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Old 12-06-2012, 04:38 PM   #33
Tad Roberts
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City: Flattop Islands
Vessel Name: Blackfish
Vessel Model: custom
Join Date: Dec 2012
Posts: 712
Quote:
Originally Posted by bfloyd4445 View Post
I wonder what would happen to get hit on the beam with a large wave in a 8.5 foot wide 40 foot boat?
First of all what's a "large wave"? Is it 3' high or 16' high?

Capsize studies in wave tanks have shown that, if a vessel is laying beam to the sea, a wave with a height (trough to crest) approximately 30% of her length will roll some vessels some of the time. With waves of 60% vessel length, all (of the models tested) will roll every time. So, in theory, a wave of 24' will roll your 40' boat. But much depends on frequency (crest to crest) or steepness of the waves. I've been in huge waves in the open Pacific but the crests were 1/2 a mile apart.....not really steep enough to capsize anything.

I've studied this a fair bit. And the reality is that few recreational boats are lost in North America due to capsize in waves. Most often capsize is due to loads shifting or downflooding......The motor quits and a wave comes over the stern, a combination of downflooding and free surface effect.
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