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Old 05-02-2008, 08:14 AM   #108
parrothead
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Default Wake argument still not jiving

BI I would think that if you lived near a transition from a No Wake to non-No Wake you would prefer performance boats. Because the engine is not what makes a wake, the boat hull does. The horsepower does go somewhere, it goes to moving the boat forward.
The definition of a wake from wikipedia is "a wake is the region of turbulence around a solid body moving relative to the water, caused by the flow of liquid around the body. The wake leading the body is caused by the compression of the liquid medium by the moving body, and is often called a bow wake when observed preceding a watercraft. As with all wave forms, it spreads outward from the source until its energy is overcome or lost, usually by friction or dispersion."

The engine provides thrust not the wake. As the props spin they provide the thrust to move the boat through the water. The shape of the hull determines the type of wake a boat produces.
Descriptions of different hull types from wikipedia.

* Displacement -the hull is supported exclusively or predominantly by the pressure of water displaced by the hull

* Semi-displacement, or semi-planing - the hull form is capable of developing a moderate amount of dynamic lift, however, most of the vessel's weight is still supported through displacement

* Planing - the Planing Hull form is configured to develop positive dynamic pressure so that its draft decreases with increasing speed.

Performance boats are planing hulls. So as they move through the water their wakes decrease. A boat with a planing hull with "enough" horsepower, will be able to transition faster from a big wake to a small wake. As the power increases the positive dynamic pressure increases lifting the hull out of the water. So performance boats are actually good for shoreline erosion.
Now cruisers on the other hand being semi-displacement are worse so lets get rid of them. Or increase their horsepower so they have enough thrust to push those hulls up on plane.

The only reason I can see for not liking performance boats when they transition from no wake up to speed is that they are noisy. So I would accept that performance boats do cause more noise pollution. My neighbor has a Harley with loud pipes, can I banish him too? I don't buy that performance boats are more of a threat to shoreline erosion, and birds nests.
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