Re: Fin shapes

RMTT wrote: 
Ad Brandt wrote:

J Flory wrote:

- stability - a less stable hull may require a skeg with a greater
stabilizing effect on lateral roll, again depending on the designer's
expectation of the users' skill levels
-  the hull's intrinsic tracking ability - a hull with a deeper bow
(Filippi, Hudson, Empacher) may naturally track straighter than one
with more rocker (van Dusen, Resolute) and hence a smaller skeg may




Slightly off-topic, but now that you mention hull shape, I'd like to ask this question:
what's the advantage of rocker, ie the bow coming out of the water for something like half a metre of length when the rower is in the catch position? This half metre seems useless at that point and thus dead weight, and just before the catch when the boat speed is at its maximum, you probably need all the waterline length you could get! Isn't that the reason that modern sailing yachts have completely abandoned rocker and have these straight, perpendicular bows?

~Ad

Just thought of a reason why you want rocker on a shell's bow: when you move towards the bows during your stroke, the CG moves forward, the bows move down into the water. However, a bow with rocker will increase submerged volume forward, and therefore pitch less. 

You sure about that, Rutger?

Must be why a rocking chair keeps so still when you move back & fore on it. Wonder why they call it a "rocking chair"

;)
Carl

--
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Relevant Pages

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    ... the hull's intrinsic tracking ability - a hull with a deeper bow may naturally track straighter than one with more rocker and hence a smaller skeg may ... Slightly off-topic, but now that you mention hull shape, I'd like to ask this question: ... This half metre seems useless at that point and thus dead weight, and just before the catch when the boat speed is at its maximum, you probably need all the waterline length you could get! ...
    (rec.sport.rowing)
  • Re: Fin shapes
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