The Financial Times reports on government findings that one-third of London Heathrow Airport’s passengers are on connecting flights, which magnifies “[t]he importance of the role that connecting passengers play at the UK’s busiest airport [that] has long been a source of conflict among campaigners for and against a third runway.” The issue is a hot button in UK politics, with the opposition Conservatives dead set against a new runway and London’s mayor proposing a new airport in the Thames estuary east of the city.
The figures on transfer passengers illustrate the network effect benefits of big hubs like Heathrow. Today, more than 76 percent of connecting passengers connect from one non-UK destination to another — up from 57 percent twenty years ago. These connections redound to the benefit of London travelers as well, who have more destinations than their city alone would otherwise support. “Without [connecting passengers,] the scale of the network and range of destinations as well as the number of daily services that can be supported on routes would suffer, damaging Heathrow’s attractiveness compared to European rivals such as Paris Charles de Gaulle, Frankfurt and Amsterdam Schiphol.”
Building a new airport — a perennial idea — would do little to improve Heathrow as a hub. If Heathrow is not improved as a hub, it will eventually fall behind Frankfurt, Paris-Charles de Gaulle, Amsterdam, and Madrid-Barajas as a major connecting hub. London doesn’t need a new airport; it has three perfectly good ones, all of which can be reasonable expanded, and two smaller ones. What it needs is a hub that can compete on even ground with its European rivals.