Modelling cognitive processes of experienced air traffic controllers

A model of the cognitive activities of experienced air traffic controllers is presented as an example of the challenging theoretical task to model men tal processes in a dynamic task environment. Owing to the continuous change s in the task environment and the demand for the temporal co-ordination of activities in air traffic control, the model pays special attention to the mental representation of the situation. This unit of the model plays a sali ent role in maintaining situational awareness, in anticipating future state s, and in co-ordinating simultaneously ongoing events. The assumptions abou t the mental representation of the changing task environment are discussed within the mental model approach. Its realization within the proposed model is outlined. The model has been developed on the basis of experimental res earch with air traffic controllers. Brief outlines of the experiments on in formation intake, and the mental representation as examples of the empirica l investigation are presented. In an experiment on information intake, cont rollers with different levels of experience had to control a traffic scenar io while the information on the radar screen and on the flight-strips were masked. The frequencies of unmasking showed that the controller's picture i s built up by means of a considerable reduction of information regardless o f the level of experience. However, less experienced controllers used more planning data, especially information needed for short-term anticipation. A card-sorting task was used to investigate the underlying dimensions for si tuation assessment. A measure for correspondence between classifications an d multidimensional scaling established that situation assessment is based n ot only on anticipation, but also on the evaluation of further information processing requirements. The influence of the empirical results on the mode l is discussed.