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    Apollo Program Hardware: Reaction Control System Helium Check Valve Assembly for Command/ Lunar Modules. Manufactured by Accessory Products Company (APCO). This 4.75" x 2.125" x 2.375" device is a double helium pressurant check valve: one side for oxidizer (nitrogen tetroxide) and one side for fuel (hydrazine). Helium is the pressurizing gas used in these small rocket engines used to correct the attitude of the space craft. This valve prevented the propellants or their vapors from flowing back into the helium pressurant system should there be a failure of one of the propellant tank bladders or a sudden depressurization of the helium pressurant system. This part has both the Apollo Command module master contract number NAS 9-150 and also a Grumman Aircraft Engineering Company (GAEC) SCO number LSC 310-306-3. Grumman was the master contractor of the Apollo Lunar Module. Four protective caps are included for the studs (not shown in images). Displays nicely. Excellent.

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    Auction Dates
    November, 2013
    1st Friday
    Bids + Registered Phone Bidders: 7
    Lot Tracking Activity: N/A
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