Simulation of aircraft two level maintenance concept based on Petri net

Two level maintenance (2LM) concept is the core of modern aircraft maintenance support system. It is the key to improve aircraft availability. Based on the modern aircraft maintenance support system, this paper build a running model of 2LM concept by Petri net, and have a simulation with the variable initial parameters. Furthermore, the emphasis is to contrastively analysis the effectiveness evaluation indicators of 2LM system and 3LM system, including operational availability, mission capable rate (MCR), delay and economy etc. The simulation results show that the costs of the 2LM are relatively low while maintains the same availability and MCR.