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Old 05-10-2006, 07:25   #31
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ill just say this if you have a mono and a cat that both have an equally large size hole in the hull i know which boat anyone on this forum would rather be on, ta da the catamaran, its like playing 5 hundred with three extra jokers, bouyancy, extra accomodation even if it is upside down, shallow draft, and you can still carry the same safety equipment as a mono maran
sean
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Old 05-10-2006, 18:31   #32
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Quote:
Originally Posted by Joli
Yea, but selling the fact as safety is still a false sense of secuity if you are not found.

http://www.sailinganarchy.com/forums...994&hl=capsize
Actually the boat WAS found. Unfortunately nobody was with it. However, if it had been floating in such a way as to be livable, ( like most multihulls would) and the crew had stayed with it, they would have been found.
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Old 06-10-2006, 08:58   #33
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Quote:
Originally Posted by schoonerdog
using John Shuttleworths static wind capsize formula our boat would start to lift her hull in 24.2 knots of wind beam to.
Sorry to call your math into question, but that doesn't sound right at all. An F41 (lighter, with bigger sails than a St Francis 44) has a static capsize windspeed of 36 knots. An F25C (very fast race boat) has a static capsize windspeed of 28 knots. Real lunatic fringe race boats are somewhere down in the low twenties.

Since wind speed is reported as seventieth prercentile and gust as ninetieth, sailing a boat at 80% of its static capsize windspeed is playing with fire. Guaranteed to piss the admiral off. While it is true that the force exerted on the boat is much less than the 80% would imply (because force exerted by the wind rises as the square of the velocity) the concern is the probability that the force exerted will exceed 100% and the fate of the martinis immediately thereafter.

FWIW, I usually reef Endless Summer (my F41) at half the static capsize windspeed and have never regretted it. As the wind comes over 15 knots we start to get overpressed and just pump energy back into the ocean. Reefing is much easier on the boat and crew and barely slows us down.

-Scott
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Old 06-10-2006, 10:09   #34
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John Bickford said: "The lower half of the forward compartments on our 43 footer are filled with foam to protect watertight integrity in case of striking something hard (e.g. reef, coral head, awash container box)."

I think you'll find that the space under the rear stairs of your Fountaine Pajot are foam-filled as well, giving 4 blocks of solid, protected foam, well distributed against the bottom of the hull!!!
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Old 06-10-2006, 10:48   #35
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Fountaine Pajot and Foam

I almost forgot. The Fountaine Pajot keels are foam-filled contained units that fit into female slots inside the hulls, making two more foam blocks. And if they are hit or compromised, they do not affect the hull itself.

I consider an FP boat, an EPIRB, a liferaft, painting the keels red, and a 5-day forecast as the foundation of a good safety program. This provides the redundancy that a monohull cannot.

To be honest, those escape hatches always have a tiny annoying leak, and that bugs me.
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Old 06-10-2006, 11:09   #36
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Quote:
Originally Posted by Sonosailor
those escape hatches always have a tiny annoying leak, and that bugs me.
There have been several cases of cats being sunk due to those "escape hatches" - people crack them open for air in harbour, and they are so close to the waterline, especially if the stern squats under power, that they can become submerged. They are normally standard boat hatches and are certainly not designed for this purpose. I personally would not have them.
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Old 06-10-2006, 13:10   #37
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SMM,

I believe the key word might be "starting" to lift. I didn't do the math myself, but had a friend whose a naval architect look at the numbers. He looked at the sailplan center of effort and the distance between the centers of the hulls, not the overall beam. His numbers do make sense though for lightship displacement, our boat fully loaded would have higher static stability with the numbers increasing towards 26 knots. St Francis 44 is a typical light cruiser racer catamaran.

From the following link http://www.john-shuttleworth.com/Articles/NESTalk.html

Per John Shuttleworth:
"Typical values for SF can vary between 12 mph for a Formula 40 racing catamaran, to over 40 mph for cruising multihulls. Modern light cruiser racers would be in the range of 24 to 30 mph. So it is clear that in addition to the different types of multihull listed above the initial static stability can vary enormously."
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Old 06-10-2006, 14:07   #38
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I have held full main and genoa on my 9m Catalac with the wind an apparent 32 kts from 45 degrees. I was manually handling the main to cope with additional higher gusts. Boat was doing 10 kts and I was enjoying the sail.
I normally reef initially at abt 22 kts.
Boat speed will increase by at least 1 kt when wind increases from 15 kts to 18 kts apparent.
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