心理学からみた衝突海難における操船情報処理上の問題点

抄録

For the purpose of investigating skills in ship manoeuvring work, many field researches were made by us. Verbal communication among navigation staff was analyzed by clasification according to content and function and by drawing sequential diagrams. And verbal communication proved to play a vital role in ship manoeuvring work by decreasing uncertainty and indeterminacy of relevant informations. Also it was found that inferrings which we often observed in their communication have very important role to make a decision under the circumstance that they cannot obtain certain information to manoeuvre their ships in safety. As it become more hard to operate their ships at night, the role of inferrings become more important. About 30% of messages were questions, confirmations, reconfirmations, or inferrings as to the existence, distance, and direction of other ships, including many uncertain expression.
According to our other data of changes in heart rates of ship manoeuvrers while they were manoeuvring their ships in narrow channels and harbours, it was found that their heart rates came upto 110, 120, and sometimes nearly 140 beats per minute. The results of nearly 100 cases studies showed significant changes in their heart rates when; (1) there was a need of more information to maneuvre the ship; (2) the needed information to manoeuvre the ship was not obtained; (3) important decisions were made by the manoeuvre. As the physical movements of manoeuvrers were limited and as the changes in the heart rate corresponded well with conditions of their ships, these observed changes in their heart rates could be attributed to mental strain. Therefore, it is clear that ship manoeuvrers, are now under the circumstance that are obliged to maintain safety and security and to ensure ships against sea hazards under extreme conditions without certain informations with very poor manoeubrability of ships.
In the other hand, when we analyse relevant laws and regulations and judicial precedents of Maritime Court from psychological aspects, it become clear that they are thinking most of disasters and accidents were caused by faults and negligences of ship manoeuvrers and that they do not pay attention to said circumstances.
We are thinking it is urgend need to understand and realize (1) skills of works, (2) possibility of engineering, (3) content and meanings of relevant laws and regulations. And it shoud be pointed here that we have to develop the study to improve mutual relations among mentioned three factors. Otherwise, we cannot decrease disasters and accidents not only at sea but also on land.