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Re: Pterosaur wings



david peters wrote:
> 
> Didn't Paul Macready already demonstrate with a working model that Q. could 
> fly _without_ the wing adduction that Jim C. is suggesting? Maybe I'm way 
> late ...

No, he didn't.  Paul and I know one another and at his request, have
given a talk together.  He's been a huge help to me.  But he built a
stand-off semi-scale model of Qn that used a totally unrealistic
semi-rigid wing structure.  He made no attempt to simulate actual
pterosaur wing structure and even deliberately used a reflexed airfoil
to reduce the nose-down pitching moment. I'm not knocking Paul for
that.  He knew at the time that Quetz didn't have a reflexed airfoil or
a semi-rigid wing, but among other things, he had no other effective way
to compensate for the retracted hindlimbs.  Paul is also well aware that
Quetz didn't fly with hindlimbs retracted, but they were one of the
design parameters. He also incorporated an impossible neck bend that
pulled the head in closer to the body to minimize the yaw problem
(something that quetz can't do). In my opinion, Paul is one of the best
(and may well be the best currently practising) aeronautical engineers
in the world.  That machine was superb, but even though more lightly
loade than the real animal, it could not maintain level flight in still
air, as was known at the time.  It is a wonderful craft, but does not
address a lot of the major issues of pterosaur flight.  Nor was it
intended to do so.  It is still a superb early effort and was useful in
many ways.  I'm glad it was done and would like to see it done again. 
As an aside, Sam Johnson of Johnson Wax provided $700,000 for the
construction of that replica.  I was recently asked by a different group
to put together a proposal to construct a full scale flying replica of
another, somewhat smaller species.  I cautioned the requestor about
sticker shock and then did so.  I could build one 16 foot span replica
for about $305,000 with additional copies for about $70,000 a pop. 
Those babies ain't cheap.  And they don't come with guarantees of
sucessful flight either.
Jim