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Old 02-05-2019, 06:23 PM   #65
Nomad Willy
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City: Concrete Washington State
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 18,743
Fish writes the SD hull is the bastard child in hull design. Indeed it is. Kind of a “morfidite” but important as it fills the gap between planing and FD. A planing hull does SD speeds but very inefficiently and w/o enough speed to be in solid control with her small rudders and even smaller keel. The SD hull offers some speed w significantly better economy than the planing hull. Without the SD boat rec trawlers would be stuck with 6-8 knots or a planing hull. Rec Trawlers probably owe their existance to the SD hull. Note that SD boats designed for the upper range of SD speed are very close to planing hulls and frequently called the wrong hull type. Often on TF (not so much as in the past) people would call SD boats FD. If we tried to label some boats half of us would say it’s FD and the other half would say SD. And since there’s no clear decisive description of both types the boat is just in a grey zone. Probably 20% (or more) of the trawlers here are in this grey zone. All one can do is hear and evaluate some differing opinions on the same hull. And then draw you’re own conclusion.
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Eric

North Western Washington State USA
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