Upotustasoon

Upotustasoon is a Finnish technical term used in naval architecture and hydrodynamics to describe the depth to which a body is submerged in a liquid. The exact meaning depends on context, but it generally refers to the vertical distance from the water surface to a reference point on the object, such as the hull’s lowest point or a designated keel line. In stability and buoyancy calculations, the upotustasoon influences the displaced volume and the buoyant force acting on the object.

Applications include determining draft and trim under load, assessing wetted surface and hydrodynamic resistance, and evaluating offshore structures and submerged equipment. Factors that affect upotustasoon include loaded displacement, ballast, trim, hull shape, water level changes (tides, waves), and dynamic motions.

Measurement is typically in meters and uses the waterline as the reference. The term derives from upottaa (to submerge) and taso (level). In Finnish technical literature it is commonly used to describe how deeply an object sits in the water; in international contexts it may be rendered as immersion depth or submersion level.