Generation of aircrew schedules using repeated matching

We consider the aircrew scheduling problem of determining tours of duty (TODs) for aircrews, given a set of sectors (or flights) requiring regular crews. A regular crew consists of two crew members, but by including an additional crew member (a third pilot) on some sectors it is possible to generate more cost efficient TODs. A related problem is thus to generate TODs for these third pilots, but the number of sectors requiring a third pilot is not known in advance. To solve these two related problems we apply a heuristic procedure that solves a sequence of matching problems, i.e. a repeated matching algorithm. Numerical results based on data and regulations from an actual airline show that this approach is indeed a valid and efficient one for the TOD scheduling problem.