The time cost of saving money: detouring and connecting time losses in the virtually interlined European airport network.

Virtual interlining, the use of actively marketed self-connecting flight itineraries, is often assumed to be a money-saving air travel strategy. Earlier research on this topic broadly confirmed the money-saving character of virtual interlining, but to date non-monetary costs associated with this price advantage have not yet been systematically examined. In this paper, we address this lacuna by juxtaposing the price advantage of virtual interlining with the potential time costs for the case of indirect flight itineraries in the European airport network. Focusing on those markets where the cheapest virtually interlined itinerary renders a price advantage over its indirect traditional counterpart, we analyse the time cost from two complementary perspectives: (1) connecting time and (2) detour factor. To this end, we query Kiwi.com's Tequila platform to obtain data on all available flight itineraries in the first week of August, October and December 2019. Based on a series of sign tests, we reveal the time costs of saving money: while virtually interlined itineraries render a price advantage compared to their indirect traditional counterparts, they come with a significantly larger connecting time and detour factor. We reflect on possible explanations, and highlight a number of avenues for future research.

Supplementary information: The online version contains supplementary material available at 10.1186/s12544-022-00551-4.