Lunar Module Reaction Control System Oxidizer Tank and Associated Parts

Lunar Module Reaction Control System Oxidizer Tank and Associated Parts

This oxidizer tank was designed for use in an Apollo Lunar Module. It retains its shipping container, a full-scale schematic diagram, an inspection record documentation pack certifying it as 'flightworthy', and a NASA parts tag.

This type of oxidizer tank was designed for use in the Reaction Control System (RCS) on the Ascent Stage of the Lunar Module (see pics). Four sets of four thrusters made up the RCS, with thrust being directed out of any of the nozzles individually. This allowed some control of the Lunar Module, with the crew able to change its orientation and make minor movements to the spacecraft. The RCS was also used to separate the Lunar Module from the Command Module to begin the descent to the Moon.

Whilst the Descent and Ascent Engines did the brunt of the work as the Lunar Module landed and lifted off from the Moon, the RCS was used to maintain control whilst flying the spacecraft. The RCS was fed by a fuel tank, containing a hypergolic propellant (Aerozine -50), and the oxidizer tank, which contained nitrogen tetroxide. There were two tanks of fuel and two tanks of oxidizer, so that a redundant system was available at any time in case of problems occurring in any of the tanks. The tanks were kept pressurised by a flow of helium from additional tanks, with the propellant and oxidizer meeting in the nozzles of the RCS - where they mixed and ignited through a chemical reaction.

Although never deployed on a Lunar Module, this oxidizer tank was shipped to NASA in March 1970.