module (CSM) was one of two principal components of the United States Apollo spacecraft, used for the Apollo program, which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as a mother ship, which carried a crew of three astronauts and the second Apollo spacecraft, the Apollo Lunar Module, to lunar orbit, and brought the astronauts back to Earth. It consisted of two parts: the conical command module, a cabin that housed the crew and carried equipment needed for atmospheric reentry and splashdown; and the cylindrical service module which provided propulsion, electrical power and storage for various consumables required during a mission. An umbilical connection transferred power and consumables between the two modules. Just before reentry of the command module on the return home, the umbilical connection was severed and the service module was cast off and allowed to burn up in the atmosphere.

The CSM was developed and built for NASA by North American Aviation starting in November 1961. It was initially designed to land on the Moon atop a landing rocket stage and return all three astronauts on a direct-ascent mission, which would not use a separate lunar module, and thus had no provisions for docking with another spacecraft. This, plus other required design changes, led to the decision to design two versions of the CSM: Block I was to be used for uncrewed missions and a single crewed Earth orbit flight (Apollo 1), while the more advanced Block II was designed for use with the lunar module. The Apollo 1 flight was cancelled after a cabin fire killed the crew and destroyed their command module during a launch rehearsal test. Corrections of the problems which caused the fire were applied to the Block II spacecraft, which was used for all crewed spaceflights.

Nineteen CSMs were launched into space. Of these, nine flew humans to the Moon between 1968 and 1972, and another two performed crewed test flights in low Earth orbit, all as part of the Apollo program. Before these, another four CSMs had flown as uncrewed Apollo tests, of which two were suborbital flights and another two were orbital flights. Following the conclusion of the Apollo program and during 1973–1974, three CSMs ferried astronauts to the orbital Skylab space station. Finally in 1975, the last flown CSM docked with the Soviet craft Soyuz 19 as part of the international Apollo–Soyuz Test Project.