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It's an instructor thing - instructors who rattle on about circulation and newtonian physics may be presenting a more accurate picture - but their students will never be able to build a mental model useful in flight from that explaination (evidence the post above).
Checkboard - assuming that you're referring to my post, my instructor has nothing to do with it. It's just my curiosity. I've got a PhD in Physics, and the explanation of the principles of flight that comes at PPL level is so obviously flawed (it isn't even dimensionally correct) that I went in search of a better one.
However, so far I've just used Denker's "See how it flies" and Barnard & Phillpot's "Aircraft Flight" (even with a PhD I find books without equations lighter reading...), neither of which deals with my query above - so I'm still not happy. However, I understand exactly what bookworm is getting at, so when I get the time I'll go find a book that doesn't leave the equations out and work through it.
I do like Genghis's Professor's version - I'll remember that next time I'm getting ready for a lecture on circulation...
