Reducing GHG emissions is an urgent issue in the maritime industry. One of the effective measures is to increase the size of the ship. Here, such a ship is called a full ship. A full ship can reduce the fuel consumption per unit cargo, which subsequently can contribute to reducing the GHG emissions. However, the problem with full ships is their course instability. When maneuvering within a small range of rudder angle, a ship which has the course instability responds differently from the one that the helmsman intended. This significantly lowers the course-keeping ability, which may lead to inefficient maneuvering. Thus, in regard to GHG emissions reduction, it is important to consider the course instability of full ships. In this study, we analyzed the turning characteristics of a VLCC from the actual voyage data. We also conduct simulations based on MMG model to reproduce the turning characteristics of the ship.
Moreover, the effect of course instability during some course-changing tests in a real sea is also discussed.
