"Michael Daly" ) writes:
On 28-May-2004, (William R. Watt) wrote:

at sustained (cruising) paddling speeds hull resistance is still the
biggest component of total hull drag when comparing identical boats. there
are some numbers in a file on my website under "Boats" on average hull,
wind, and wave resistance, and energy consumption. a paddler can't put out
the power needed to maintain high wave making resistance speeds for any
length of time.

Nowhere on your website could I find info to support this.

look under Boats, Paddling, first item (Speed, Resistance, Energy).
I'd appreciate seeing more specific data.

You simply
claim that wave making resistance is not significant at paddling speeds.
For a kayak designed for optimal length at its cruising speed, skin
resistance and wave resistance are roughly equal.

I think you mean "wave making resistance". If you have a source for speed and
hull resistance numbers I'd appreciate seeing it. Wind and wave resistance
would be even better.


If a paddler is routinely using a kayak under conditions where skin friction
dominates, they'd be better off using a shorter kayak. If they are routinely
pushing against wave-making resistance, they should get a longer kayak.

Sorry it's not an inverse relation.


I don't think 10% is out of order in anything less than rough conditions.

You're still talking thru your hat, Willy. Unless you can cough up a valid
reference, I'll go with Brian's numbers.

Brian didn't provide any data. You can work it out from the data on my
website. I'd be interested in seeing more precise data than what I have. I
could only find generalizations at the time.


You should get out more. Rough conditions are when kayaking gets interesting.
The fact is that kayaks are used in rough conditions (as would be defined by
marine architects) _most_ of the time.

And where do you get that data, in your dreams?


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