Aviation dc contactor because of its small volume load characteristics such as high reliability, long life, each big system is widely used in aircraft electric parts, is of great importance in modern aircraft electrical control unit air dc contactor in the process of opening and closing, the contact will get electrical erosion when erosion after reaching a certain degree, dynamic and static contact will be welded together, contactor will be out of control and important system fault in the aircraft power supply, etcBased on the fault analysis of a starter contactor of a certain type of aircraft, and combining with the average fault rate of the contactor in the past four years, the Suggestions on the timely control management of the component are put forward, which can effectively prevent the occurrence of major faults of other aircraft systems caused by the fusion welding of contactor.