The Impact of Maintenance Distribution Structure Design on Airline's Route Robustness

Aviation operations are challenged by diverse unexpected disruptions that lead to prohibitive recovery costs, and hence enhancing the robustness of airline planning becomes of paramount importance. An effective approach should be improving the flexibility, i.e., the possibilities to swap aircraft in operations, of routes generated by the aircraft maintenance routing problem (AMRP), in which maintenance planning decisions are simultaneously made. There has been an increasing trend to outsource aircraft maintenance services, which creates a new way for airlines to modify their maintenance distribution structures. In this study, we investigate the potential effects of maintenance distribution structure on the robustness of aircraft routes, measured by the number of swapping possibilities. Based on this exploration, this study makes further efforts on robustness enhancement through additionally incorporating a robustness strategy, i.e., encouraging swapping possibilities, into the AMRP. Accordingly, a robust AMRP model and a tailored solution algorithm are proposed. Numerical experiments based on real flight operations are carried out. The results demonstrate that a strong impact of maintenance distribution structure on route robustness can be observed. More specifically, a more concentrated structure is capable of creating more swapping possibilities for aircraft routes. Furthermore, the results also suggest that, through exploiting the effect of maintenance distribution structure and awarding the generation of swapping possibilities, the routing plan resulting from our constructed model enables greater resistance to disruption