Disruptions in the airline industry: math-heuristics for re-assigning aircraft and passengers simultaneously

In this paper, we propose an oscillation strategy heuristic combined with mathematical programming for disruption management in the airline industry (DMAI). The goal of this problem is to resume normal operations as quickly as possible during the recovery period while minimising the resulting costs and the potential impacts to passengers. In cases of disruptions, DMAI aims to reassign aircraft and passengers simultaneously rather than according to the natural hierarchy of aircraft, crews and passengers. In this problem, we consider many types of practical disruptions, such as mechanical failures, personnel strikes or inclement weather. Just finding a feasible flight schedule is a hard problem. Our method can be divided into two main stages: in the first stage, we try to generate a feasible solution to the problem; in the second, we improve this solution using an oscillation strategy that alternates between constructive and destructive phases. Our numerical results show the effectiveness of this method, which produced the best results known for some of the most demanding instances of a real-life problem. With these results, we ranked 2nd in an international challenge. [Received 10 September 2009; Revised 18 May 2010; Accepted 26 October 2010]