The turnaround time (TAT) is one of main measurement parameter for evaluating the fight capability of military airplane. In order to solve the problem of how to analysis and compute military airplane-s TAT, based on the discussion of impact factors on TAT from military airplane-s mission type, design characteristics and operational support resource, a calculation method for one military aircraft-s TAT was provided. While computing the TAT, the airplane-s mission type percentage was integrated and mission type matrix and TAT matrix was constructed. A matrix was used to define the logic relationship between work items of turnaround activity. The elements of this matrix were ranked and ordered topologically, and the results were put in sets for computing. Based on the results critical work items of each mission type TAT were determined, and the critical impacting factors on this mission type TAT were obtained. These factors will provide auxiliary decision for improving military airplane design and operational support resources planning.