The paper deals with the formulation and analysis of the problem of ship's traffic control in separation schemes. The branch and bound procedure has been used for optimal solution of the problem. The proof for a possible computational process is given together with the results of a numerical example.

In view of the rapid development of the world merchant fleet the problem of safety at sea appears now as neither fully defined nor sufficiently analysed. Some measures and partial solutions to improve the safety of sea traffic have been suggested and implemented, e.g. in papers by Ciletti and Glas. As examples of such implementation one can mention traffic lanes, the calculation of separation-scheme optimal crossing angles, etc. In areas with heavy traffic where either natural constraints such as islands, submerged obstacles or traditional routes exist, all the separation lanes create sophisticated systems called traffic separation schemes. Many steps now being taken to improve safety of navigation are based essentially on traffic separation. Some innovations and improvements in designing the structures of the separation schemes must be taken into account. It seems that all such passive measures will be efficient up to natural limits connected with the magnitude of the traffic flow. In heavy traffic the author believes active control should be established.