It means the approximate formulae for hydrodynamic derivatives shown in Equation (7) can express sufficiently manoeuvring characteristics depending on aft hull shape.

　

 Fig. 8 - Fig.11 represent comparison of simulated and measured results in 10/10 & 20/20 zigzag manoeuvre. Results for Ship A with scantling draft condition are shown in Fig.8 and Ship A with heavy ballast condition is shown in Fig.9. Ship K with ballast 1% trim condition are shown in Fig. 10 and Ship K with ballast 2% trim condition are shown in Fig.11. There seems good agreement between predicted and measured results. This means the new approximate formulae can express change of loading condition in zigzag motion.

　

 Fig.12 - Fig.15 show time histories of the normal force acting on rudder F'N in zigzag motion. Results for Ship B with full load condition at 20/20 zigzag test are shown in Fig.12, Ship J with full load condition at 10/10 zigzag test is shown in Fig.13.