A safety analysis method for FGS based on STPA

Abstract

Flight Guidance System (FGS) plays a vital role in the avionics system. It is one of the main components of the Flight Control System (FCS). Because of its safety and inherent complexity, it becomes particularly important to analyze its safety properties. Nowadays, the safety analysis of Flight Guidance System mainly based on formal modeling and the validation of safety requirements. However, in terms of how to capture the safety requirements is not too much. Therefore, this paper proposed a set of safety analysis method based on System Theoretic Process Analysis (STPA), that implements safety analysis of Flight Guidance System and capture the safety requirements from the aspect of system interaction. Follow the steps of System Theoretic Process Analysis, first of all, we build control structure diagram, and then add process model variables, finally get the safety requirements of Flight Guidance System by establishing context table.