Re: [Paddlewise] Rollability Hypothosis

Hi Nick,

I have found my CLC Chesapeake 17 to be a bear to roll.  It is fairly
wide-beamed (24.5" at sheer, about 23.5" at waterline) and the hard
chines seem to drag a lot of water when you're rolling up.  It is VERY
difficult to get near 90* (either from 0* to 90* or from 180* to 90*). 
I would say that its stability curve is great from 0* to 50* and from
140* to 180* but it doesn't want to stay near 90* for long.  Of course,
these numbers are all subjective, and I've never seen the actual curves
for this boat, but I would quantify it as a not-so-easy-to-roll boat.

Of course, Greenland kayaks have hard chines, so my hard-chined opinion
is probably worthless.

As for getting most of the way up--are you postulating that people get
their bodies most of the way up (but not the boats) and fail as a
result; or that people get the boat most of the way up, but fail on the
way to getting their bodies and heads into an oxygen-rich environment? 
A very low aft deck and aft coaming also contribute to rollability, as
it allows for a much lower center of gravity, and a smaller righting arm
in the kayak/kayaker system.

There are boats out there with narrower beams and rounder hull sections
that feel a lot easier to roll--the CD Extreme, Prijon Topolino and Topo
Duo, and your Guillemot come to mind.  

Yeah, I'll buy that a relatively flat stability curve from one angle to
the next would make for a more easily-rolled boat.  I would also think
that a lower curve on a stability graph would make a more easily rolled
boat than a curve of the same slope with higher points.

-- 
Shawn W. Baker          0                                    46°53'N
© 2000            ____©/______                              114°06'W
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baker_at_montana.com    0        http://www.geocities.com/shawnkayak/
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