What does "K" refer to in stability calculations?

In stability calculations, "K" refers to the distance from the baseline to the waterline, known as the vertical center of buoyancy. This measurement is crucial for determining the stability of a vessel because it helps establish the relationship between the center of gravity (G) and the center of buoyancy (B). The stability of the vessel is affected by these distances, as the metacentric height (GM) is a key factor in assessing how a vessel will respond to heeling or rolling.

By including "K" in the calculations, naval architects and ship engineers can evaluate the righting arm, which is the distance between the center of gravity and the center of buoyancy, and thus predict how well the vessel will return to an upright position after being tilted. The stability of a vessel is fundamentally dependent on this vertical distance, which directly influences the vessel's overall performance at sea.

Understanding "K" is essential for ensuring that a vessel is designed and operated within safe stability limits, preventing capsizing and maintaining safety for the crew and cargo.