A passenger demand model for airline flight scheduling and fleet routing

Fleet routing and flight scheduling are essential to a carrier's profitability, its level of service and its competitive capability in the market. This research develops a model and a solution algorithm to help carriers simultaneously solve for better fleet routes and appropriate timetables. The model is formulated as an integer multiple commodity network flow problem. An algorithm based on Lagrangian relaxation, a sub-gradient method, the network simplex method, the least cost flow augmenting algorithm and the flow decomposition algorithm is developed to efficiently solve the problem. The results of a case study, regarding a major Taiwan airline's operations, show the model's good performance.