IATA is the abbreviation of International Air Transport Association, an international trade body, created some 60 years ago by a group of airlines. Today, IATA represents some 290 airlines comprising 83% of scheduled international air traffic. The head office of IATA is located in Montreal, Canada and the executive office is located in Geneva, Switzerland. Japan Airlines (JAL), All Nippon Airways (ANA), Nippon Cargo Airlines (NCA) and Japan Transocean Air (JTA) are the members of IATA in Japan.
IATA’s aim is to help airlines by simplifying processes and increasing passenger convenience while reducing costs and improving efficiency. Safety is IATA’s number one priority, and IATA’s goal is to continually improve safety standards, notably through IATA’s Operational Safety Audit (IOSA). Another main concern is to minimize the impact of air transport on environment.
IATA ensures that people and goods can move around the global airline network as easily as if they were on a single airline in a single country. IATA also seeks to improve understanding of the industry among decision makers and increase awareness of the benefits that aviation brings to national and global economies.
WASG is the abbreviation of Worldwide Airport Slot Guidelines where the policy, principle and process that airlines schedulers, coordinators and facilitators have to follow are defined. The policy, principles and process that include the role of airlines, airports, coordinators and facilitators, the priorities of coordination, and ‘Use It or Lose It’ rule, etc. are defined in this WASG. The WASG is developed and maintained by three parties; IATA, ACI (Airport Council International) and WWACG (Worldwide Airport Coordinators Group).
According to the degree of congestion, the airports are categorized into three levels as follows.
- Level 1: The airports capacities are adequate to meet the demands of users. Such airports are recognized from a schedule clearance viewpoint as non-coordinated;
- Level 2: The airports where, due to demand, a more formal level of co-operation and facilitation is required to avoid exceeding scheduling parameters. These airports are referred to as schedules facilitated;
- Level 3: The airport demand exceeds capacity during the relevant period and it is impossible to resolve the serious problems in the short term. In this scenario, formal procedures have been implemented at the airport to allocate capacity and coordinate schedules. Airports with such high levels of congestion are referred to as coordinated.
SSIM is the abbreviation of Standard Schedules Information Manual. This Manual contains an official set of Recommended Practices, which is intended to guide the aviation industry along mutually compatible lines, in the development of schedules data handling procedures.
Since the schedule coordination works are conducted among airlines schedulers, coordinators and facilitators by exchanging the flight schedule data through the internet or SITA communication network, it is essential to unify message type, message format, aircraft code, airline code and airport code.
The international flight schedules are revised twice a year for summer and winter seasons.
(1) Summer Schedule
It is 7 months from the last Sunday in March to the Saturday prior to the last Sunday in October. The northern summer scheduling season begins on the date of Daylight Saving Time (DST) introduction in European Union (EU) countries, which currently always takes place on the last Sunday in March.
(2) Winter Schedule
It is 5 months from the last Sunday in October to the Saturday prior to the last Sunday in following March. The northern winter scheduling season commences on the date DST ends in EU countries, which currently always takes place on the last Sunday in October.
The core of the slot coordination process is the use of historical precedence. This precedence applies only to equivalent, and not to consecutive scheduling periods (e.g. Summer to Summer scheduling periods), and is limited to the equivalent period and days of operation. This principle entitles an airline to claim a series of slots within the same coordination parameter in the next equivalent scheduling period, provided that at least 80% of the slots were operated by the airline as cleared by the coordinator.
The U/L rule is the abbreviation of ‘Use it or Lose it’. A series of slots which have been allocated to an airline will not be granted historic precedence in the next equivalent scheduling period, unless the airline can demonstrate to the satisfaction of the coordinator, that they have been operated, as cleared by the coordinator, for at least 80% of the time during the period for which they have been allocated.
IATA has developed a process for schedules coordination and slot allocation through the IATA Slot Conferences, which are held bi-annually. At this conference, over 85 coordinators and facilitators at busy airports designated by IATA and over 230 schedulers from IATA and non-IATA airlines get together to coordinate their planned seasonal schedules with respect to declared airport capacity limitations.
(1) SC153 (to be held in November 2023, in Dubai, United Arab Emirates)
(2) SC154 (to be held in June 2024, in the Americas)