Airport Slots

The allocation and use of airport’s capacity

Airport slots are specific points in time allotted for an aircraft to land or take off at an airport. Where the demand for slots at a particular airport exceeds the available supply, the airport can be considered ‘capacity-constrained’, at which time, a ‘slot allocation’ process is implemented.

The management of airport capacity and slot allocation is essential to ensure efficient access to airports’ infrastructure and resources.

ACI works with governments and regulators to ensure that, when facing congestion, airports play a leading role in the definition of their capacity, its allocation to airlines, and in monitoring its effective use.

ACI supports any measure that can improve the efficient use of limited airport capacity to the benefit of the community, airlines and airports.

Airport operators wish to promote the greatest possible efficiency in the use of their infrastructure, which implies the allocation of slots to the airlines that values them most, and will fully use them, according to the allocation outcome.

The Expert Group on Slots

In 2015, ACI created a standing Expert Group on Slots (EGS). The EGS develops worldwide airport policy on slots, acting with the ACI regions. It works to promote a paradigm change of the current allocation system whereby airport operators must play a leading role in the efficient allocation of slots to airlines as they are best placed to define airport capacity for runways (aircraft movements), terminals (passenger movements) and aprons (number of aircraft parking stands), in consultation with air traffic controllers and other appropriate stakeholders as necessary.

The Strategic Review of the Worldwide Slot Guidelines

The Worldwide Slot Guidelines (WSG) have been developed by IATA and the airline industry over the last 40 years without involving airport operators and their representative organization and without including the airport industry’s view.

ACI committed at global level to work closely with the airlines and the facilitators/slot coordinators to undertake a Strategic Review of the WSG to ensure that all stakeholders benefit from an equitable global process. This was an ACI initiative at the 39th ICAO Assembly in October 2016 and represents a first global test to improve the global slot allocation process in a fully inclusive manner. The review is an important opportunity to identify new ways to put in place a truly industry-led governance to improve the slot allocation process at global level.

Visit the Strategic Review Fact Sheet (pdf) for more information.

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