Aircraft Engine Control System Safety Assessment

Along with the fast development of China Civil Aviation, the demand of designing and producing civil aircraft is much higher. For the domestic large aircraft, which was expected to have more than 150 seats and independent intellectual property rights, how to ensure the safe flight and its reliability has became an urgent problem that should be solved.System Safety Assessment (SSA) establishes safety standards, assesses the compliance of the system with these standards, guides the corrective actions of the design and improvements for showing compliance of standards, and verifies the compliance of designed system with standards. How to complete aircraft system safety assessment exactly and efficiently, especially for highly complicated system (engine fuel and control system, etc.), is an important issue which need to be solved urgently. The study and digestion of the safety assessment technology is the major objective.According to the current domestic safety assessment, the models, process and motheds of safety assessment and Time Limited Dispatch (TLD) approach were studied hereby. By analyzing the application of safety assessment in engine fuel and control system of CFM56 (the engine used on Boeing 737), a relational database was established to store the failure data, and models of Functional Hazard Assessment (FHA) and Time Limited Average (TWA) were built. The airborne system safety assessment assistant system (ASSAAS) for the purpose of testing and validation was also developed. The study shows that ASSAAS has significant value for the safety assessment of highly complicated airborne system.