Re: Quetzalcoatlus may have lived like a giant stork

[jrc <jrccea@bellsouth.net>]

----- Original Message ----- 
From: "Michael Habib" <mhabib5@jhmi.edu>
To: <dinosaur@usc.edu>
Sent: Friday, September 21, 2007 3:11 PM
Subject: Re: Quetzalcoatlus may have lived like a giant stork


> The reduced span does subtract a bit from gliding efficiency, but reducing 
> the distal wing also reduces wing inertia a great deal (which improves 
> flapping ability).

Another point which is quite obvious but which no one ever seems to mention, 
is that these animals can change their aspect ratio at will within 
reasonably broad limits.  For example, when traveling by means of microlift, 
cloud streets, and turbulence, they can extend the wingspan and narrow the 
wing to increase the aspect ratio and lower the induced drag.  When 
loitering, they can retract the wing slightly by swinging aftward at the 
wingfinger pivot and the wrist while swinging forward at the elbow, thus 
broadening the outer wing while shortening the overall span in order to 
better utilize thermal rings when so desired.  They also make these changes 
during every flapping stroke.
JimC