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Old 11-03-2009
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Quote:
Originally Posted by Paul_L View Post
Look what goes into the capsize screening formula, i.e. Capsize Ratio:
Capsize Screening Formula = Beam / (Displacement / 64)1/3
Displacement is in Pounds
Beam is measured in Feet


It really doesn't tell you much of anything about stability. Like the weight can be anywhere and not effect stability -- I don't think so.


Paul L
The denominator in that equation is the cube root of the volume. (64 is the specific gravity of seawater, so that is just giving you the immersed volume), so it's really just a simple ratio of beam to volume.

It's one of those things you use early in a design to see if you're in the ballpark, but Paul and Jeff are right that it doesn't really tell you heaps about the real performance of the hull.

There's a reasonable chance that PacSea has the righting arm numbers and be willing to share, or at least tell you what the heeling angle at least positive stability is. I know there are also some really excellent PacSea brokers out there who are encyclopedic with this stuff.
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Ryan Roberts
S/V ARGO - Pacific Seacraft 37 Hull No. 309
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