Measuring the vulnerability of global airline alliances to member exits

We analyse the vulnerability of airline alliance route networks to the exit of member airlines. Vulnerability measures how easy it is to disconnect a network. The assessment is performed by applying the theory of complex networks. We compute the normalized vulnerability for Star Alliance, oneworld and SkyTeam using airline schedules data and derive a ranking of member airlines according to their share in the overall vulnerability of the respective alliance. One result of our paper is that oneworld is the most vulnerable global airline alliance, SkyTeam ranks second, followed by Star Alliance.