Select Committee on European Communities Minutes of Evidence

Memorandum by Airport Coordination Limited


  The IATA Scheduling Procedures Guide provides the framework for slot allocation for all Coordinators world-wide and sets the timetable of events in the scheduling process.

  The coordination process at all UK airports is consistent with the IATA guidelines.

  The guidelines are, of necessity, broadly framed to allow the unique problems at each airport to be resolved locally by the Coordinator in a flexible manner acceptable to the airlines, the Airport Operator and the Authorities, e.g., HM Customs.

  The process used by each Coordinator to resolve the scheduling problems at their airports varies widely. The approach may even vary from season to season.

  The process is driven by the dynamics of changing capacity/demand, IATA guidelines. Regulations (National or EU), local rules and the availability of technology, time, resources, etc.

  It is therefore impossible to be prescriptive about the process and criteria but the details below give a broad outline.


  A "slot" is the scheduled time of arrival or departure available or allocated to an aircraft movement on a specified date at an airport.


  1. Day to day schedule changes by airlines throughout each season are evaluated by the Coordinator and processed as either an ad hoc, a temporary change to an historic schedule, or a permanent change to the historic schedule.

  2. In September each year, what the Coordinator considers to be the Summer historic schedule is sent to each airline for checking. This ensures any disagreements between the airline and the Coordinator can be resolved before the schedule submissions for the next Summer season in October. (Winter historics are established in April before schedule submissions in May).

  The historic schedule is based upon the results of the slot monitoring process undertaken by the coordinator throughout that season. Clarity about the historic baseline is then established before the submissions are received from the airlines by the Coordinator.

  3. The scheduling limits (runway, terminals, stands etc.) are normally negotiated with the Airport Operator control authorities and the airlines around the same time that the historic schedule is sent out.

  Agreement is normally reached on the scheduling limits, and the constraints associated with them, to be applied by the Coordinator shortly before the submission deadline.


  1. Airline schedule requests are submitted to the Coordinators by midnight on the schedule submissions deadline set by IATA. This is normally in May for Winter season and in October for a Summer season. This produces a picture of "Raw Demand" (unconstrained demand) for the airport and for the Coordinator.

  2. Prior to any slot allocation decisions the schedule data which has been submitted by the airlines is generally sorted into one of four categories:

    (i)  Historic Slots—there is some flexibility here as some changes are allowed which do not materially effect coordination parameters e.g., flight number change. More significantly changes which may have capacity implications, e.g., substitution of a larger aircraft, timing adjustment etc. are put into the second group called Changed Historics.

    (ii)  Changed Historics—these are flights for which the airline already holds an historic slot but which, for a variety of operational or commercial reasons, have been requested at a different timing, or with a larger aircraft etc.

    (iii)  New Entrants—the new entrant group of schedules is further subdivided between new airlines to the airport and new services requested by incumbent airlines but qualifying under the "no more than four slots on a day" or "intra-community route" criteria in the IATA Guidelines and EC Regulations.

    (iv)  New Incumbents—these are all new slot requests by existing operators not qualifying as new entrants.

  3. Initially, all Historic Slots and Changed Historic slots are put into the new seasonal database.

  4. Changed Historics which breach the scheduling limits are rescheduled as close to their required time as possible but within the scheduling limits.

  5. The net result of this process, which takes a numbr of days, is a fully coordinated airport within all the scheduling limits but based entirely on Historic and Changed Historic schedules. Approximately 10 per cent of airlines historic schedules are changed each season. Schedule adjustments by the Coordinator to meet scheduling limits have been minimised.


  1. Once Historic and Changed Historic schedules have been accommodated any new capacity is added to the process. New capacity may arise from higher scheduling limits, historic slots no longer required by carriers and slots lost under use-it-or-lose-it rules. This provides the pool of slots available for allocation to new requests.

  2. The allocation of new slots then begins—up to 50 per cent of the new capacity is allocated to new entrants both new to the airport and qualified new entrants with the remaining 50 per cent being allocated to new requests by incumbent carriers. If the 50 per cent available to new entrants is not fully subscribed, the remaining slots are also allocated to new flights by incumbent operators.

  Slots are considered by the Coordinator on a day by day hour by hour basis. For each hour that slots are available the Coordinator considers which airlines are requesting slots, i.e., who is on the "waiting list".

  The feasibility of each allocation decision is tested by adding the selected flight to the Coordinator's computer database which contains a mathematical model of airport capacity and scheduling limits. No flights are added which break scheduling limits.

  3. The criteria used in the allocation decision process are summarised below and are the same for new entrants and incumbent operators.

    (a)  Primary Criteria

      —  Historical precedence

      —  Schedule change

      —  New Entrants

      —  Introduction of Year—Round services

      —  Effective Period of Operation

      —  Joint Operations

    (b)  Secondary Criteria

      —  Size and Type of Market served

      —  Competitive requirements

      —  World-wide scheduling constraints e.g., curfews

      —  Needs of the travelling public

      —  Frequency of operation

  Other criteria which are taken into consideration at UK Airports are:

      —  Night Flying Restrictions

      —  Effect of Traffic Distribution Rules e.g., peak hours

      —  Bilateral issues e.g. frequencies allowed on route

      —  Licensing issues

      —  Minimising stand usage

      —  Airlines which have applied for a particular slot in previous seasons (seasonal waiting list)

      —  "Sharing out" the limited available capacity between the carriers

      —  Ad-hocs; Trade fairs etc. are given lower priority

  4. A large number of slots remain available even at the end of the coordination process though the number is diminishing at many airports. This is because some slots are commercially unattractive.


  Following the coordination process, listings are produced for each airline showing the slots requested and the slots offered and, where there is any variance, the reasons for the change are shown.

  These listings, and many like them, are distributed by Coordinators to the airlines on the first day of the IATA Schedule Coordination Conference which is held twice a year in June (for Winter seasons) and November (for Summer seasons).


  The objective of the IATA Conference is to agree the slot allocations for the coming season between airlines and Coordinators for airports around the world.

  The airlines attending have other objectives such as optimising connections and ground handling arrangements.

  The Conference is attended by airlines and Coordinators and up to 650 delegates may attend.

  Some airlines and Coordinators set up a sophisticated operation (i.e., office, computer systems, staff, etc.) and some are quite unsophisticated.

  The process of the Conference is for airlines to make brief appointments to see the Coordinators of the airports they plan to serve in the coming season and then to meet and discuss/agree the feasibility of the proposed schedule.

  Airlines engage in slot exchanges with one another in order to improve the slots which they hold.


  The dialogue between the Coordinator and the airlines on scheduling matters continues long after the IATA Conference and into the operating season as the airlines add, change and delete their flights as changes by one airline may release slots which can benefit other airlines.

  In the period after the Conference, many airlines engage in slot exchanges in order to improve the slots which they hold.



  1. A system for managing the imbalances between airline demand and airport capacity has been developed over many years under the auspices of IATA through a process of schedule coordination and slot allocation.

  2. In most countries, though not all, this work is undertaken by the "national" carrier or the largest operator at each airport, e.g., Olympic Airways takes responsibility for slot allocation at all Greek airports.

  3. In the UK British Airways (BA) held responsibility for slot allocation at Heathrow, Gatwick, Manchester and Birmingham at the request of the airlines serving these airports.

  Within BA a "chinese wall" existed between the coordination team responsible for slot allocation and the rest of BA to ensure the necessary neutrality.

  4. The criteria used for decisions on slot allocation are those laid down by IATA combined with a complex set of UK and European Regulations.

  5. For many years the Airport Operators at each coordinated airport (e.g., HAL at Heathrow) made a financial contribution to BA towards the cost of providing the coordination service and a contractual relationship existed between the Airport Operators and BA.

  6. In the late 1980's the European Commission (EC) became interested in the slot allocation system for two primary reasons:

    (i)  The Commission was concerned about bias in slot allocation decisions in some countries.

    (ii)  The slot allocation system was perceived as a significant obstacle to the liberalisation of air transport, particularly after the introduction of the Single European Market.

  7. In 1991 BA decided to change its relationship with the coordination team in BA and formed a separate subsidiary company, Airport Coordination Limited (ACL), to take over BA's responsibilities for slot allocation.

  The primary objectives were:

    —  To increase the perceived neutrality of the coordination process.

    —  To reduce the need for regulatory intervention by the EC.

    —  To broaden the participation in the UK slot allocation system.

Airport Coordination Limited

  1. Throughout 1991 BA negotiated with eight other airlines about the structure and ownership of ACL.

  The Airport Operators, the CAA, the Department of the Environment, Transport and the Regions and the European Commission were also consulted.

  2. Airport Coordination Limited was re-established as an independent company Limited by Guarantee and jointly owned by nine UK airlines on 27 May 1992.

  Since 1992 airline membership of ACL has grown to 11 airlines.

  These 11 airlines make a financial contribution towards ACL's running costs without any involvement in the slot allocation decisions which are made by Coordinators appointed by ACL.

  3. Membership of ACL is "open to all those Airlines who from time to time express an interest in the allocation of slots" at UK airports.

  4. ACL is an administrative organisation primarily responsible for the delivery of data collection, schedule coordination or, slot allocation services under contract (Coordination Agreements) to Airport Operators and has no policy making role.

  The Coordination Agreements lay down performance standards.

  ACL receives funding from the Airport Operators which contributes towards ACL's running costs.

  5. ACL now serves 12 airports, Heathrow, Gatwick, Manchester, Birmingham, Luton, Glasgow, Edinburgh, Aberdeen, Stansted, Newcastle, London City and Jersey.

  6. A slot Regulation was finally introduced in January 1993 as EC Regulation 95/93 on the allocation of slots at Community airports with the objective of increasing transparency and neutrality of the scheduling process, to avoid discrimination between operators and to provide opportunities for new entrants.

  ACL meets all these objectives.

  7. The EC Regulation was followed by the introduction of a UK Statutory Instrument 1993 No. 1067 in May 1993 which brought the EC Regulation into UK law.

  ACL has now been formally appointed by the Airport Operators and approved by the Secretary of State for Transport to be responsible for schedule coordination and slot allocation at most major airports in the UK.


  1. The Airline Scheduling Committees have existed in the UK for many years.

  2. Each Scheduling Committee is an un-incorporated association and is the representative body for all the Airline Operators having expressed an interest in the allocation of slots and coordination of schedules at a particular airport.

  Each Committee is responsible for developing, within the IATA Guidelines, local scheduling guidelines and advising the Coordinator. Local guidelines may be necessary for scheduling issues not covered by the IATA Guidelines, e.g., administration of night noise quotas.

  3. As an example the Constitution of the Heathrow Scheduling Committee shows its purpose to be:

    (a)  to formulate scheduling policies and guidelines specific to Heathrow;

    (b)  to advise the Coordinator in connection with the efficient allocation of slots and coordination of schedules at Heathrow; and

    (c)  to represent the views of Heathrow Operators on scheduling matters.

    (d)  To negotiate reductions in constraints on capacity on behalf of all Heathrow Operators and promote improvements in the utilisation of facilities.

    (e)  To solve by mediation problems involving conflicting demands for slots.

The Scheduling Committee has no responsibility for the allocation of slots.

  4. To overcome the logistical difficulties of large meetings, each Scheduling Committee elects a representative Executive Committee to undertake the work of the Scheduling Committee.

  5. Members of the Scheduling Committee participate in the Coordination Committee as the airlines' representatives.


  1. EC Regulation 95/93 requires the formation of a Coordination Committee (Article 5) at fully coordinated airports (Heathrow, Gatwick and Manchester in the UK).

  2. Membership of the Coordination Committees includes airlines, the Airport Operator, Air Traffic Control and General/Business Aviation representatives.

  3. The role of the Coordination Committee is, inter-alia, to advise the Coordinator (ACL) on such matters as increasing airport capacity, methods for monitoring the use of allocated slots, local guidelines for slot allocation, etc.

  4. The Coordination Committee can also deal with any complaints on the allocation of slots or problems experienced by new entrants in obtaining slots which are referred to it by the airlines or the Scheduling Committee.


  1. The Airport Operator (e.g., HAL at Heathrow) has the ultimate statutory authority for the allocation of slots at the airport under the Airports Act 1986.

  2. The Airport Operator at each airport has signed a service contract (Coordination Agreement) with ACL for the provision of a Coordination Service.

  3. The Airports agree to "ratify all acts, deeds and things done by ACL in the course of and whilst acting within the terms of ACL's appointment".

  The terms of appointment specify that ACL will carry out its function "in accordance with guidelines issued by the International Air Transport Association (IATA) to best industry standards and in accordance with all applicable laws and regulations and properly formulated and adopted IATA and Scheduling Committee guidelines".

  4. The scheduling limitations of airport facilities are negotiated and agreed with the Airport Operators e.g., Runways, Terminals, Stands etc., usually twice each year. ACL agrees to use all reasonable endeavours to meet the scheduling limits set by the Airport Operators.

  5. ACL provides schedule data to the Airport Operators electronically on a regular basis with details of airline schedules based on allocated slots.


  1. The European Commission has taken a keen interest in the allocation of slots at Community Airports since 1989.

  2. The EC introduced a Block Exemption for the allocation of slots at Community Airports to provide an exemption under Articles 85 and 86 of the Treaty of Rome subject to certain conditions e.g., the neutrality and transparency of the slot allocation process.

  The Block Exemption is due for renewal in 1998.

  3. In January 1993, after extensive industry consultation, the EC introduced EC Regulation 95/93 on the common rules for the allocation of slots at Community airports.

  4. There have been a number of reviews of the working of the existing Regulation and the industry has been consulted on early drafts of a replacement Regulation which the EC is intending to introduce.


  1. The Civil Aviation Authority and Department of the Environment, Transport and Regions maintain an arms length relationship with ACL and have no direct involvement in the slot allocation process.

  2. However Regulations, such as the Night Noise Restrictions, continue to influence the priorities for slot allocation in the UK.

  3. The UK Statutory Instrument 1993 No. 1067 (The Airports Slot Allocation Regulations 1993) gives effect in UK law to the EC Regulation 95/93 on common rules for the allocation of slots at Community airports.

  4. The Civil Aviation Authority informally monitors ACL's performance and has produced a number of reports on the results of ACL's slot allocation decisions.


  1. The voluntary IATA system for the allocation of slots and coordination of schedules continues to provide the world-wide framework for slot allocation.

  2. IATA Conferences are held twice each year and revisions to the principles, practices and priorities of slot allocation are discussed by the airline industry and the guidelines are changed when consensus is achieved.

  3. The most fundamental principle of the IATA system is that of "historic precedence". This principle has been recognised and endorsed in EC Slot Regulation 95/93.

11 February 1998

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