It is increasingly important for ship owners and ship builders to study the ship service performance under seaway in order to check their design considerations and to make the economic evaluations precisely for their ships. For this purpose, the analysis of the ship service performance should be performed on such standardized method that is suitable to compare the analyzed results with each other and is able to apply them to the new ships under design. The authors developed a new analyzing system of the ship service performance which matches the above demands sufficiently. In this system, the fouling and the aging effects are obtained in the form of increment of correlation factors, i.e., the increment on roughness effect δΔC_f and that on wake fraction δe_i, from the abstracted log book data, and other elements which affect ship's performance under seaway, for examples, wave and current effects, are also obtained analytically. Furthermore, the evaluation of the service performance on a given ship becomes possible by the use of above correlation data. The computer program for the system has been completed. As an example, the service performances of a cargo liner and a bulk carrier are analyzed by the use of this newly developed system.
