Whats the difference between Planing and Displacement Hulls?
Displacement hulls will “displace” (push away) water equal to the boat’s total weight. As the sailboat moves through the water, this is evidenced by the waves the boat creates. Round bottom hull of a Tradewinds 26 is a good example of a displacement hull, as it cuts through the water with a minimum of propulsion (via sail or motor). Small engines can drive the boat, and so, can go longer distances with less fuel; and because the boat is going through the water, there is a smoother ride. Planing hulls actually act like displacement hulls – until the boat has achieved “planing speed” – when the boat lifts itself on top of its own bow wave. The boat displaces much less water, allowing an increase in speed. Sailboats with semi-planing hulls, as the Leeward 16, have some lift capability after a certain amount of forward momentum has been achieved.