Lightning poses a serious threat to the flight safety of aircraft. Airborne antenna, as an external structure of aircraft, is probably to become a lightning attachment point. When the antenna is struck by lightning, the end of the cable connected to the antenna may produce a short time voltage transient, and cause component failure or equipment malfunction and damage. Based on the method of combining electromagnetic simulation and experiment, the aircraft lightning indirect test of ＂induced transients in external mounted hardware＂ is studied in this paper. The induced voltage and current in the cable which is connected with the airplane components are analyzed. The work provides a basis for further research on lightning effect of aircraft external structure and lightning protection of airborne equipment.