Yuji Hayashi

Evaluation on Elements of Tug Boat Handling during Ships' Berthing and Unberthing

The most important task of harbor tug boats are to support berthing /unberthing of vessels, because marine pilots use those tug boats for safe and efficient ship operation when assisting vessels’ berthing or unberthing. In Japan, the new pilotage low has been active since 2007 and included the third grade pilots which newly established. Unfortunately, they do not have enough experience of tug boat management. They are trying to study about tug boats handling in the harbor for large vessels using ship handling by navigation simulation systems. The senior pilots teach them how to use the tug boats in the ship handling simulator, too. However, the senior pilots have only the experience but do not have standard of the evaluation for management of tug boats handling. In this paper, the authors propose how to evaluate the tug boat handling for ship berthing using the new standard, which is named “Evaluation on elements for tug boat handling.” It is extracted from natural images of ship berthing at actual port named Yokohama. The new standards are consisted of three elements which are propelling power of tug boats, its direction and duration of power. The authors tried to compare the values of the three elements between actual ship handlings and ship handlings by the simulation, then confirmed their effects.