Aninclining test is a test performed on aship to determine itsstability, lightship weight and the coordinates of itscenter of gravity. The test is applied to newly constructed ships greater than 24 metres (79 ft) in length, and to ships altered in ways that could affect stability. Inclining test procedures[1] are specified by theInternational Maritime Organization and other international associations.
The weight of a vessel can be readily determined by readingdraughts and comparing with the known hydrostatic properties. Themetacentric height (GM), which dominates stability, can be estimated from the design, but an accurate value must be determined by an inclining test.
The inclining test is usually done inshore in calm weather, in still water, and free of mooring restraints to achieve accuracy. The GM position is determined by moving weights transversely to produce a known overturning moment in the range of 1-4 degrees if possible.[2] Knowing the restoring properties (buoyancy) of the vessel from its dimensions and floating position and measuring the equilibrium angle of the weighted vessel, the GM can be calculated.
As in a new ship test, the weight shifts have to be known and the angles of list measured. A series of weight (ballast) movements are used to obtain an average and variance for GM.