Stability – nautical quality of a ship

Abstract

Stability – the vessel’s ability to withstand the external forces causing it to roll (turn around its longitudinal axis) or trim (difference in draft of the vessel with bow and stern), and return to equilibrium at the end of the disturbance. Equilibrium is the position with acceptable values of the angles of heel and trim (in the particular case, close to zero). A ship deviated from it seeks to return to equilibrium. That is, stability is manifested only when conditions for unbalancing appear. Stability is one of the most important seaworthiness of a ship. The stability margin is the degree of protection of the vessel from capsizing. xternal influence can be caused by a wave shock, a gust of wind, a change of course, etc. Depending on the nature of the acting forces, static and dynamic stability are distinguished. Static stability is considered under the action of static forces, that is, the applied force does not change in buoyancy. Dynamic stability is considered under the action of changing (i.e. dynamic) forces, for example, wind, sea waves, cargo displacem.