An aircraft and schedule integrated approach to crew scheduling for a point-to-point airline

Crew costs make up the second largest expense for airlines, behind only fuel costs. This motivates a potential gain in improving crew efficiency within the bounds set by the law and collective labour agreements. Doing so requires to take into account aircraft routes and crew pairings, and the specifics of the airline’s network. This work presents an integrated model for obtaining efficient crew pairings for airlines operating point-to-point networks, while also allowing for flight retiming. By considering simultaneously both crew pairing and constrained aircraft routing, better-performing solutions can be obtained. The greater complexity of the integrated model is addressed by means of a custom branch-and-price approach with a shortest path pricing sub-problem, in order to obtain exact solutions. The results of the integrated model are evaluated on a real-world case of an European low-cost carrier that operates a short-haul point-to-point network. Results show a reduction in crew duties of 10% and an increase in crew efficiency metrics by up to 1.5%, optimising the carrier’s complete network of 926 flights over a full week.