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Re: The origin of flight: from the water up




David Marjanovic wrote:

> > If they were to enter a wave with
> > their wings extended, instantaneous lift and drag forces would increase
> > by a factor of more than 800.  That could put some serious stress on the
> > joints.
>
> Yet some birds do it (don't know just how extended their wings are).

If they did it with wings fully extended, then the factor of safety in the
wing structure would have to be about 400 or so, considerably above the usual
3 or thereabouts.  How does one go about increasing the normal strength of
these extended wings by more than a hundred times?

> > And however they get in, flapping around underwater is common.

Of course.  But after decelerating and at a reduced velocity and flapping
frequency.  They tend to avoid doing things that are structurally impossible.

> OK... fast flapping might not. The first (relatively slow) downstroke,
> though, certainly would, wouldn't it? :-)

I don't see any reason why it would.  Please explain it to me (in words of one
syllable or less -- I'm not too sharp).

All the best,

JimC

P.S.  I may not respond immediately.  I have a sick friend in Florida and may
have to be out of pocket for a while.