With the onset of congestion during some periods of the day at a few major airports in the early 1960’s, the scope of the schedule discussions was broadened to cover the adjustments needed to reduce anticipated delays to an acceptable level. Where services planned during certain periods at an airport exceeded what the airport could accommodate without unacceptable delays, some services would have to be moved, usually with some economic penalty. This induced IATA (International Air Transport Association) to establish coordination offices at such airports, usually embedded within the organisation of the national airline. Over the years, a consensus developed as to which services should be moved, in fairness to all planning to operate during the period. The recommended procedures and priorities for such schedule adjustments are contained in the Worldwide Airport Slot Guidelines (WASG), first issued by IATA in 1976.

Airport Coordination

Airport coordination is a means of managing airport capacity through the application of a set of rules contained in the Worldwide Airport Slot Guidelines (WASG). Coordination involves the allocation of constrained or limited airport capacity to airlines and other aircraft operators to ensure a viable airport and air transport operation. Coordination is also a process to maximize the efficient use of airport infrastructure.
The prime objective of airport coordination is to ensure the most efficient use of airport infrastructure in order to maximize benefits to the greatest number of airport users.

For the purposes of airport coordination, airports are categorized by the responsible authorities according to the following levels of congestion:

• Level 1: airports where the capacity of the airport infrastructure is generally adequate to meet the demands of airport users at all times.
• Level 2: airports where there is potential for congestion during some periods of the day, week, or season which can be resolved by voluntary cooperation between airlines. A facilitator is appointed to facilitate the planned operations of airlines using or planning to use the airport.
• Level 3: airports where capacity providers have not develop sufficient infrastructure, or where governments have imposed conditions that make it impossible to meet demand. A coordinator is appointed to allocate slots to airlines and other aircraft operators using or planning to use the airport as a means of managing the declared capacity.

source: Worldwide Airport Slot Guidelines para 1.4

Airport Coordinator

A coordinator is appointed by the responsible authority, following consultations with the airport managing body, all airlines using the airport and their representative organizations. Coordinators must be functionally and financially independent of any single interested party and act in a neutral, transparent and non-discriminatory way.

source: Worldwide Airport Slot Guidelines para 5.2

Within the European Union the airport/schedule coordination shall be established and operated as independent entity acting according to the Regulation (EEC) 95/93 which came in force 1993.

Visit also the website of the European Union Airport Coordinators Association.