The aim of this paper is to provide a simple method for the definition of a rudder for tuna purse seiners.The model achieved by the application of this method ensures the manoeuvrability of initial turning,course keeping and yaw checking. For this, the results obtained by other authors, through rudder tests andmanoeuvrability tests of fishing vessels have been integrated with the recommendations of the InternationalNormative. Finally, in the paper the method is applied to the case of a tuna vessel, providing a rudder modelwhich could be optimised with CFD (Computer Fluid Dynamics) in further tests. The method proposedcan be applied to other vessels whose main dimensions are met.
