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astronautix.com R-40A


Designer: Marquardt. Propellants: N2O4/MMH Thrust(vac): 394 kgf. Thrust(vac): 3.87 kN. Isp: 306 sec. Mass Engine: 10 kg. Diameter: 0.5 m. Length: 1.0 m. Chambers: 1. Chamber Pressure: 10.50 bar. Area Ratio: 100.00. Country: USA. Status: In Production.

This thruster was developed for Shuttle Orbiter orbit control. The vehicle carries 38 in long scarf, short scarf, or no scarf configurations. Depending on the location of it. Applications: spacecraft orbital maneuvering, perigee kick engine. First Flown: April 1981 on the Columbia. Dry Mass: 10.25 kg. Length: 55.4 cm short scarf version, 103.9 cm for the long scarf, and 88.9 cm for the satellite version. with 100:1 Expansion Ratio: Maximum. Diameter: 30.9 cm long scarf version, and 51.8 cm for the satellite version with 100:1 Expansion Ratio: . Mounting : fixed . Engine Cycle: pressure-fed. Oxidizer: nitrogen tetroxide at 0.838 kg/sec at 16.4 atm. Fuel: MMH at 0.52 kg/sec at 16.4 atm. Mixture Ratio(O/F): 1.6. Thrust: 3870 N (range 3114 - 5338 N). Isp: 281 sec (306 sec for 120 expansion ratio). Expansion Ratio: 20 (40 - 150 available for satellite version). Exit Diameter: 267 mm (328 - 635 mm for satellite version). Chamber Pressure: 10.5 atm. Combustion Chamber: single chamber of silicide-coated columbium (niobium) with welded-on orthogonal and scarfed nozzle extension in same material with internal film cooling. Exterior insulated for buried installation. Started by electrical signal to on/off solenoid valve. Multiple doublet injector with hypergolic ignition.. Burn Time: max 500 sec for single burn, qualified to 15,319 sec life. 289 Ns min impulse bit..


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Last update 12 March 2001.
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