This question already has an answer here:

One explanation I read:

Because of the wing's geometry, the "upper" side of the wing is longer, so the air has to travel faster:

enter image description here

My wondering: Who said (and what was his/her explanation) that air must travel the distance above and under the wing in the same time?

I'll try to be clearer. Considering the below image, does m1 and m2 meets at the same point exactly at the same time on point T?

enter image description here


marked as duplicate by DavePhD, Brandon Enright, Kyle Oman, Colin McFaul, Kyle Kanos Jun 11 '14 at 17:50

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

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    $\begingroup$ possible duplicate of What really allows airplanes to fly? $\endgroup$ – DavePhD Jun 11 '14 at 16:00
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    $\begingroup$ Please read this question (and the associated answers) first. If you have any further questions please explain. $\endgroup$ – OSE Jun 11 '14 at 16:00
  • $\begingroup$ Thanks, somehow I couldn't find the duplicates when I posted the question. Will look at the answers there and see if they answer my question. $\endgroup$ – Maroun Jun 11 '14 at 16:02
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    $\begingroup$ It is a recurring, and absolutely wrong, conception that the air has to rejoin itself at the trailing edge. In fact, wings could not work if it did, because lift requires circulation. Check this very good explanation. $\endgroup$ – Mike Dunlavey Jun 12 '14 at 11:20
  • $\begingroup$ The short answer is no, the adjacent air molecules do not meet up at T. As for who first said it, that's a good question - the Equal Transit Time Fallacy (ETT) first appeared in the mid 30s, some three decades after the wright brothers flew at Kitty Hawk and several thousand years after sailors figured out how to use lift to propel boats. For some reason, the US military taught this nonsensical explanation in WWII and it's been repeated so often that its hard to dislodge. the Equal Transit Time Fallacy is false, but a very common misconception. $\endgroup$ – Paul Townsend Aug 25 '15 at 20:45