Equipment Mission Safety Evaluation Method Based on Function-Structure

Safety is the eternal theme of aviation activities. With the rapid development of military technology and equipment construction, the new equipment requires safer and more reliable technology and management guarantees. The aim of this paper is to evaluate the safety level of equipment in a single-stage mission. The mission safety is defined as the capacity of equipment to avoid unacceptable accidents during mission execution. A safety analysis framework is constructed according to the logic of mission-function-safety structure. The mission profile ensures the success of the mission by specifying the functional requirements and the safety structure realizes the functional requirements by adjusting the structure and scheduling resources. On this basis, the functional dependency network analysis (FDNA) method is improved to study the interaction failures between the components in the specific state. A numerical simulation method for mission safety is proposed to analyze the evolution relationship between components and behaviors, which could obtain the mission safety level under different failure modes. A case verifies the application process. The results revealed that the mission safety assessment needs to be evaluated with the consideration of safety structure and mission profile. The scale of system failures conforms to Weibull distribution in different attack modes. It is shown that the escalating risks will cause serious consequences.