Emergency Flotation

[jimboaw]

By choice we have no liferaft so in the event of a major disaster we will have to depend on our always inflated dink. We do have a 406 EPIRB and all our sailing is done in relatively well travelled waters US. E. coast, Carribean and Gulf of Mexico.We have been thinking about sailing home (GB) this summer and the liferaft issue has been raised by SWMBO.
What I need to know is just how many cubic ft of flotation will keep my 40ft floating home from completly going under?. The hull itself, less engine and ballast is probably about neutral boyancy as it has 5 foam filled stringers each side as well as laterals every 30 inches. Add to that water and fuel tanks plus other none sinkable stuff.
Am I crazy or could flotation bags inside the hull rigged to a couple of old dive tanks keep us afloat long enough for a rescue??

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[Talbot]

Your biggest problem is the buoyancy needed to counteract your keel. The sums required are relatively straightforward, and it would be feasible to inflate something inside your boat for a short period, but the biggest problems would be securing it to the deck and preventing chafe. not only that but where would you then stay? cause the habitation would be full of inflated bag /forums/images/icons/smile.gif Furthermore your boat would then be practically submerged, so would not be able to progress further, and would not be a very visible target for the rescue services. IMHO the concept is a no-no for ocean passages unless fitted from build (and I am not really convinced of that either) so buy a good liferaft - and make sure that it has a double floor and a survival pack, to which you will need to add at least a solar still and space blankets. The only real alternative to this is to have a tinker star traveller outfitted as a liferaft and including a sailing pack. I would also suggest that during your long passage you deflate and stow your tender cause it will become a real liability in a storm. Good Luck - I will be travelling the other way in a few years.

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[BrendanS]

It's been discussed a few times before <A target="_blank" HREF=http://www.ybw.com/cgi-bin/forums/showflat.pl?Cat=&Board=ym&Number=320597&page=&view=&sb=&o=&vc=1>click here for one example</A>

<hr width=100% size=1>There is no such thing as "fun for the whole family."

 

[William_H]

Without any real experience of ocean voyages or of larger yachts mine being 21 foot, let me make some comment. Life rafts are pretty terrible things if you have to use it in a storm. liable to capsize and not at all comfortable.
The idea of blow up flotation doesn't seem like a good idea. My theory is that you shoulod stop the boat filling and sinking in the first place. Consider filling the bilges with foam as I did. ( no engine) consider sealing under bunk spaces or lockers so that they are used for gear not normally required or kept empty. Consider water tight bulkheads to seal aft and bow areas. It should not be that hard compared to the cost of a life raft to partition and seal enough boat to stop it sinking regards will

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[joeh]

dave gerr in his book nature of boats provide a method of calculation

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