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R-4D
Marquardt-built small hypergolic rocket engine / From Wikipedia, the free encyclopedia
For the aircraft with this designation in US Navy service, see Douglas C-47 Skytrain.
The R-4D is a small hypergolic rocket engine, originally designed by Marquardt Corporation for use as a reaction control system thruster on vehicles of the Apollo crewed Moon landing program. Aerojet Rocketdyne manufactures and markets modern versions of the R-4D.[1]
Quick Facts Country of origin, Manufacturer ...
![]() RCS quad containing four R-4D thrusters, as used on the Apollo Service Module | |
Country of origin | United States |
---|---|
Manufacturer | Kaiser Marquardt Aerojet Rocketdyne |
Application | Reaction control system |
Liquid-fuel engine | |
Propellant | NTO / MMH |
Cycle | Pressure-fed |
Performance | |
Thrust, vacuum | 110 pounds-force (490 N) |
Thrust-to-weight ratio | 13.74 |
Chamber pressure | 100.5 pounds per square inch (6.93 bar) |
Specific impulse, vacuum | 312 s |
Dimensions | |
Length | 12.00 inches (30.5 cm) |
Diameter | 6.00 inches (15.2 cm) |
Dry mass | 8.00 pounds (3.63 kg) |
Used in | |
Orion (spacecraft) H-II Transfer Vehicle (1, 2, 4) Space Shuttle Apollo (spacecraft) Cassini (spacecraft) ESA Automated Transfer Vehicle |
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