Unconventional Rudders

Conventional rudders do not provide adequate manoeuvrability for some ships. Such ships may have unconventional rudders. This chapter describes the special features of these rudders, their advantages and disadvantages and methods to determine their performance. Among the rudders considered here are rudders with tail-wedge and fishtail sections, Schilling rudder, Pleuger active rudder, flap rudder and some other unconventional rudders. Modern developments including the Vectwin rudder and the Gate rudder are included. Modifications of the MMG model for simulation of manoeuvring of ships with these types of rudder are discussed.