Consideration of Information Characteristic and Conduct of Vessels in Restricted Visibility

Abstract

In restricted visibility, information concerning another vessels will be scanty. So, it is more difficult to expect effective action to avoid collision than in sight of one another. Although 1972 Regulation rules conduct of vessels in restricted visibility, it is always depending upon a correct judgement of navigation officers by radar and sound signal information. In this paper, author considered characteristics of information and conduct of vessels in restricted visibility, and investigated actual cases of ship's collision. Finding are as follows. (1) Number of cases of ship's collision is not decreased. (2) Radar look-out is not appropriate. (3) Vessels do not proceed at a safe speed. (4) Action taken to avoid collision is not sufficiently put into practice according to regulation. (5) Proper use is not made in radar observation.