NASA Office of Logic Design

NASA Office of Logic Design

A scientific study of the problems of digital engineering for space flight systems,
with a view to their practical solution.

"Apollo Reaction Control Systems"

Chester A. Vaughan
Manned Spacecraft Center, Houston Texas

Paper No. 68-566
AIAA 4th Propulsion Joint Specialist Conference
Cleveland, Ohio
June 10-14, 1968

Descriptions of the reaction control systems for the Apollo command module, service module, and lunar module are presented. Major problems encountered during the development and qualification of the engines for these systems are discussed. These systems are pressure fed, bipropellant, hypergolic propulsion systems utilizing nitrogen tetroxide as the oxidizer and the hydrazine group of fuels. A total of 44 reaction control system engines are installed in the three modules. The Apollo reaction control system must satisfy many unique environmental requirements ranging from zero-gravity propellant feed to operation with the reaction control system engine in a gravitational field firing vertical up. Operational requirements range from short on-off to long on-off firing times. Total impulse requirements from a single firing range from 0.4 to 50 000 pound-seconds. Ten thousand firings may be required of some engines. Three Apollo command module and service module flights and one lunar module flight have been made. In each flight, the reaction control system performed its required functions successfully.


Abstract; Introduction; Service Module Reaction Control SystemLunar Module Reaction Control SystemCommand Module Reaction Control System

Development PhilosophyHot Phase Burning; Ignition Pressure SpikesIgnition Manifold Explosions; Command Module RCS EngineFlight Experience


.zip file

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