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  #46  
Old 05-15-2006, 08:55 PM
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Vega Vega is offline
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Quote:
Originally Posted by Raggi_Thor
I think there are differences between coastal cruising and offshore, ocean crossings. How is he movement of a lightweight catamaran?
There are no heavy weight cats. And the movement is what should be expected of a light craft that takes with the same wave twice, first one hull, then on the other, jerky motion is what you get. Not a comfortable boat in troubled waters.
Good for calm waters and for enjoying life when moored and a headache at the time of trying to find a place in a marina and when paying the bill…. prices and places

Quote:
Originally Posted by FAST FRED


Most of the cats I have been on stank as ocean crossers as the performance NEVER exceded the expected hull speed of a lead sled. A 65 ft cat cruising at 8k is hardly worth the risk,cost or dock finding hassles and expense.

FAST FRED
There is a good article about cats at sailnet, by John Kretschmer, a deliver skipper, , that has delivered all kinds of boats, including cats. What he says about the subject is interesting:

“this Fountaine-Pajot Venezia 42 maintained poise as she tracked over the Atlantic, easily coping with the six to eight-foot seas rushing between her hulls.

The Venezia's speed was a consistent seven to eight knots with an occasional low, double-digit spurt when surfing down a wave. My 20-year-old, 44-foot steel ketch could keep pace in these conditions, ....

And cats do sail flat. The lack of rolling downwind is refreshing, especially on a long trade-wind passage. Most of today's cruising cats are well-designed, engineered, and constructed.

But I have discovered compromises. It takes awhile to adjust to the lack of heel, a result of high initial stability, and the ensuing fast, jerky motion. These cats in general have a lot more motion than a monohull. Also, as designers create more interior volume in the saloon, they lose wing clearance, or bridgedeck freeboard, between the hulls. This can result in a great deal of pounding and slamming underneath, especially when sailing upwind in big seas.

During a Force-9 gale in the Venezia two years ago, the water action between the hulls was at times so violent it created a 10-foot-high geyser through the bridgedeck scuppers. Beating across the Yucatan Straits in the St. Francis was slow going and in the aft cabins you felt like you were inside a kettledrum. Indeed, as cats tend to slap at every passing wave, the noise requires some acclimation.

…. Cruising cats, as well as many of today's performance monohulls, simply cannot be overloaded. This will not only cause them to lose speed but also to become sluggish and difficult to handle. (One distinct advantage of a heavy-displacement cruising boat is that you can pile on gear and provisions without significantly altering performance.)

The earlier mentioned gale developed out of the southeast shortly after we cleared Cape Hatteras. …
Although the hulls rarely pounded in the rising seas, the water action between the hulls was significant. I didn't question the structural integrity of the boat, but I was surprised at the amount of slamming and slapping that the after-hull sections took. We had a scare when the latch supports of the emergency hatches in both heads broke. Suddenly we had open hatches four inches above the water with no way to secure them. We sacrificed handles from a mop and boathook and lashed them across each hatch. The hatches still leaked but at least the sea was kept out….

Ironically, my initial anxiety about being caught out in a cat gave way to frustration. We were unable to make much progress during the blow. I decided to accept Neptune's fate and shortened sail further, reducing our forward speed to around three knots. .


http://www.sailnet.com/collections/a...leid=jkrets006
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  #47  
Old 05-16-2006, 05:35 AM
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Raggi_Thor Raggi_Thor is offline
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Quote:
Originally Posted by Vega
There are no heavy weight cats. And the movement is what should be expected of a light craft that takes with the same wave twice, first one hull, then on the other, jerky motion is what you get. Not a comfortable boat in troubled waters.
Good for calm waters and for enjoying life when moored and a headache at the time of trying to find a place in a marina and when paying the bill….
Thats what I thought :-)I don't understand why people want to cross oceans on a jerky platform...
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