Maximum righting arm

The maximum righting arm is the peak value of GZ on the righting-arm curve, the largest restoring lever the ship can develop and a direct measure of its reserve against capsize. The IMO 2008 IS Code requires the maximum GZ to occur at a heel of at least 25 degrees, preferably 30 degrees or more, and the righting arm at 30 degrees to be at least 0.20 m. Multiplied by displacement it gives the maximum righting moment. The angle at which it occurs and the area beyond it set the dynamic stability available to absorb a gust or wave energy. A peak occurring at too small an angle signals a tender or marginally stable condition.