In order to make sure the vessel hits its planned course track after a major course alteration, it is adviseable to calculate and plan the turn in advance. This is especially valid for larger vessels. With this method a safe and controlled turn can be carried out.
This method requires that the vessel is equipped with a Rate of Turn indicator.
The Rate Of Turn can be found with this approximate formulae: ROT (0/min) »
(The ROT is measured in “degrees per minute” )
- Select the turn radius. (In this example: 1 nautical mile)
- Construct the turn in the charts with the selected turn radius to find the Centre Of turn.
- A line drawn from the Centre Of Turn and 900 down to the initial course track marks the Actual Start Of Turn.
- The position of the Wheel Over Line is generally, for larger vessels, about 1-2 cables before the Actual Start Of Turn The Wheel Over Line should be drawn parallel to final planned course track.