Quote:
Originally Posted by euromodder
So ... birds use Coanda in order not to stall out.
At speed, the feathers would remain flush.
They lift as AoA increases, like a spoiler dumping lift, lowering AoA again before it gets out of hand (i.e. stalls out).
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I believe that as the angle of attack reaches burble point the feathers are lifted into the low pressure of the turbulence.
Depending upon the birds intentions it can deploy its tail feathers and land on something,or it can morph to decrease the AOA,restoring a 'clean' configuration.
Or,as with the Peregrine falcon,it can tuck everything in close to its body and bound towards Earth at over 200 mph in its stoop.