ABSTRACT
Measurements performed on vessels are aimed at determining the up-to-date technical condition of the elements of the main propulsion or the evaluation of the operating elements of a vessel. The diagnostic measurements should be performed in a continuous manner, and the measurements to determine propulsion characteristics should be performed at specified time points, e.g. after completing the construction works on the vessel, after repairing elements of the propulsion system, etc. The measurements are performed on a vessel to develop propulsion forecast for a new built ship, or to evaluate current operating parameters of an exploited vessel. Irrespective of the aim of the measurements, it should be noted that a vessel always works in different conditions and the conditions may affect the quality and reliability of measurements. The change of the conditions for vessel movement is induced by parameters linked with: the vessel, i.e. vessel loading, use of reserves
(change in displacement), change in the condition of hull, propellers, engines, etc.
