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Here's a challenge professor. If you can explain dissymmetry of lift (helicopter) without punching a hole in your 'wind has no effect' theory than I'll admit I was wrong and might enroll in one of your classes.[img][/img]</p></font>
Relative wind is completely different then the moving airmass we feel as wind on the ground. Dissymmetry of lift is a factor even on calm days. Note the term "relative wind". Still no holes.