||The paper presents the development of a new simulation method to optimize bends in marine waterways. This
method, using results of empirical research and simulation methods, would allow accurate determination of
safe manoeuvring areas. The method was used at the stage of detailed design of parameters of the, which is
undergoing modernization, to determine the optimum parameters of horizontal curves of the fairway. The study
was conducted on the type of manoeuvring simulator called Polaris Kongsberg and attended by pilots from the
Szczecin–Swinoujscie Pilot Station. Based on the studies carried out, the maximum safe ship length was determined
for the redesigned waterway and the conditions for their safe operation. The maximum lengths of these
ships are as follows: cruise Lc = 260 m, container Lc = 240 m and a bulk carrier Lc = 220 m.