ESA GNC Conference Papers Repository

The paper presents the LEOP main events and rescue plan applied on PALAPA-D to recover as much lifetime as possible following LM3B launch anomaly. Evidence of low performance of the 3rd stage engine appeared a few minutes after the launch of 31st August 2009. Recovery actions were engaged by the Thales Alenia Space recovery team that was immediately setup. Perigee Velocity Augmentation maneuvers had to be performed first to increase the apogee to 36000km in order to optimally correct the inclination with further Apogee Motor Firing. The Star Trackers were a key element to the safe and successful recovery plan : with another standard AOCS design based on earth sensors, no precise 3 axis pointing would have been achieved (SC to close from earth to allow earth capture in earth sensor field of view). Spacebus 4000 AOCS based on Star Trackers allowed fast, accurate and efficient maneuvers that maximized the remaining lifetime.