Performance evaluation of the SIRIO maneuver system

This paper describes the SIRIO maneuver system which consists of the on-board Attitude and Orbit Control system (AOC) and the set of computer programs known as the Flight Dynamics System (FDS). The ground antenna, the telemetry and command subsystem also constitute an important part of the manuever system, but they are not dealt with here because their functioninf does not influence manuever execution logic. A brief outline is given of the AOC hardware involved with manuever execution. The basic maneuver planning logic, i.e. orbital, attitude and spin rate corrections, is described. The description is limited to problems concerning the geostationary phase of the mission although considerations and data relative to the station acquisition maneuvers are given, eherever they are felt to be useful for a deeper understanding of the maneuver system. There is also a description and an evaluation of the programming tools used in planning and controlling maneuver execution. Tables containing data relative to all the maneuvers executed on SIRIO are presented and commented.