Due to the highly integrated avionics systems of civil aircraft, which directly contribute to an exponential rise in the size of airborne safety-critical software, and the duality in the transfer of requirements at each level of the avionics system software, a Safety SysML consistency verifier is developed on the basis of research into safety state machines.This paper firstly introduces the syntax of Safety_SysML, followed by the design of the Safety_SysML consistency verifier, including static data detection and dynamic data detection. Finally, test cases are designed for unit and integration test of the core algorithm and system. Based on the model consistency requirements and influencing factors such as migration conditions, functional tests are designed and executed through error inference and boundaries to find defects in the verifier. The above test results and aircraft examples are used to supplement the validator to verify the correctness of the model consistency and avoid uncertain behaviour of the system. The result shows that this method can effectively identify the problem of duality in avionics system software, which is important for improving the safety and reliability of avionics software.