Instruments and Systems: Monitoring, Control, and Diagnostics Annotation << Back Model of function of the control tower of air traffic control system determined by critical state of air traffic controller I.N. SHESTAKOV The controller’s qualification affects all the processes that take place in the air traffic control system (ATC) and actually determines the functioning of the control tower (CT) model. The increase of the air traffic intensity is limited by the controller’s critical state in which he cannot provide the demanded level of safety. Such state is equivalent to the notion of congestion queuing in the ATC system, which is used in the theory of queuing systems. In this paper we describe the CT models for the ATC system that depend on the controller’s qualification. The conditions of the ATC system congestion queuing and of the collision risk are defined on the base of the given analysis. The general scheme of the CT functioning is provided. The conditions of failure of the ATC system and the risk of collision, when it is an air traffic controller limiting condition characterized by the maximum number of aircraft while under his management. It is shown that the intensity of air traffic (stream of requests for service) and an air traffic controller qualifications define the schema functioning CT. Keywords: air traffic controller, control tower, air traffic control system, flight safety, queuing systems, system with failures, collision risk. Contacts: E-mail: shin63@mail.ru Pp. 01-04.