摘要:This report deals with the stability of ships having comparatively large projected lateral area above water line and shallow draft. Such ships usually have wide breadth because they have tendency to raise their center of gravity. Large GM made by the wide breadth brings strong stability. But it gets weaker if the ship has higher center of gravity because GM/(OG+T/2) becomes smaller. A research challenge of this report consists of the procedure to clarify the acceptable center of gravity and how breadth and draft to be examined and determined. These procedures enable the optimization method in the initial design. In the analysis, the metacenter is estimated by Ohgushi’s and Morish’s formula and the accuracy of the estimation is confirmed using merchant ships’ data released for public. The present method obtained by the analysis shows effectiveness to find out reasonable dimensions and acceptable height of center of gravity in the early stage of ship design.