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Re: 11th specimen of Archaeopteryx



On 10/28/2011 3:03 PM, Jason Brougham wrote:

Dr. Habib, did you write once that mathematical aerodynamic models show a 
reduction of performance if there is a gap between the secondaries and the body 
wall?

Perhaps irrelevant, but -- I once did wing mutilation experiments on Carpenter Bees (X. virginica) that entailed cooling the bees to "anesthetize" them, clipping the wing ends incrementally and then placing them in a pressure-controlled test-chamber to see if they could achieve "lift-off".

Bees w/ literally half a wing could still become briefly airborne -- and when ambient pressure in the chamber was increased to 2-3 atm, thereby increasing the density, sustained hovering (~30 seconds) was achieved.

My point, relative to this thread -- I also tried clipping the secondaries only, which created a gap between wing and body -- these bees apparently could not generate lift under any density conditions.

The inboard wing is important, at least to these animals.

Also -- domesticated mallard ducks fly well -- it is a traditional husbandry practice to clip their feathers periodically to keep them close to home. This offers both a body of practical knowledge, and the opportunity to experiment...