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Re: Skin-on-Frame: Sea Sled catamaran prototype
By:Carl Delo
Date: 7/2/2008, 10:05 am
In Response To: Re: Skin-on-Frame: Sea Sled catamaran prototype (Etienne Muller)

: I wonder if these asymetrical hulls are not going to create drag through
: lift. I would think that the flow passing along the flat side is going to
: pass more easilly than the flow along the curved side, creating the effect
: of the hulls wanting to separate. Not being able to do this there could be
: vortices formed which will interrupt the flow.

: If I were to build such a boat I would consider two thin but symetrical
: hulls, perhaps with not too much of a knife edged keel, as this, while
: giving direction, may also cause drag.

Et - My hulls are 16'6" long by about 7" max beam, max draft around 9", bow angle 3 degrees. The interior clear space between hulls will be 16" +/- to allow a person to fit between - this is one of the design constraints for my boat. As Bill said, the inner walls of the hulls will have some camber, but not much. There will probably be lateral lifting forces, but at the low speeds in paddling, I think it won't add up to much (I hope). After all, when a normal kayak is edged the hull becomes asymmetrical, so should develop lateral lift also - but no one complains about lateral slip due to lift while edging.

You may be right about the knife edge keel - I worry it won't turn at all, and will need huge rudders. Hopefully, the structure of the prototype should allow retrofitting a more rounded keel and increased rocker if needed. Ok, back to it - Carl

Messages In This Thread

Skin-on-Frame: Sea Sled catamaran prototype *LINK*
Carl Delo -- 7/1/2008, 11:36 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/3/2008, 1:30 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *Pic*
Carl Delo -- 7/3/2008, 8:47 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/3/2008, 9:38 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *LINK*
Carl Delo -- 7/3/2008, 8:34 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/3/2008, 9:43 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/2/2008, 1:31 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Etienne Muller -- 7/2/2008, 6:35 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/3/2008, 1:58 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Etienne Muller -- 7/3/2008, 9:19 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 7/3/2008, 8:10 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/10/2008, 3:10 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *LINK*
Carl Delo -- 7/10/2008, 9:04 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/11/2008, 10:04 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *Pic*
Carl Delo -- 7/11/2008, 10:53 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/11/2008, 11:28 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/21/2008, 1:38 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *LINK* *Pic*
Carl Delo -- 7/22/2008, 10:39 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/23/2008, 9:53 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 7/23/2008, 10:20 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/24/2008, 3:04 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 7/24/2008, 11:41 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/25/2008, 12:21 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/26/2008, 2:07 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *LINK*
Carl Delo -- 7/27/2008, 11:45 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/29/2008, 4:26 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype *Pic*
Carl Delo -- 7/29/2008, 4:48 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/31/2008, 9:00 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 7/31/2008, 9:36 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/31/2008, 6:55 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 8/4/2008, 12:53 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 8/6/2008, 3:52 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/31/2008, 12:39 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype *Pic*
Carl Delo -- 8/1/2008, 12:40 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *LINK*
Pablo -- 9/26/2008, 3:14 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype *LINK*
Pablo -- 9/26/2008, 3:18 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 9/27/2008, 11:17 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 8/1/2008, 9:45 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/30/2008, 1:45 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/28/2008, 2:37 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/24/2008, 10:54 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/23/2008, 3:24 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/23/2008, 8:49 am
Re: Skin-on-Frame: Sea Sled catamaran prototype *NM*
Bill Hamm -- 7/23/2008, 8:45 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/10/2008, 4:47 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/5/2008, 1:52 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 7/5/2008, 6:54 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/5/2008, 7:43 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype *Pic*
Carl Delo -- 7/5/2008, 11:38 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/7/2008, 6:55 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/8/2008, 5:57 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/6/2008, 2:10 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/5/2008, 7:39 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Etienne Muller -- 7/4/2008, 4:53 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Carl Delo -- 7/2/2008, 10:05 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/2/2008, 12:22 pm
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/2/2008, 9:34 am
Re: Skin-on-Frame: Sea Sled catamaran prototype
Bill Hamm -- 7/2/2008, 9:20 am