henra
"And btw. you don't create energy, you don't lose it, you can only change the form in which it is present. And that also depends on the frame of reference."
Show me please that I posited energy was "created"?
You make the mistake my esteemed opponent is making. Assumption after assumption. To gather an air mass and shape it such that it displaces and affiliates to the structure of the wing is impossible, in this universe. There is a flow, a sequence, that is not well served by constantly defining terms that allow a reversal of logic.
To the student, it is difficult enough to "fix" a wing, and parlay that into movement, outside the enclosed volume.
If you want to discuss a blown wing, fair enough, but to parse a gaseous volume into boundaries ahead of the entry of the wing is bizarre...