Rocket Engine, Liquid Fuel, Reaction Control System (RCS), SE8-9, for Apollo 4

This is a Reaction Control System (RCS) rocket engine for the yaw control of the Apollo space craft. It was flown on Apollo 4, launched in November 1967. This was the first flight of the Saturn V in which the Command Model (CM) made three orbits followed by a successful reeentry and splashdown. It was a crucial mission and verified the first "all up" test of all stages of the the Saturn V. The RCS system consisted of twelve engines in all operating in tandem. The system produced small pulses or bursts thrusts as needed over a 30 minute mission period. The pulses placed the CM in its proper position for re-entry into the Earth's atmosphere. This RCS was transferred to the Smithsonian in 1977 by the NASA Johnson Space Flight Center.