Hydrodynamic manoeuvring aspects of planing craft

To get a better insight in hydrodynamic forces and moments acting on a planing hull during a manoeuvre in the horizontal plane oscillation runs have been performed. During these tests the model was fully constrained and forced into a manoeuvring motion (pure sway, pure yaw and yaw with drift). Forces and moments were measured in six degrees of freedom. Draught, trim angle, forward speed and sway- and yaw velocity have been varied systematically. Based on the measured forces and moments a mathematical model has been formulated by performing regression analysis with the varied coefficients as input variables. Subsequently, the mathematical model has been implemented in a simulation program, which has been developed earlier to describe the motional behaviour of a planing hull in six degrees of freedom. A number of simulation runs has been performed to observe the behaviour of a planing hull. Hydrodynamic terms as added mass appear to depend on forward speed.