RISK MANAGEMENT FOR ORBIT INSERTION STAGE

摘要

The Space Launch Mission Risk Management shall eliminate risk avoidance practices without compromising on safety. The prime objective shall be mission design with realistic risk assessment and maximisation of data collection even from grossly failed missions. The gross under performance of lower stages results in sub orbital flight of orbit insertion stage with a probability of impact over landmasses. If the risk exceeds the acceptable level, the Range Safety Officer should inhibit the ignition of the last stage at appropriate time. The mission abort philosophy based on monitoring of current vehicle parameters is not realistic and often pessimistic. This paper presents the range safety philosophy based on real time mission simulation methodology.Trajectory simulation with onboard guidance algorithm is carried out in the range safety processor considering the instantaneous performance of the vehicle. From the present state, the total mission is simulated at every telemetry measurement cycle. The probable orbit or the impact zone of orbit insertion stage with reference to the landmasses in case of re-entry are computed and displayed. The decision-making logic includes allowing the mission to continue even the sub orbital missions if the risks are within the acceptable limits. The mission abort decision is taken if the orbit insertion stage impact is predicted on landmasses.