GEOS 1 and 2 in flight evaluation of the reaction control system
Abstract
The GEOS 1 and 2 hydrazine thrusters in flight performance was evaluated. The method of calculation of thruster performances, and corresponding accuracies, are presented. Results are compared to ground results from thruster acceptance and qualification tests. Attitude, orbit and spin maneuvers are studied. Thruster behavior is very satisfactory, but is better on GEOS 1 than on GEOS 2, probably due to ground contamination of catalysts. Long nonoperation periods in hard vacuum have no effects on thruster behavior. Overall efficiencies are 90% to 100%. Specific impulses are good (200 to 225 sec in pulsed mode) as confirmed by the 12.5 kg of hydrazine remaining in GEOS 2 tank after 22 months orbit life, while 30.6 kg were loaded for a 24 months expected life. There is no visible influence of aging on thruster performance.
- Publication:
-
Final Report Societe Europeenne de Propulsion
- Pub Date:
- July 1983
- Bibcode:
- 1983sepv.rept.....M
- Keywords:
-
- Flight Tests;
- Geos 1 Satellite;
- Geos 2 Satellite;
- Hydrazine Engines;
- Satellite Attitude Control;
- Aging (Materials);
- Fuel Consumption;
- Orbital Maneuvers;
- Service Life;
- Vacuum Effects;
- Launch Vehicles and Space Vehicles