Abstract:As the only supporting structure of the aircraft, the aircraft landing gear is an indispensable part of the aircraft. The main landing gear is usually installed on the wing, and the aircraft fuel tank is often a part of the wing structure. When the main landing gear system is damaged due to overloading during take-off and landing of the aircraft, its damage mode may cause damage to the aircraft fuel tank, resulting the fuel system to overflow enough fuel to pose a fire hazard, thus threatening the lives and property of passengers. Therefore,the main landing gear needs to be designed as an emergency disconnect structure so that the main landing gear can be separated from the body in order to protect the safety of the fuel tank. This paper studies the design and verification of the insurance pin of the main landing gear of a civil aircraft, including the structure design, strength check and test verification of the fuse pin. The test verification of the safety pin was carried out by designing a test rig that is different from the landing gear connection form and obtaining the correction coefficient of the test rig through simulation analysis. Then the test rig model was modified according to the test results, and the structural size of the fuse pin was finally determine.