Model of air traffic in terminal area for ATFM safety analysis

Air transportation system is understood as a set of elements (pilot, aircraft, air traffic control, ground ATC devices etc.), that are related to each other. Those relations are examined to check system's possibility to fulfil air transportation tasks. The safety of the vehicles involved in the transport process is one of the most important criteria for its assessment. There are many factors which contribute to that safety, including technical reliability of the means of conveyance, traffic organisation, qualifications and abilities of people who operate the vehicles and supervise the transport process, etc. The main problem Air Traffic Services encounter during realisation of their tasks is excessive congestion of aeroplanes in the airspace. This congestion is especially well visible in terminal areas. In the paper the role of Air Traffic Flow Management (ATFM) unit in unloading this congestion and in air traffic safety was shown. Then the main steps of the method for determining airport capacity were examined. The method was used not only for calculating current airport capacity, but also for preparing some prognoses of future capacities of the airport. Probabilistic analysis of these prognoses was given. On this base some propositions of methods (algorithms) of co-operation between ATC and ATFM services were proposed.