Re: [Paddlewise] Planing

At 9:36 AM -0500 1/17/02, John Winters wrote:
>
>Nick wrote:
>
>>  Maybe not all kayaks
>>actually start planing in surf, but those that do so more readily are
>>faster and generally considered "better" surfing boats.  This ability
>>can be designed into the kayak. "Surfing" and "planing" are not be
>>the same thing, but they can happen at the same time.
>
>These things always cause problems.  However, Dr. Savitsky pointed out that
>the rise in CG during surfing could occur but you could not call it planing
>any more than you could say a person falling off a building was flying
>because he generated some lift. The distinction between planing and not
>planing is the vertical rise caused by the boat's power not an outside
>source.

OK, I guess there is a definition out there that precludes using the 
word "planing" when the boat is "surfing". Can you use "planing" to 
describe what is happening with a water ski? How about if you put a 
model of a planing boat in a tow tank? Is the data collected 
meaningless because the power comes from an outside source? How about 
one pontoon of a catamaran where it is the other pontoon that has the 
motor. The source of the power strikes me as a funny way of 
discriminating how a hull moves through the water.

Again, I want to note that I am not saying all surfing involves 
planing, just that many kayaks do something that looks an awful lot 
like planing while surfing. There are times surfing on small waves 
when the wave just pushes the boat along through the water and 
nothing seems much different from regular paddling accept it is 
easier (displacement mode?).

Then there are times on bigger waves when all of a sudden the boat 
breaks free and starts flying down the wave, the boat bouncing along 
the surface instead of pushing through the water. The difference is 
not just that it is getting a boost in power. The boat noticeably 
lifts and performs completely differently. This happens at a 
distinctly noticeable and sudden transition. Am I not permitted to 
call this "planing" because some portion of the power required to 
reach that point comes from the wave? If not, not how does one 
distinguish between the slower push-through-the-water mode, and the 
faster up-on-the-surface mode? What are the proper words?

>
>Sorry to see you go Jackie. The professor is despondent. He has taken to his
>cage and refuses to come out or eat. I have see him  in this kind of funk
>before and it is frightening. I just hope he can dig himself out.

Give him a couple ballast rocks to throw around for awhile. It might 
help him work out his anxiety.
-- 
Nick Schade
Guillemot Kayaks
824 Thompson St
Glastonbury, CT 06033
(860) 659-8847
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