A systematic risk management approach employed on the CloudSat project

The CloudSat Project has developed a simplified approach for fault tree analysis and probabilistic risk assessment. A system-level fault tree has been constructed to identify credible fault scenarios and failure modes leading up to a potential failure to meet the nominal mission success criteria. Risk ratings and fault categories have been defined for each low-level event (failure mode) and a streamlined probabilistic risk assessment has been completed. Although this technique or process will mature and evolve on a schedule that emphasizes added value throughout the development life cycle, it has already served to confirm that project personnel are concentrating risk reduction or elimination/retirement measures in the appropriate areas. A cursory evaluation with an existing fault tree analysis and probabilistic risk assessment software application has helped to validate this simplified approach. It is hoped that this will serve as a model for other NASA flight projects.