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Re: kayak "freeboard"
By:Paul G. Jacobson
Date: 10/5/2000, 1:03 am
In Response To: kayak "freeboard" (Jim Eisenmenger)

: I've been able to test paddle my almost completed Guillemot S&G a couple of
: times and am curious about the gear I will be able to carry since I
: decreased the volume of the design and built it heavier than what was
: probably justified. I'm an experienced canoe tripper, and we canoeists
: have the concept of freeboard that should be maintained (<6" at
: the center of a canoe indicates overloading). Is there a similar rule of
: thumb in kayaking?

With an open boat you want to keep the sides of the boat high enough to keep out splashes and waves. when the first person put a deck on their canoe, and turned it into a kayak they discovered that they no longer had to fear small waves. When they added a sprayskirt they found that they no longer had to fear ANY waves. By sealing the top of their boat they eliminated the inflow of water which would weigh down the boat, and eventually capsize it. With no water getting inside, the displacement remains the same, the bouyancy remains the same, and the paddler can even be totally submerged for a while -- so "freeboard" becomes a non-issue.

If you are not totally sealed into your kayak, then what you should look at is how high the opening of the cockpit is above the water line. Working with the canoeists number of 6 inches, and going to an extreme situation, assume the cockpit coaming was shaped like a chimney, and a foot tall. You could have your kayak's hull and deck totally submerged, with maybe 6 inches of water over the deck, and still not get any water inside, because the opening would still be 6 inches above the water.

Now think about the peaked decks on some kayaks. these effectively raise the cockpit opening higher above the water line than non peaked decks.

On the other hand, cockpits with low backs, which some people seem to like for ease of rolling, give you an opening which is lower. this would let in water more easily.

If you wear a sprayskirt which seals real well then you could load down a kayak much more than you could do with a canoe, and sink it deeper into the water than you would reasonably put a canoe, and still not ship water.

Hope this helps.

Paul G. Jacobson

Messages In This Thread

kayak "freeboard"
Jim Eisenmenger -- 10/4/2000, 9:17 am
Re: kayak "freeboard"
Paul G. Jacobson -- 10/5/2000, 1:03 am
Chimney Coaming *Pic*
Spidey -- 10/5/2000, 10:41 pm
Re: Chimney Coaming
Matt Thyer -- 10/10/2000, 4:20 pm
Re: kayak "freeboard"
Mike Scarborough -- 10/5/2000, 8:59 pm