This is the Thrust Chamber Assembly that fits on top of the nozzle of the Apollo Service Module Propulsion System (SPS). The large nozzle is not shown. The SPS engine was mounted at the base of the Apollo Service Module. Apollo astronauts used the SPS to steer their spacecraft toward the Moon, place it into lunar orbit, and propel it back toward Earth.
Using storable propellants, the SPS had a thrust of 21,900 pounds and could operate for from 0.4 seconds to 12.5 minutes, as required. The SPS engine served successfully on all Apollo missions. This SPS Engine Thrust Chamber is an engine development model which was used for engineering tests. It was donated to the Smithsonian in 1986 by the NASA Johnson Space Flight Center.
Transferred from NASA/Johnson Space Center