Bilge keel

Bilge keels minimise the draft of the vessel compared to a single fin keel thus enabling it to negotiate shallower water. Bilge keels on sailing yachts extend below the lowest point of the hull extending slightly outwards. Such an arrangement also enables the vessel to stand upright on firm sand or mud at drying moorings without the need for detachable legs, and is simpler than retractable fin keels while giving the hull greater protection. Bilge keels are not as effective as central fin keels in preventing leeway(sideways slippage) caused by crosswinds but are preferred by many small craft owners due to their other advantages.

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