This page no longer updated from 31 October 2001. Latest version can be found at 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..

Back to Index
Last update 12 March 2001.
Definitions of Technical Terms.
Contact Mark Wade with any corrections or comments.
Conditions for use of drawings, pictures, or other materials from this site..
© Mark Wade, 2001 .