https://en.wikipedia.org/wiki/Apollo_command_and_service_module
helium tanks for the CM reaction control subsystem
1. What was the purpose of using helium in the Apollo CM?
The Apollo Command Module (CM) used helium for a variety of purposes, including pressurizing the fuel tanks, cooling the electronics, and providing a breathable atmosphere for the astronauts.
2. How was helium used to pressurize the fuel tanks in the Apollo CM?
Helium was used to pressurize the fuel tanks in the Apollo CM because it is an inert gas that does not react with the fuel. This helped maintain a constant pressure in the tanks and prevent the fuel from boiling off in the vacuum of space.
3. Why was helium used to cool the electronics in the Apollo CM?
Helium has excellent thermal conductivity, making it an ideal choice for cooling the sensitive electronics in the Apollo CM. It was used to transfer heat away from the electronics and dissipate it into the surrounding environment.
4. Did the astronauts breathe pure helium in the Apollo CM?
No, the astronauts did not breathe pure helium in the Apollo CM. The helium was mixed with oxygen to create a breathable atmosphere for the astronauts. This mixture helped maintain a safe and comfortable environment for the crew during their mission.
5. How much helium was used in the Apollo CM?
The Apollo CM used approximately 80 pounds of helium for various purposes. This included pressurizing the fuel tanks, cooling the electronics, and providing a breathable atmosphere for the astronauts. This amount was carefully calculated and monitored to ensure the success of the mission.