On the manoeuvring performance of a ship with theparameter of loading condition

On the prediction of ship manoeuvring performance at the initial design stage, it is considered that a loading condition is one of the important parameters caused for the manoeuvring characteristics. For the prediction of ship manoeuvrability with high accuracy, it will be required to estimate the hydrodynamic forces acting on ship accurately in any loading conditions.In this paper, the approximate formulae for estimating the hydrodynamic forces acting on ship in any loading conditions such as half loaded, ballast and trim by stern conditions are proposed. These approximate formulae were derived from the results of model test. The model ships used for obtaining the hydrodynamic forces are 13 ships consisting of general cargo, car carrier and RORO ships. And the model test was carried on 13 ships for fully loaded condition, on 11 ships for ballast condition and 5 ships for half loaded condition.By comparing with the measured results of free running model test, the prediction results agree well with model test results. Therefore, this method will be useful for practical prediction of manoeuvrability for conventional ship at the initial design stage. However since those approximate formulae have been investigated on model ship, there still remain some problems to be solved such as a correlation, scale effect and so on, to predict the manoeuvring performance of full scale ship.