Joint optimization using a leader–follower Stackelberg game for coordinated configuration of stochastic operational aircraft maintenance routing and maintenance staffing

The flight delay-based operational aircraft maintenance routing problem (OAMRPFD) and the maintenance staffing problem (MSP) are interrelated and interdependent. Despite this interdependency, each problem is solved separately. Therefore, the optimal plan specified by each problem is not executed as planned, which consequently increases the operating cost of each aspect of the problem. The present research paper studies OAMRPFD in addition to MSP, with two main objectives. The first is to develop an OAMRPFD model that appropriately reflects the flight delay and, accordingly, a new stochastic framework of a scenario-based OAMRPFD (SOAMRPFD) is put forward. The second is to handle the interdependence between SOAMRPFD and MSP, by proposing a coordinated configuration of SOAMRPFD and MSP that is formulated like the leader–follower Stackelberg game, with SOAMRPFD as the leader and MSP as the follower. A bi-level optimization model is used to present this game and is solved by a bi-level nested ant colony optimization (ACO) algorithm. The viability and potential of the proposed model are established using a major airline and a maintenance company, which are based in the Middle East, as a case study. The results demonstrate significant cost savings for both the airline and maintenance company.