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Default Fiberglass vs plastic

The H20 after the Nordkapps name means "Hatches Two Oval" meaning that both
the front and rear hatches are oval instead of the configuration of the
Nordkapp Jubalee, which had only one (the rear one) hatch oval. Pre 1992 or
93 Nordkapps had only the 7 1/2 inch round hatches

Depending on the year , the Nordkapp ranges from 17 foot 8 inches to about
18 feet




"William R. Watt" wrote in message
...


I found what I was looking for at www.greenval.com/winters.html.
Writing about canoe design for frictional resistance John Winter says ...

"A 5% decrese in wetted surface is worth bragging about, but a
single year's scratches and banging can easily double coefficient
of friction from 0.004 on a new fibreglass canoe to 0.008. This
more than offsets the designer's efforts. The cavalier attitude of
most canoeists towards their boats is evidence that a 50%
resistance increase is not often noticed if only because the onset
of its effect is so gradual."

Earlier I wrote in this online discussion that paddling in a group
would require extra effort to keep up with other members who were
in similar boats with smooth hulls. I only assumed a 10% increase
in frictional resistance. Winters implies a 50% increase is not
unusual. I used performance data from Winters' former website. All
Winters data applies to canoes (at one point he mentions a
"typical" 16 foot canoe) and is provided to illustrate the
principles he is writing about. Its not specific to any boat,
particularly not kayaks.

I was kicked off the computer at the public library after an hour,
but not before taking a look at the kayak data provided by Mike
Daly at http://www.greatlakeskayaker.ca/spee...anceGraphs.htm. I
found the graph very interesting. I've copied down the numbers and
would like to replace the resistance in pounds by the effort in
horsepower when I get a free moment. Of the 5 kayaks, the
Endurance 18 and the Arctic Hawk are equivalent and fastest. I
don't know if they are the same length. However the Nordkapp H20
and the Solstice GT are equivalent and second fastest even though
the Nordkapp is 2 ft longer than the Endurance (if I'm
interpreting the names correctly). Up to a speed of 4 knots all
four of these kayaks are equivalent. The two pairs only begin to
diverge at speeds over 4 knots. The remaining kayak, Sonoma, is
the slowest. Its length is unknown. There is an error in the data
for the Sonoma at the fastest speed, revealed by a sudden change
in its graph. The slowest boat is one for which John Winters
suppled the data and I'm sure it is for a canoe, not a kayak, as
all the Winters data I've seen is for canoes.

Even though the boats I currently paddle are only cheap home made
experimental plywood boats I'm careful not to treat them roughly
and get the hulls scratched and gouged. That is why I was so
disgusted to see the condition of the used rental boats offered at
a recent sale here.

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