How “Ghost Flights” May Threaten Sustainability in Commercial Aviation

DALLAS - For the past two years, near-empty flights have haunted the skies of Europe. These “ghost flights” became common in the early days of the pandemic, a product of contractual obligations between airlines and airports that required a minimum number of flights to hold onto valuable airport slots.

However, more than two years after the beginning of the pandemic, these ghost flights are still common. This suggests they may have become a long-term issue the industry must tackle.

What Are Ghost Flights?

Ghost flights are planes operating at less than 10% capacity. Airlines fly them to retain airport slots, which allow the airline to land or take off from an airport at a specific time. If airlines don’t fly enough flights into or out of a specific airport, they can lose these slots.

Before the pandemic, airlines needed to make 80% of reserved takeoff and landing times in order to retain these airline slots. Otherwise, these slots would be freed up for other airlines, potentially preventing the original airline from operating at an airport altogether.

These airport slot rules were suspended early during the pandemic as demand for air travel crashed. In October 2021, the policy was reinstated at 50% of scheduled flights. Despite this lower threshold and the increase in demand for air travel, however, the number of ghost flights has remained high.

Flight data acquired by the Guardian suggests that airlines in the U.K. are flying around 500 ghost flights per month. A Greenpeace analysis of Lufthansa data on ghost flights suggests that airlines flew as many as 100,000 ghost flights in Europe in 2021.

How much of an impact do these ghost flights have? Industry analysts are divided. Some believe the problem is likely overblown and that analysis from groups like Greenpeace makes ghost flights seem more frequent than they actually are. These experts sometimes say the rising demand for air travel will soon eliminate the ghost-flight problem.

Others believe that current estimates of ghost flights are likely accurate and that they could suggest a serious problem with the current business model of both airlines and airports. Even with rising air travel demand, these ghost flights could continue to stick around, wasting valuable resources and labor.

Environmentalists have also criticized the practice heavily. The high carbon cost of flying means empty flights can have a serious environmental impact. The same Greenpeace analysis that estimated the total number of European ghost flights also estimated that these flights were producing carbon dioxide emissions equivalent to 1.4 million cars.

Many airlines running these ghost flights, like Lufthansa (LH), have publicly committed to sustainable business management. The environmental impact of these ghost flights would suggest that these airlines are not as sustainable as they claim to be.

How Can the Aviation Industry Manage Ghost Flights?

Because ghost flights are likely to remain a problem well into the future, airlines should take steps to combat these flights, or find ways to reduce their environmental impact.

For example, the industry could attempt to capitalize on these ghost flights and reduce the number of empty planes that fly each month.

Airlines could offer discounts, special rates, or other promotions to attract customers to empty or near-empty flights. With apps, emails, and even sites dedicated to finding cheap ghost flights, the industry could advertise specifically to customers who would prefer to fly on near-empty planes.

While these strategies wouldn’t fix the lack of demand and contractual obligations driving ghost flights, they could help offset some of the losses and environmental impacts that come with ghost flights.

The problem of ghost flights is similar to an issue that has emerged in the private jet industry – empty-leg flights. These are empty flights that occur when a private jet needs to reposition itself or return to its home base.

In order to capitalize on these flights, a number of private jet companies have begun to advertise their empty leg flights. Some businesses have even developed apps that allow customers to book scheduled empty-leg flights, allowing them to access private air travel at significantly reduced rates.

While empty-leg flights are not exactly the same issue as ghost flights, a similar approach in commercial aviation could help the industry make the most of flights that would otherwise be empty. While flying on a nearly-empty plane may be off-putting for some, the possibility of cheaper-than-usual fare and more room while in-flight may appeal to certain flyers.

How Airports Could Help Solve the Ghost Flight Crisis

It’s also possible for airports to simply change their policies on airport slots. Airports could do away with the system entirely or use the current crisis as an opportunity to invent a new system for managing airport takeoff and landing slot scheduling.

Going beyond a simple quota could help eliminate ghost flights altogether. For example, some experts have proposed a system where airports auction off takeoff and landing slots, rather than relying on historical airport slot use.

As demand for air travel returns to normal, however, airports may be unwilling to adopt an entirely new policy on airport slots. The old policy worked fine before the pandemic, and if demand returns to pre-pandemic levels, it would probably work fine again. Adjusting the policy now could lead to problems down the line if demand begins to outstrip available airport space again.

Airports and airlines could be in a stalemate so long as the future of the industry remains uncertain. Because many experts remain unwilling to make firm predictions on future demand for air travel – and because air travel demand has been so unpredictable over the past two years – it’s possible that airports may not have the certainty they need to take decisive action on the airport slot system.

What Ghost Flights Could Mean for the Future of Aviation

Empty and near-empty ghost flights could remain a problem for airlines well into the future even as demand increases. These empty flights are both expensive and generate significant amounts of carbon dioxide emissions.

Airlines could take steps to make these ghost flights more sustainable by investing in new systems that connect flyers with planes that are on track to fly empty. The aerospace industry keeps innovating at a regular pace, but many commercial airlines are still thinking inside the box when it comes to business models.

Airports could also review the current airport slot system that has led to the emergence of ghost flights. A new system could make the allocation of airport slots less likely to generate ghost flights.

Featured image: Lukas Souza via Unsplash