GNU Terry Pratchett
https://en.wikipedia.org/wiki/Bombardier_beetle
(on a much smaller scale)
Once you have technology that enables flapping type motion, it's opening up the applicable physics to like 6 degrees of freedom versus zero in current wing technology (fixed = 0 degree of freedom); much more complex and interesting to study.
How else will we move toward ornithopter style wings, or vehicles that can hover via wing movement.
I guess “supersonic wing flapping” would have similar problems, but maybe there are more clever solutions than can be modeled, with so much degree of freedom?
And is “supersonic flapping” even possible?
Where else could it possibly go?
Grossly speaking, sure. But I feel like this simplifies away a lot of the interesting bits. It's not as simple as, say, someone on a canoe paddling. Why is the duck's wing shaped just so, and not another way? Why does it move its wings just so instead of another way?
I'm reminded of an analysis of fruit fly wings, showing how they re-capture energy from the air when flapping[1]. Maybe the duck is doing similar; I don't know.
Of course, these animals make it look easy, thanks to millions of years of evolution (:
Also, in my experience there’s a huge difference between having an intuition for something and having an understanding of something to the point where you could model it.
I guess I struggle with articles like this because it's already so intuitive as a mix of air and fluid dynamics. In fact, fixed airfoils are so boring when you see what a duck can do.
https://www.youtube.com/watch?v=-3CVZYY8xS4
So for all the fancy physics talk, this duck is literally just paddling air with his wings. The same physiology I use to stay afloat when treading water while swimming.