[Paddlewise] Rudders redux

> John asked about extra drag from having the kayak leaned to turn it or
> correct a course. (SNIP)

I certainly don't have any data and that is why I would never make any 
claims about it. Tank researchers would tow the boats heeled as well as 
upright like they do sailboats and that would give some insight. They would 
also tow the boats at different leeway angles ot see if the boats made more 
or less leeway and under what circumstances. Matt could run the numbers 
through the Taylor Standard series and that might be interesting. Sea 
Kayaker could run them with KAPER although I would have little faith in the 
results if the heeled shapes fell outside the database used to create KAPER. 
(would it not be interesting if it were discovered that some boats have less 
resistance when heeled than when upright) Those people that wrote the book 
that Craig says has no application could do oxygen take-up tests while a 
person rolls a boat and then compare it to the effort required to steer the 
boat with a rudder. Sports biomechanics folks could could study muscle usage 
etc. to determine if one method is harder on the body than the other. 
Pooling all this data would probably lead to a lot of insight and lead us 
away from speculation and opinion.

Matt also wrote;

> Oh, I guess that is just poor design again so we shouldn't consider it a
> problem with rudders in general. (SNIP)

Matt, that is beneath you.

Craig wrote;


> Caffyn recorded a nearly-33% increase in daily mileage with a rudder
> compared to no rudder.

This is really interesting. Matt reports that the rudder adds 10% additional 
drag.

Who is right? Matt and Craig, how do you explain this? Are both of you 
right?

I wonder what kind of statement Caffyn would make if he had paddled a 
Mariner XL around Australia. :-)

Cheers

John Winters
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