Abstract
Many studies related to port planning focus on the difficulty of steering ships using simulators in winds or currents. In addition, there are many studies on moored ship motions caused by long period waves. These, too, are related to harbour construction and operation. On the other hand, the safety of the entering harbour is researched on ship motions of small ships under wind waves. It is cleared that operators are challenged by ship motions as they enter harbours. However, there is no detailed research on large ships subjected to swells and waves produced by typhoon winds in the Pacific Ocean. In this study, the focus is on an operational problem of a 12, 000 DWT class ferry as it enters and departs a southern Japanese harbour facing the Pacific Ocean. Firstly, the hearing researches are carried out to captains of the ferry line. Field observations are carried out using a new method of observing ship motion. Two problems contribute to the difficulty of steering a ship in swells. A rolling motion occurs inside the harbour, which makes the berthing operation very difficult when a ship approaches the terminal. Finally, we analyze these observed data and consider the new problem of the ship operation at harbours facing to the Pacific Ocean.
