Squat is an important issue for ships navigating with limited under keel clearance in restricted waterways such aschannels and canals. The admittance policy for containerships on the Western Scheldt, a tidal estuary in theNetherlands giving access to the port of Antwerp (Belgium), is based on a minimal static under keel clearance toensure safe passages on the river. A large number of captive model tests executed in the Towing Tank forManoeuvres in Shallow Water (co-operation Flanders Hydraulics Research - Ghent University) have beenevaluated to determine squat prediction formulae. Measured sinkage and trim depend on a number of parameterslike ship velocity components, ship loading condition, propeller action, blockage of the waterway, bankgeometries and characteristics of other shipping traffic. The derived mathematical models have beenimplemented in the ship manoeuvring simulators of FHR to visualize the dynamic under keel clearance duringreal-time simulations at different locations on the Western Scheldt
