Combinational Aspects of Move Up Crews

Summary In railway planning, a frequent problem is that a delayed train necessarily delays its crew. To prevent delay propagation along the crew‘s succeeding trips, a move-up crew may take over the rest of the crew‘s duty on time. We address two problems in this context: First, during the planning stage, one has to make a tradeoff between robustness gained and additional costs incurred by introducing move-up crews. We suggest different heuristics to solve this problem, depending on the size of the instance. Second, during operations, dispatchers have to make optimal crew swap decisions, i.e., use available move-up crews to minimize overall passenger delay. For the local case, we give an efficient algorithm. However, optimizing crew swaps over the whole railway network is NP-hard