This is an attitude control motor or the APS (Auxiliary Propulsion System) for the S-IVB (third stage) of the Saturn V launch vehicle which took men to the Moon in Project Apollo. APS motors provided three-axis control of roll, pitch, and yaw for the S-IV during Earth orbit and injection into lunar orbit. They produced 150 pounds of thrust which were generated as pulses, as required, and were designed for a life requirement of over 300 seconds. The propellant was hypergolic (self-igniting) nitrogen tetroxide as the oxidizer and monomethyl hydrazine as the fuel. The motors therefore did not require ignition systems. Each APS module on the S-IVB stage contained three 150-pound thrust motors and one 72-pound thrust ullage motor. This particular motor has been fired in tests.
The APS engines were developed from 1963 by TRW Space Laboratories. APS engines were used in all the Apollo Saturn V flights from the unmanned Apollo 4 in 1967 to Apollo 17, the last lunar mission, launched on 6 December 1972. The Saturn V last flew when it lifted Skylab, the U.S.'s first Earth-orbiting space station on 14 May 1973.
Display Status
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Date
1967
Country of Origin
United States of America
Type
PROPULSION-Rocket Engines
Manufacturer
TRW, Inc., Electromechanical Division
Dimensions
Overall: 1ft 5 1/4in. x 1ft x 7 1/4in. (43.82 x 30.48 x 18.42cm)
Materials
Nozzle and chamber: phenolic impregnated silica with fiberglass overwrap
Nozzle: sprayed zirconia coating
Other: steel, non-ferrous metal, plastic, aluminum, paper, adhesive
Inventory Number
A19740783000
Credit Line
Gift of McDonnell Douglas Astronautics Company
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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