Re: [Paddlewise] QCC boats and water line length ........

> Matt Broze wrote:
> snip <
> ...  but it did point out the much bigger benefits of loading the
> heavier items close to the middle and lighter ones in the ends 
> when kayak camping.  But based on the information in the article 
> shouldn't the paddlers in an open canoe sit close together in the 
> middle rather than out near the ends.  That would decrease its 
> gyradius (or Equivalent Arm--EA) by many orders of magnitude 
> not just the small increase more bow rake in the ends would 
> cause (if waterline length is the chosen constant). I bow to you 
> as my best source of expertise in open canoe design John. 
> Please explain to me why open canoe paddlers sit so far away 
> from each other--do they learn to hate each other so much that 
> they choose to suffer the serious effects of their extremely 
> increased moment of inertia to stay out of range of a canoe 
> paddle swung in malice? 

Designs of different craft spring from the use of the craft during the
evolution of the design, as I'm sure you know.  
The comment about seal hunters not wanting bow overhang in their 
kayaks slapping the water in waves is one illustration of the 
application affecting the design.  Without pretending to be an expert
of canoe design (or John), I offer the following as possible reasons:

a) The open canoe at one point of its historical development was not a
recreational craft, but a freighter.  Rivers were the only 'roads' around,
and transport of goods was what the canoe was designed for.  
The paddlers sat nearer the ends to provide more cargo space
amidships.  Today's trippers still need the cargo capacity.

b) With paddlers near the ends of the boat, there is much more control in
crossing current differentials, which is the trickiest part of river
paddling, as one has to contend with different forces pushing different
parts of the boat (open water paddlers have tide rips and breaking surf to
offer the same challenges).   Making an eddy turn with a loaded tandem open
canoe (or any longer boat, loaded or not) requires that the boat stall out
on the eddy line, with the bow in the eddy and the stern still in the
current.  Tandem canoeists near the ends of the boats have more leverage to
put - or hold - the end of the boat where they want it.    


> (I can see all sorts of reasons why closed tandem slalom canoeists
> shoved their cockpits right together roughly twenty years ago. Passing
> through narrow slalom gates sideways, not having to wait until the second
> paddler 10+ feet away cleared the gate to turn, the new art of gate
> sneaking, yaw gyradius, pitch gyradius. Just a few.-)
> 
Slalom boats are also application specific designs.  One additional
constraint here are minimum length requirements that most racing boats (of
any type) must meet.  Makes me wonder what slalom boats would look like if
there were no restrictions imposed on the design?  I'd venure a guess that
they'd be much shorter.

Play Hard,
Erik Sprenne 


***************************************************************************
PaddleWise Paddling Mailing List
Submissions:     paddlewise_at_lists.intelenet.net
Subscriptions:   paddlewise-request_at_lists.intelenet.net
Website:         http://www.paddlewise.net/
***************************************************************************