Re: Fin shapes

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

One of the reasons yachts have perpendicular bows has to do with design-rules: many classes use a box-rule: Yacht shall not be longer than X feet *measured between perpendiculars*. And as waterline length increases speed, the bow is designed to be perpendicular.

Rutger
.

Relevant Pages

  • Re: Fin shapes
    ... 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
    ... 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
    ... 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)
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