In general, conventional vessel is turned by the reaction-force of propeller thrust that is occured from rudder plate. In case of maximum tilting angle of rudder plate (normally 35 degrees), propeller thrust is devided to the forces of pressing the rudder plate and of turning the vessel. On the other hand, the ship appllied the Z-peller has a high performance of control the derection of propeller thrust at the full of 360 degrees easily. It can operate the vessel to turn with small radious and can operate "spinning".
Some datas of example for turning operation are shown on Fig.-9. These datas show required time to turn vessel at 360 degrees and show required diameter to turn the vessel for length of ship. It is very clear the difference of performance.
