Hazard Analysis of Complex Spacecraft Using Systems-Theoretic Process Analysis

A new hazard analysis technique, called systems-theoretic process analysis, is capable of identifying potential hazardous design flaws, including software and system design errors and unsafe interactions among multiple system components. Detailed procedures for performing the hazard analysis were developed, and the feasibility and utility of using it on complex systems was demonstrated by applying it to the Japanese Aerospace Exploration Agency H-II Transfer Vehicle. In a comparison of the results of this new hazard analysis technique to those of the standard fault tree analysis used in the design and certification of the H-II Transfer Vehicle, systems-theoretic hazard analysis found all the hazardous scenarios identified in the fault tree analysis as well as additional causal factors that had not been identified by fault tree analysis.