Export restricted (ITAR), sale only to US Citizens and Organizations. Apollo-era Marquardt R-4D rocket engine designed and tested for application as an Attitude Control, Reaction Control System (RCS) and primary propulsion thruster, measuring approximately 19.75″ tall with a diameter of 5.75″ at the nozzle, marked on the side: "Engine-Rocket, Part No. 228687-533, Ser. No. 1416, Spec. No. S73200001RE0001, Contract No. R02CGA5605…Date 1Q71." A valve at the top is marked with a Marquardt label, "Valve Assy-Solenoid, Fuel"; the adjacent ‘Solenoid, Oxidizer’ valve is missing. The engine has a rated thrust of 100 pounds, just as those used by the Apollo spacecraft did. Manufactured in the first quarter of 1971, the engine dates to the time of the Apollo program's lunar landings, with the upper platform marked in felt tip, "Apollo." The engine is sealed in a 20-gallon storage bag for protective purposes and should be handled with care; due to its status as a ‘tested’ rocket engine, it may contain residual hypergolic propellant (nitrogen tetroxide and a hydrazine derivative), which is a known carcinogen. As RR Auction cannot confirm that the engine has been properly flushed, the engine should be handled with gloves or in a sealed environment.
Originally designed by Marquardt to be used for attitude control, reaction control thruster on Apollo vehicles, the R-4D saw use in a variety of other spacecraft including the U.S. Navy's Leasat, Insat 1, Intelsat 6, Italsat, BulgariaSat-1, Japan's H-II Transfer Vehicle, and the European Automated Transfer Vehicle. The R-4D was also employed as the primary propulsion maneuver engine on the Lunar Orbiter. On the Apollo vehicles, the 100-pound thrust rocket engines were used in groups of four—configured as a 'quad'—to provide attitude control of the CSM and LM, allowing roll, yaw, and pitch maneuvers. A fantastic piece of significant space hardware made iconic with the Apollo lunar landings.
Originates from the personal collection of a former facility maintenance manager at Marquardt Corporation in Van Nuys, California.
