There are winds and waves in the sea, and they are changed frequently in accordance with the weather. By analyzing them which have the closest relation to the ship's safe voyage, evaluating the seakeeping performance and then taking a proper action, navigators should carry out safe navigation on the sea.
The seakeeping performance can be defined as the ability of a ship to go to sea without any loss of performance, and successfully and safely execute her missions even in inclement weather conditions.
A ship in seaways suffers continuous disturbances by irregular waves, and ship motions with irregular waves cannot be easily described as a system model which is adequate to a control system. But, in general, for seakeeping analysis, ship motions in irregular seas can be estimated by the superposition of the motion responses in regular wave components of the sea spectrum.
After comparing and analyzing the winds and waves in major sea areas, this paper evaluates the navigational safety of ships on the Korean coast with potential dangerous seakeeping performance using the weather information provided by land.
The conclusion is as follows:
(1) It is possible that the safety of ships could be secured more accurately by evaluating the seakeeping performance of ships.
(2) When the weather is bad, the departure of ships could be controlled by evaluating the navigational safety of ships.
(3) When a ship is placed in commission in any area, this evaluation could be used to decide the type and size of ship in use.