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Re: S&G: Fast sea kayak
By:Bill Hamm
Date: 11/29/2007, 1:50 pm
In Response To: Re: S&G: Fast sea kayak (skiffrace)

: - : :)

: 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

Hi Tom,

Ok, was going to launch into a huge long letter on boat design, but dawned on me that our host Nick has an excellent page on that here on his web site. Recommend reading that one. Also I've not had my first cup of coffee yet and am not thinking too quickly :) also this is my first day off in 12 days .

If you look around at the fast sea kayaks you'll find that skinnier "is" faster, I've paddled quite a few since I like fast (relative term ) too. For a stitch and glue you might look at CLC's Pax 18 or 20, depending on your weight, both are quite narrow. With my very limited experience with Tom Yost's designs (water got cold quick this season) his long boats are quite fast too, and are really skinny.

Read Nick's stuff first :)

Bill H.

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