Consider a flight that operates on less than 10% passenger capacity! In an industry that is hard pressed for funds, particularly after the Covid-19 pandemic decimated air travel, it is something very difficult to comprehend.
But a recent report in the UK’s Guardian newspaper said that 5,000 “empty”, and 35,000 flights with less than 10% occupancy, had flown in the United Kingdom since 2019!
Termed by some as “ghost flights”, they are generally considered to be aircraft that operate on less than 10% passenger capacity, according to the International Air Transport Association.
The UK story had “significant flaws”, however, IATA noted.
Firstly, this period covered the pandemic, which was completely unrepresentative of a normal air transport market.
Secondly, no context was given around the numbers. 40,000 sounds a lot, but in the context of the 4,566,382 flights that took place in the United Kingdom over that period — even during the unprecedented Covid-19 collapse in traffic — that comprises less than 1% of all flights.
Of course, any flight that takes place almost empty is bad for the environment and bad for airline finances. But precisely for these reasons, airlines don’t operate ghost flights without cause.
The analysis in the Guardian failed to explain that many of these flights were cargo flights, carrying vital supplies, including vaccines and personal protective equipment, during the pandemic. The cargo demand and humanitarian need justified the operation of certain flights, even with low passenger load factors.
Similarly, there were a number of repatriation flights, or flights where passenger numbers were deliberately restricted to comply with Covid regulations set by governments.
Additionally, there are always some flights to move aircraft to maintenance facilities or, as was the case during the pandemic, fly a significant number into storage.
Flights to protect slots?
Were any of these flights simply slot blocking? The 80-20 ‘use-it-or-lose-it’ rule was obviously not designed to work during a 95% collapse in demand, and the slot rules were cited as a potential cause of some flights having to operate unnecessarily in Europe.
But this was not the case in the United Kingdom, where the slot rules were suspended, IATA noted in a recent analysis.
There was a risk that some unnecessary flights could happen in the EU because the European Commission was too quick to restore higher slot use rates. However, for the most part during the pandemic, the slot rules were just about flexible enough that ghost flights were not a major issue.
IATA Director General Willie Walsh said: “I’m not aware of any airline company that I have worked with deliberately operating an empty flight simply to maintain a slot.”
The ghost flights non-story has, however, raised important questions that need to be answered on slot allocation rules. The European Union is looking again at its Slot Regulation, with a consultation in place leading to a potential revision of the rules in 2023.
Although the revision is focusing on wider issues of competition, accessibility, and capacity, the role of slot rules in promoting greener flying is also in the mix. In addition to international efforts to reach net-zero carbon emissions, the European Union has instigated its own initiatives through the EU Green Deal.
Some politicians erroneously believe the slot system is creating ghost flights or that the slot process should be used as part of the Green Deal to prioritise the use of quieter or more fuel-efficient aircraft.
Aviation is committed to exploring a multitude of options for reaching net-zero CO2, but airlines are united in their view that slot allocation decisions linked to the environment will not help the industry achieve its global sustainability objectives.
“The pandemic was an exceptional period and extrapolating lessons or making policy changes based on the industry’s activities during this time would be a huge category error,” says Lara Maughan, IATA’s head (Worldwide Airport Slots). “Fiddling with the slot process to try to promote greener flying sounds positive in theory, but in practice it would make the slot process even more complicated while having minimal environmental gain. Trying to micro-manage slots may even have a detrimental environmental impact.”
Part of the reason for this is the globally co-ordinated nature of the slot system. Airlines operating between two slot-coordinated airports must be able to work to a harmonised system of rules to best match demand with their planned schedule.
If one country’s rules insist on operating the slot with a certain aircraft (for example for environmental reasons), then the airline may have to prioritise a non-optimal plane for that route, regardless of volume of demand—for example a narrowbody plane over a widebody.
This, IATA said will affect consumer access and choice, and potentially impact another route that would have benefited from that aircraft choice.
Any attempt to micro-manage the process at a handful of global, slot-constrained airports will only displace aircraft elsewhere, making no overall improvement to emissions and negatively affecting the benefits of aviation connectivity for travellers and the economy.

Pratap John is Business Editor at Gulf Times. Twitter handle: @PratapJohn