The effect of voluntary speed reduction criteria on attainable ship speed

Another important manoeuvre in rough seas is the speed reduction. This action is not dependent on the ship size (Guedes Soares, 1990). The reasons for speed reduction may generally be divided into two categories:

− natural reasons, such as the added resistance due to wind, waves and current, steering, change of wake field and loss of thrust (Faltinsen, 2005).