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This site was last updated on the 18/5/18
These boats are probably the easiest to relate to for the public. Displacements are, from a distance, the closest resemblance to your average water ski boat. With the engine mounted "inboard", usually at the rear of the boat.
Obviously these finely tuned racing boats are a little different than your average ski boat. Construction materials range from fibreglass & plywood through to the high-tech materials of kevlar & carbon fibre, making these craft very light and very strong in relation to your average ski boat.
The term "displacement" is derived from the the action of the boat "displacing" (pushing the water out of the way) the water as it moves through the water.
Displacement classes range from 3.4 litre skiffs all the way up to the monstrous Blown Alcohol Displacements.
Classes are based on engine capacity. There are generally no restrictions on engine configuration (straight 6, V8, etc) or make or model. There are exceptions in a couple of classes, which are generally aimed at controlled, even racing.
These classes are the most active displacement classes in Australia at this time: