Airports where airline demand exceeds the capability of the airport require a level of coordination to manage demand. Planned flight times are adjusted so demand remains within airline and passenger service level expectations.
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Levels of Coordination
Airports are categorized according to the level of demand/supply imbalance. Different airport coordination principles and procedures apply at the different levels.
Level 1
- The airport capability is generally adequate to meet demand.
- No airport coordination is required at a Level 1 airport.
Level 2
- An airport where there is potential for congestion during some periods of the day, week, or season.
- Schedule adjustments are mutually agreed with the airlines.
Level 3
- An airport where demand significantly exceeds the airport capability.
- It is necessary for all airlines and other aircraft operators to have a slot allocated by an independent slot coordinator to arrive or depart at the airport.
Which airports are coordinated?
There are about 160+ Level 2 airports and 200+ Level 3 airports globally as published in the Contact list for Level 2 and Level 3 airports.
About 50% of all passengers depart from a Level 3 airport and around 35% of all flights operate between two Level 3 airports. Airline scheduling is therefore highly complex, constrained by a lack of airport capacity, and reliant upon the standard airport procedures detailed in the Worldwide Airport Slot Guidelines (WASG).
How are airport slots allocated?
Airport slots are allocated by a coordinator according to industry agreed principles contained in the WASG. All coordinated airports complete the coordination process according to a Calendar of Coordination Activities. This facilitates a sequential allocation of slots at both ends of a route and across airline networks, ensuring efficient network connectivity and reliability of service.