In December 2021, 27,591 aircraft took off or landed at Frankfurt airport—890 every day. But this winter, many of them weren’t carrying any passengers at all. Lufthansa, Germany’s national airline, which is based in Frankfurt, has admitted to running 21,000 empty flights this winter, using its own planes and those of its Belgian subsidiary, Brussels Airlines, in an attempt to keep hold of airport slots.
Although anti-air travel campaigners believe ghost flights are a widespread issue that airlines don’t publicly disclose, Lufthansa is so far the only airline to go public about its own figures. In January, climate activist Greta Thunberg tweeted her disbelief over the scale of the issue. Unusually, she was joined by voices within the industry. One of them was Lufthansa’s own chief executive, Carsten Spohr, who said the journeys were “empty, unnecessary flights just to secure our landing and takeoff rights.” But the company argues that it can’t change its approach: Those ghost flights are happening because airlines are required to conduct a certain proportion of their planned flights in order to keep slots at high-trafficked airports.
A Greenpeace analysis indicates that if Lufthansa’s practice of operating no-passenger flights were replicated equally across the European aviation sector, it would mean that more than 100,000 “ghost flights” were operating in Europe this year, spitting out carbon dioxide emissions equivalent to 1.4 million gas-guzzling cars. “We’re in a climate crisis, and the transport sector has the fastest-growing emissions in the EU,” says Greenpeace spokesperson Herwig Schuster. “Pointless, polluting ‘ghost flights’ are just the tip of the iceberg.”
Aviation analysts are split on the scale of the ghost flight problem. Some believe the issue has been overhyped and is likely not more prevalent than the few airlines that have admitted to operating them. Others say there are likely tens of thousands of such flights operating—with their carriers declining to say anything because of the PR blowback.
“The only reason we have [airport] slots is that it recognizes a shortage of capacity at an airport,” says John Strickland of JLS Consulting, an aviation consultant. “If there wasn’t any shortage of capacity, airlines could land and take off within reason whenever they want to.” However, a disparity between the volume of demand for takeoff and landing slots and the number of slots available at key airports means that airlines compete fiercely for spaces. In 2020, 62 million flights took place at the world’s airports, according to industry body Airports Council International. While that number sounds enormous, it’s down nearly 40 percent year on year. To handle demand, more than 200 airports worldwide operate some kind of slot system, handling a combined 1.5 billion passengers. If you board a flight anywhere in the world, there’s a 43 percent chance your flight is slot managed.
Airlines even pay their competitors to take over slots: Two highly prized slots at London Heathrow airport reportedly changed hands for $75 million in 2016, when tiny cash-rich airline Oman Air made Air France-KLM an offer it couldn’t refuse for a sleepy 5.30 am arrival from Muscat to the UK capital. “It’s all about using the ground and airspace to make the most of what you have,” says James Pearson, a route development analyst at Simple Flying, an airline consultancy. “Theoretically it’s a very good idea.”