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Re: Eudimorphodon workshop (not so) short report

Silvio Renesto wrote:
> At 08.18 10/11/2003 -0800, Jim Cunningham wrote:
Silvio wrote:

> >Indeed I was meaning LOW WING
> >LOADING.  According to Chris The anurognathids had a low wing loading
> >which may have permitted, among other factors a somewhat slower flying
> >speed

Indeed it does.  Other things being equal, the flight speed will be
proportional to the square root of the ratio of the two wingloadings. 
Halve the wingloading, and you reduce the flight speed by about 29%. And
for a given wing, halving the wingloading will reduce the sink rate by
about 29% as well.  For a given wing, the glide ratio will remain

> and the less stiff articulation between  wing phalanges may have
> >allowed more manoeuvrability,

Quite true as well.  Ventrally cupping the articulations between
phalanges IV-1&2 and between PhIV-2&3 on one wing will simultaneously
increase both the angle of attack and the camber of that wing, each of
which will raise that wing and institute a turn toward the side away
from the wing.  However, adverse yaw may be considerable in some
circumstances, and the animal itself may rotate in the direction
opposite from the turn unless it simultaneously takes additional action
to compensate.  'Decupping' the wing will have the inverse effect. 
However, decupping the wing can lead to reducing the aeroelastic number
of the membrane below the flutter limit or the bistable limit, and can
lead to catastrophic controllability issues.  Fun stuff to think about. 
These joints in the  Quetz phalanges allow just this sort of movement.

> I post this reply on the entire list to make it clear,  in the hope that I
> haven't irrevocably made a fool of myself forever.

Not at all.  I was pretty sure you were referring to low wing loading,
but wanted to assure myself that that was indeed the fact.

All the best,
P.S.  Wish I could have been at the workshop.  Thanks for reporting on