Smaller, Lighter Wings???

Eagles in flight give us a hint on how to make smaller, ligher wings; shorter keels; or less intrusive wind turbine blades.   The key is the tip feathers.  I wanted to know how effective these feathers might be so I used MultiSurface Aerodynamics to perform a simple test.  The figure below shows the results of this test.

In the experiment, I tested three wings.  The first wing had an aspect ratio of 4; the second had an aspect ratio of 6; the third had an aspect ratio of 4 along with wing sails (tip feathers).  The above figure shows that the wing sails elevated the performance of the wing with an aspect ratio of 4 to that of the wing with an aspect ratio of 6.

The MultiSurface Aerodynamics analysis provides proof that taking hints from nature can improve engineering structures.