Maneuvering Performance of Indonesian Ro-Ro Ferries under Action

Maneuvering performance is one of the most important aspect in ship operation especially when the ship operating in rough weather. Ships with large windage area may have large drift angle. In order to maintain the ship direction or heading angle, a significant rudder angle is necessary. The ship speed may significantly decreases due to high wind speed. This paper discusses maneuvering performance of Indonesian ro-ro ferries under action of variation wind speed. The wind speed variation was determined using the ratio between the wind speed and the ship speed. The wind direction is also simulated from 0 degree (head wind) and 180 degrees (following wind). The results show that the drift angle significantly increases due to increases the wind speed. The maximum drift angle occurs when the angle of wind direction relative to the ship is 60 degrees. The same phenomena occur in case of the rudder angle. However the necessary rudder angle in order to maintain the ship direction is larger than the drift angle of the ship mainly in low wind spee