Re: FOUR, THREE, TWO, ONE . . . PTEROSAURS HAVE LIFT OFF!

[jrc <jrccea@bellsouth.net>]

My wife was hollering "Let's go, let's go", while I wrote the last post  I 
meant to type "plus the initial unfolding".  At the time the manus leaves 
the ground, the wingfinger has already accomplished roughly about 40 to 60% 
of its unfolding.  Due to the actinofibril function, the wingfinger membrane 
can operate somewhat autonomously from the inboard wing, so the unfolding 
can assist in powering 1) the initial lifting of the wing in the first 
upstroke, 2) the unfolding of the outer wing, and 3) initial acceleration of 
the animal as a whole.
JimC

----- Original Message ----- 
From: "jrc" <jrccea@bellsouth.net>
To: "David Peters" <davidpeters@att.net>
Cc: <dinosaur@usc.edu>
Sent: Friday, January 09, 2009 8:13 AM
Subject: Re: FOUR, THREE, TWO, ONE . . . PTEROSAURS HAVE LIFT OFF!


> More later, gotta go pick up my grandson.
> David, both your statements below are wrong.
> Also, the duration of the push off varies among species, but that plus the 
> unfolding takes almost exactly the same length of time as a flapping 
> downstroke for the same animal.
> JimC
>
> Dave wrote:
> At manus lift off, the metacarpus would, of necessity, still be
> vertical, having just pushed off the earth like a airborne pole
> vault. A vertical metacarpus means the wing finger was still in the
> vertical plane,