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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. -- -------------------------------------------------------------------------- ---- William R Watt National Capital FreeNet Ottawa's free community network homepage: www.ncf.ca/~ag384/top.htm warning: non-freenet email must have "notspam" in subject or it's returned |
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