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Re: Naive WAIR Question



Mike Taylor wrote:
> 
> Isn't there also something in the morphology of extant avian feathers
> that inherently suits them for generating upthrust?  I am no expert,
> but I seem to recall that the cross-sectional profile of a flight
> feather is curved in much the same way as the wing itself.  Is this a
> correct recollection?  If so, then you'd think that those WAIRing
> dinobirds that were best adapted for WAIRing would be precisely those
> that were _least_ adapted for flight.

The feather curvature doesn't affect the slope of the lift curve.  Only
the aoa for zero lift, and to some extent, the drag.  I don't see it as
a big deal. And it only has those effects when the feathers are
seperated and the flow is also transverse to the feather (roughly
parallel to the chord).  Note that hummingbirds generate lift on both
the 'down' and 'up' strokes by partially inverting their wings.

> 
> What am I missing?

I think mostly the lift curve slope.