Re: HydroDynamic Lifting

"Neil Wallace" <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>...
> Bill Atkinson wrote:
> snip
 
> 
> Bill,
> 
> This page is v. interesting http://www.atkinsopht.com/row/bladwing.htm
> 
> a couple of questions though.
> 1. why isn't the weight of the plane acting in the direction of the vertical
> reference?

The plane's weight IS in the direction of the vertical reference; the
two vectors are parallel.  Perhaps the diagram could be clearer.
> 
> 2. Isn't this statement at odds with the biomechanics of rowing??
> ..........start quote.........
> "the lift and drag characteristics of an oarblade have no more effect on the
> rower's propulsive force than the lift characteristics of a wing have on the
> weight of the airplane"
> ..........end quote...........
> extreme example, give me NO lift or drag, I would produce much less force
> (but quicker?)

Yes, "but quicker". With no (or very small) drag (as with a very
narrow blade) one would have to pull through very rapidly to generate
some particular and significant reaction force.  BUT, this SAME
reaction force could be attained with any other "blade" depending only
on the pull-through speed. Theoretically all blades can produce any
given propulsive force, the only difference between them being their
slip (hydrodynamic) characteristic which, as we see, has nothing to do
with the force attained.

Thanks for your thorough interest.
Bill 
> 
> Neil