Peregrine falcons have blue feathers atop their heads and on their backs. Males tend to be more brightly colored than females, so if you've seen one with a more grayish-blue coloring, it could have been a sex difference.
And yes, aeronautic design borrows a lot from birds. 😅
(Also, a peregrine's nose connects around to the back of its head. It breathes in through the front and out through the back. Like a turbine.)
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And yes, aeronautic design borrows a lot from birds. 😅
(Also, a peregrine's nose connects around to the back of its head. It breathes in through the front and out through the back. Like a turbine.)