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Michael Daly
 
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Default Paddler's Weight vs. Stability and Performance?

On 21-Jun-2004, Wright wrote:

I have seen the reviews in Sea Kayaker magazine and they assume, if
I am understanding them correctly, that the center of gravity for both the
lighter and the heavier paddler is 10 inches from the low point of the seat.
In other words the center of gravity is at exactly the same place for both
paddlers (without any gear). Yet the curve for the lighter paddler
indicates more stability.


Interesting - I never noticed that comment about CG position in the reviews.
Since these are static and not dynamic stability calculations, the mass at
the CG is all that matters. If both the heavy and light paddlers have their
mass at the same point, then the only difference is the quantity and the
stability curves do not reflect the difference in distribution.

Since that CG (10" up and 10" forward) is above the center of bouyancy, any
heeling will have it contribute to the overturning moment. The heavier
paddler will still have the lesser stability at a given angle of heel. If
the CG was determined for real paddlers, taking into account different CG
positions, the moments calculated would be slightly different.

Don't forget that these figures still ignore the fact that a real paddler
will tend to keep his/her body roughly vertical if the kayak heels. This
greatly changes the overturning moments.

Mike