Assessment of the safety level of a ships passing manoeuvre in the fairway

Safe two-way vessel traffic may have some limitations. Fairway width, vessel dimensions, weather conditions, traffic density and other factors must be considered crucial and constraining safe passage of the vessel. The possible sea traffic regulation made by a Vessel Traffic Service (VTS) shore centre, is often based on criteria included in harbour regulations. This may not always be an optimum solution. This paper presents a concept and elements of a method for assessment of safe two-way traffic, based on experts' (pilots') knowledge and experience. The goal is to support the decision making process in a VTS centre. For this purpose tools of knowledge acquisition and representation as well as tools of statistical inference are used. The method is based on the results of the expert research which was performed with the participation of pilots who handle vessels on the Świnoujście-Szczecin fairway.