Trimaran with accomodation in the amas

Hi everybody,
I'm figuring out the best design to combine great space for accomodations,
great comfort with as little motion as possible, and performance.
Accomodations for 16 in 8 cabins, that will be a big thing with the lenght limit of 24 mters / 78'9" for the CE regulation.
For what i read the best design for comfort, stability and performance would be a trimaran, and the catamaran offers more rooms.
In a previous post looking for a trimaran with great living space it was suggested to me the designs of Horstman, and they look very impressive for
the space but even if i read some positive comments about its performance I really can't imagine a big floating thing like the Tristar-60 for example to
perform good sailing close to the wind or hauling.
So now the impossible question:
what would be the minimum lenght of a trimaran to have living space in the amas for queens berth and still good performances?
Yes the "good performances" is a very relative concept; for example - just theoretical - scaling the Chris White design of the hammerhead 54 to 78" keeping the same ratio, would be the amas wide enough to allow accomodations?
Thank you very much,
kind regards
Eiasu

 

Lock Crowther drew "Avatar" which is quite a high performance trimaran available for charter in the Whitsundays. Accomodation for 26 passengers plus 3 crew and two doubles in each float dont think it could configure into seperate cabins though for everyone, more of a berth and curtain arrangement, Trimaraner could give you more information on her. Unfortunately I dont think you could buy plans these days as I imagine they would be part of the permanently "archived" plans.

http://www.ozsail.com.au/our-boats/the-avatar/

 

Kurt Hughes has a 71 foot tri with a massively flared hull (and mezzanine lounges no less) on his website. There is a cross section of the float and main hull with some figures you might be able to scale from. Some of his bigger charter cats might be worth a look too.

http://www.multihulldesigns.com/designs_stock/71tri.html

 

As I understand trimaran design, performance is achieved by minimizing wetted area! Therefore the design usually provides the means to constantly fly at minimum one ama, which in consequence is followed by an undesirable motion in ama located accommodation.
Just figure how it would feel staying in the ama during a tack - from some meters above the waves suddenly to water level, like in an elevator.
If you design the tri for constant contact of all three hulls to the water, you loose the main advantage.
IMHO a cat of similar size would be the better option for high sailing performance in combination with the desired accommodation.

 

Wow this looks realy fantastic!
Eventhough I've read in the comment that the double in the amas are claustophobic. But from outside it looks really slender and beautiful!
Became more and more clear that I will not come to any solution just by pondering numbers and pictures and comments, the only thing is direct sailing experience and feeling the space of the accomodations. There is a tristar60 for sale that has huge space, I cannot imagine it's a good performer, just because displacements and shape but it is worth a try, that would be a great solution!
Thank you for the comments, very usefuls!
cheers
eiasu

 

I think Nigel Irens did one a long time ago, might have been schooner rigged, around 60' (?)........aimed at the charter business.....

 

Probably this one

http://www.sailpromenade.com/introduction.shtml

He did a couple of these while working for a boatyard in Bristol in the 1970's

Gerard Pesty sailed the 55ft Architeuthis in the 1972 OSTAR and finished 6th. I sailed with his son last year. Eric said he learnt to ride his bike in Architeuthis' cockpit!

There is also LammerLaw and its clones.

So there are certainly a number of trimarans with accommodation in the outriggers being used as charter boats.

However you have to go big or it will be a real crouch to get across the bridgedeck. And don't even think of going into the outriggers in any sea. You'll certainly not be able to sleep, even standing will be difficult.

Richard Woods of Woods Designs

www.sailingcatamarans.com

 

was very curios to look at it, but i did not find it !!!

 

The Horstman Tri Stars start using the amas for accomadations at about 38ft, i looked at a foam/glass one in florida in january, pretty impressive space for 38ft.

Steve.

 

And do you know something about her performance? Expecially windward ...

Eiasu

 

I didnt sail it but i sailed on a friends 35ft Tri Star on a short delivery about 35yrs ago and it sailed quite well, we were easily able to catch and pass a 45 ft uldb keelboat on a reach but didnt get to try it out upwind unfortunatly, they do have daggerboards in the amas which should help.

Steve.

 

Promenade was the name I had forgotten, thank you Richard.

There were a bunch of tri's with float accommodations in the 70's, the Symons 49', Hedley Nicol's 45' Voyager, Norman Cross's 46', Piver's 46' Trident, Pi-47, and AA 48, Macouillard's Trimar 52......But none of these could be called a performance multihull...the term "Roomaran" was created to cover the type......

 

Actually the Nicol Voyagers were created to combine decent performance with good room making them successful in the charter industry. One customer I talked to said a couple or small family would be given a ama suite with everyone meeting in the main cabin for meals etc....The slender amas kept the motion from being extreme.

 

While a lot of these older designs may not have performed as well as more performance oriented tris, with modern sails and equipment, some, especially the Cross,Horstman and Nicols would likely sail as well or better than the a lot current cruising cats. The Tristar 38 i looked at was foam cored glass, had huge wing clearance,low frontal area and while it had a mini keel,it had daggerboard trunks in the amas but had never had boards, Decent modern sails, shave the keel and add some modern boards and hardware and it would sail well i believe. Much of the improvements in multis over the years have been in sails,rigs,cordage and hardware more than hull designs.

Steve.

 

Thank you for all your answers, really a lot of useful information,
experience and point of view. Certainly I'm getting more and more interested
of sailing one of the tristar, just to get a direct feeling of performance and space.
Thank you
eiasu