When overtaking in a narrow channel, it should be avoided if possible due to the danger involved. If it is executed, both ships must be aware of the situation and carry out the correct maneuvers on the rudder in time. The overtaken ship may go out of control due to her reduced speed and lesser rudder effectiveness.
The distance between the ships must be considered dangerous, and distances under a ship’s breadth should be avoided. The closer the ships are, the larger the effects will be on the overtaken ship.
If the two ships are making almost the same speed, there is enough time to counteract the turning moments. If the difference in speeds is large, the effects will change quickly and the ships will not have time to go into a noticeable turn. Differences in speeds of 20-30% are especially dangerous.
A quick overtaking should be aimed for, especially at a large difference in speed.
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