Fine positioning optimization and maneuvers for Symphonie

The present work describes the geostationary telecommunications satellite Symphonie and its accompanying positioning system. The satellite is equipped with two TV repeaters; its weight at launching was 402 kg. The positioning maneuvers had to be optimized for rapid and reliable placement in synchronous orbit. Once in orbit, the satellite was stabilized triaxially with an inertial wheel and a cold gas guidance system. The apogee motor used a bipropellant with a large specific impulse. After stabilization is completed, electrical power was provided by three solar high-power solar panels. There were three stages in the transition from initial to final orbit: (1) quasi-synchronous circular orbit, (2) triaxially stabilized configuration, and (3) final geostationary position.