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Re: S&G: looking for S&G canoe design
By:Mike Savage
Date: 12/31/2007, 6:38 am
In Response To: Re: S&G: looking for S&G canoe design (Chris Ostlind)

: Charlie,

: Perhaps it would be good to understand that the people, especially in this
: case, ARE the weight. That they move around, as you suggest, only makes
: for a more complex weight management understanding for the designer, as
: well as the principal paddlers (stabilizers) of said boat.

: To attempt to isolate the passengers, as some other type of displacement is
: just an attempt to comfortably remove them from the direct issue at hand.

: If you want to be perfectly honest about the whole weight carrying issue for
: any boat, no matter the size, weight-shifting issues are one of the very
: large design concerns for anyone who wishes to create a boat.

: Take a look at how many containers are lost at sea annually from very large
: cargo vessels. Do you think that these containers just might be shifting
: around, even a little, on board the vessel before they finally let go from
: their fastening devices and fall over board?

: Before you get all wiggly on this, the answer is they do. That shifting of
: cargo, as an assigned displacement weight, sends chills through designers.
: And yet, those are not people at all, just simple lashed cargo containers,
: which are supposed to remain intact and stable throughout the voyage.

: These same things can happen in any canoe and professional longshoremen do
: not lash them down. Imagine, for just one moment, just how much a typical
: canoe cargo will move about while the boat is underway, even without any
: turbulent water like one might see in a serious, Class 3 rapid.

: It's the nature of the beast, Charlie.

: And, Charlie? human beings do not have innate aversions to sitting down low
: in their vessels, as one might ask of their human cargo in a large canoe
: of this suggested type. Otherwise, what are all those kayakers doing when
: they place their seating as low as possible for day long paddling trips?

: Joerg is always free to take the canoe to the shore of the Danube (Donau)
: where he can easily trade places with anyone on board, so that the entire
: crew are integrated in the boat's propulsion and steerage while also being
: able to switch from a relatively idle posture to one of full activity.

Hi Chris,
Interesting point about stability and shifting cargo but there is a small flaw in it. I have yet to see a shifted container move back to its correct position on its own, people can, and do.
There's also awareness of 'cargo' behaviour. One doesn't really expect fixed cargo to shift about, while it is expected that people will move about a bit. In a canoe, this is something that can be adjusted for fairly easily and automatically.
The difference between static and dynamic weights, perhaps?

A reason not to use bungie-cord as cargo tie-downs. :)

Mike Savage
South West Cork

Messages In This Thread

S&G: looking for S&G canoe design
Joerg -- 12/29/2007, 9:22 am
A desin to consider modifying
Paul G. Jacobson -- 1/5/2008, 5:27 pm
Re: S&G: looking for S&G canoe design
TOM RAYMOND -- 1/2/2008, 3:52 pm
Re: S&G: looking for S&G canoe design
Chris Ostlind -- 1/2/2008, 6:10 pm
Re: S&G: looking for S&G canoe design
TOM RAYMOND -- 1/3/2008, 8:30 am
Re: S&G: looking for S&G canoe design
Paul G. Jacobson -- 12/31/2007, 4:30 am
Re: S&G: looking for S&G canoe design
Charlie -- 12/30/2007, 1:44 pm
Re: S&G: looking for S&G canoe design
Chris Ostlind -- 12/30/2007, 8:33 pm
Re: S&G: looking for S&G canoe design
Mike Savage -- 12/31/2007, 6:38 am
Re: S&G: looking for S&G canoe design
Mike Scarborough -- 12/30/2007, 12:34 pm
Re: S&G: looking for S&G canoe design
John Van Buren -- 12/29/2007, 5:07 pm