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Topic Review (Newest First)
01-27-2012 07:24 PM
Originally Posted by mikieg
ok, so what is a good number?
A capsize ratio of around 2 is considered to be getting into the slow-to-recover range. Nigel Calder's "Cruising Handbook," has a good section on relative strengths and weaknesses of hull design and explains this ratio pretty well. US Sailing and a number of other sites have info. on this ratio.
01-27-2012 07:19 PM
I leave the cockpit as soon as the drogue is out, and there is nothing more I can do.
01-27-2012 07:18 PM
Originally Posted by jackdale
The Fatal Storm and Proving Ground (The 1998 Sydney Hobart Race) should be right next to Fastnet Force 10 on you bookshelf. There are a couple of examples of capsized boats with tethered crews.
When cruising wear a PLB. It "might" help.
Here are some could clips from 98 Hobart- make sure you see a 5 parts.
tell me about this capsize ratio. how is it calculated and what is a good number?
01-27-2012 08:32 AM
Capsize ratio was #1 on my list of design factors in choosing an Alberg 35 to renovate and sail. It came in WAY ahead of speed, cabin space, and resale value. In the event of an actual 360 degree roll, differentiated from a knockdown, from what I've read, the mast/rigging will almost surely break. The swages/aluminum/s.s. is nowhere near strong enough to absorb the force of water, leveraged against the boat by the length of the rig. Even if you're below, this will require getting on deck to secure the battering ram that is likely still attached by the rigging that did not break. If far from help, saving pieces could be used to jury rig. So, you're going to be tethered to a boat being tossed around by breaking waves, rigging flying about, boat in danger of rolling again with you on deck. Would some sort of small rebreather be a wise thing to have if you ever have to be on deck in these conditions? As long as the hatches and boards are in you KNOW she will right herself eventually. Is it wise to even use an inflatable pfd which may go off at the wrong moment as you're struggling to secure the rig? Do you want one to go off if you're clinging like a barnacle to the inverted boat?
01-27-2012 03:09 AM
this is a damned good thread. these are indeed the very things i think about! i am looking forward to reading all the replies.
01-27-2012 02:14 AM
The book Desirable and Undesirable Characteristics of Offshore Yachts
has a chapter which describes tests of yachts in wave pools. They capsize boats and measure their ability to right themselves. Of course, if your main is up and sheeted in tight, or if when your boat is capsized it becomes a flat bottom boat, the time to right itself is significantly longer.
Knowing the characteristics of the boat you're sailing should inform your decision of when to go below and how to 'gracefully degrade' from the effort to make way.
Additional good advice in this book includes - having a mast with a Storm Tri-sail bent on and ready to go... for instance, the Lefiell OM3D mast has a 2nd integral track for a storm tri-sail. Cruising Mast & Boom Assemblies.
This book was an easy read... I absorbed it in 3 weeks... Lots of expert knowledge regarding cruising boats.
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