The representative body for the world’s airports, Airports Council International (ACI) World, has called for a global reform of the airport slot allocation system. This is the means by which air traffic controllers regulate landings and take-offs at airports, each airliner having an assigned “slot” in both cases. ACI World made this call in a White Paper entitled 'Airport Slot Policy – Rethinking Airport Access in a Capacity-Constrained World', which highlights that the current system was developed more than half-a-century ago.

“We are trying to run a 2026 aviation industry on a 1970s operating system,” pointed out ACI World director-general Justin Erbacci. “Airports are doing their best to operate within an outdated regulatory framework, but the reality is that these inflexible rules and practices are preventing the industry from adapting to modern passenger demands, providing competitive fares and building resilient networks. ACI World urges regulators to sit down with the industry and finally deliver the overdue upgrade that our passengers deserve.”

The number of the most congested airports in the world, with consequent slot restrictions (limiting the number of aircraft that can use them) has grown by more than 25% over the past ten years. As global air passenger traffic is expected to increase by almost 100% over the next 20 years, this trend will only accelerate.

Further, less than 10% of the world’s airports handled almost 66% of all passengers. Of the busiest airports – those handling more than 40-million passengers a year – 85.5% are already at, or near, full capacity, in slot terms.

However, there is little transparency regarding decisions on slot allocation. More visibility is needed about who is applying for airport access for their aircraft, who is granted that access, and why. That will allow the more efficient use of airport infrastructure for the interests of all.

Another issue is historic slot rights, which accumulated over time and benefitted incumbent airlines. Thus, at the world’s 50 most congested airports, 67% of all flights are accounted for by the four largest airlines. This makee it difficult for the system to adapt to changing economic conditions and passenger demand.

Change, ACI World argues, will not destabilise the system. On the contrary, lack of change is the threat to the stability and growth of the network.

“Airports are ready to do the work, but we cannot build the future of aviation alone,” affirmed Erbacci. “We strongly urge airline representatives and legacy industry bodies to move past historical resistance and a ‘zero-sum’ mentality and join us in improving the slot allocation system. It is time to design a transparent, future-ready framework that unlocks operational efficiency, fosters healthy competition, and delivers the routes that the 21st century global economy demands.”