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Re: S&G: Fast sea kayak
By:skiffrace
Date: 11/29/2007, 9:49 am
In Response To: Re: S&G: Fast sea kayak (Bill Hamm)

: One thing you'll find is you're going to give up some stability (at least
: primary stability) to gain speed. No such thing as a fast sea kayak that's
: 23" wide. The fast ones are skinny, you just have to learn to like it
- : :)

: Bill H.

Bill,

I have downloaded the Free!Ship program. It has the predicted drag calculator using the KAPER formula.

I have plugged-in numbers for several different kayaks, and also played a little with the input parameters.

What I am going to say next assumes the KAPER calculates the drag correctly and considers all the important factors.

Anyway, I found that these boat parameters have significant influence on the predicted drag at the **high end of the speed spectrum** (as opposed to the low end which did not interest me for obvious reasons)

-Length waterline
-Wetted surface area
-Prismatic coefficient

-Longitudinal Center of buoyancy does have some effect-as the swede form increases the speed improves.

These parameters appear to have much smaller effect:
-Beam waterline (a surprise, isn't it)
-Draft

Again, this is a very "eyeball-measurement" opinion, try it on your own and see what you read out of this.

-Tom

Messages In This Thread

S&G: Fast sea kayak
skiffrace -- 11/28/2007, 2:47 pm
Re: S&G: Fast sea kayak
Scott Baxter -- 11/30/2007, 12:47 am
Re: S&G: Fast sea kayak
Bill Hamm -- 11/29/2007, 2:24 am
Re: S&G: Fast sea kayak
skiffrace -- 11/29/2007, 9:49 am
Re: S&G: Fast sea kayak
Bryan Hansel -- 11/29/2007, 6:34 pm
Re: S&G: Fast sea kayak
Paul Sylvester -- 12/3/2007, 7:17 am
Re: S&G: Fast sea kayak
Bill Hamm -- 11/29/2007, 1:50 pm
Re: S&G: Fast sea kayak------WebKitFormBoundarycnH *LINK*
Bob Deutsch------WebKitFormBoundarycnHGkr+OjYnXUws -- 11/28/2007, 3:52 pm
Re: S&G: Fast sea kayak------WebKitFormBoundaryMj+
Bob Deutsch------WebKitFormBoundaryMj+41hHLCDocqqN -- 11/28/2007, 3:57 pm
Re: S&G: Fast sea kayak------WebKitFormBoundaryMj+
Nick Schade - Guillemot Kayaks -- 11/28/2007, 4:08 pm
Re: S&G: Fast sea kayak------WebKitFormBoundaryMj+
Bob Deutsch------WebKitFormBoundaryMj+41hHLCDocqqN -- 11/28/2007, 5:19 pm
Firefox doesn't create the garbage *LINK*
Nick Schade - Guillemot Kayaks -- 12/3/2007, 9:00 am