Apollo SPS Engine Helium Pressure Tanks

Each 40″ titanium tank carries 19.6 cubic feet of helium gas, pressurized at 3600psi. These are used to “pump” fuel and oxygen for the SPS engine. The fuel is “pumped” to the engine from the tanks by injecting this inert gas.

Stamped with NAA (photo below), North American Aviation built the Apollo CSM. This one came from 1964, and the first SPS helium tank was burst-tested in November 1963.

And these balls have served as props in some movies, and even a Eurythmics’ Dave Stewart music video. Now an artifact in the Future Ventures’ 🚀 Space Collection.