Abstract: In order to resolve the safety incidents caused by the contradiction between the maintenance capability of the airline maintenance department and the sustainable safety development of the airlines, the main business activities of the maintenance department were systematically analyzed, and a simulation dynamic model was built for the relationshios between the maintenance support capability and the sustainable safety development by using SD method. Through simulation by Vensim, effects of variables such as the workload of the maintenance staff, the employment rate of the new staff, the promotion rate of the senior staff, the approval rate of the aircraft material purchasing plan and the importing rate of the maintenance tools and equipment, on both the number of unsafe events and the quantity of the maintenance supporting flights. The study demonstrates that the strategy of ensuring the punctuality of the airline flight improves greatly the quantity of the maintenance supporting flights, but raises thenumber of unsafe events, that the strategy of ensuring the quality of aircraft maintenance lowers the number of unsafe events, but hinders greatly the development of airlines, and that the strategy giving consideration to both the maintenance capability of the airline maintenance department and the sustainable safety development of the airlines guarantees the maintenance safety, as well as the sustainable development of the airlines.

Key words: aviation maintenance, support capacity, sustainable safety, civil aviation development, system dynamics(SD)