Which factor primarily dictates a vessel’s righting ability in case of a capsize?

The primary factor that dictates a vessel's righting ability in the case of a capsize is the distance between the center of gravity and the center of buoyancy. This distance plays a crucial role in determining the righting moment, which is the force exerted on the vessel to return it to an upright position.

When a vessel heels over due to external forces, the center of gravity (the point where the vessel's weight is concentrated) shifts, and the center of buoyancy (the point where the weight of the water displaced by the hull acts) also moves. The larger the horizontal distance between these two centers, the greater the righting moment produced. Essentially, if the center of buoyancy is significantly higher than the center of gravity when the vessel is heeled, the vessel will have a stronger tendency to return to an upright position.

While the weight of the crew, the shape of the hull, and weather conditions can all influence stability and performance, it is fundamentally this distance between the centers that affects the righting arm and thus the vessel’s ability to recover after capsizing. A well-balanced vessel with a low center of gravity and high center of buoyancy optimally maximizes its righting ability.