PPRuNe Forums - View Single Post - Helicopter Lift Theory - Equal Transit, Skipping Stone & 1/2 a Venturi - all wrong...
Old 17th November 2012 | 03:18
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paco
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From: White Waltham, Prestwick & Calgary
I know someone who was trying to revise the Rotorcraft book but was bombed out because they just didn't want the changes. Did they finally get the tail rotor drift diagram right? I had to point out that the arrows were going the wrong way.

We have the same problem in Europe - according to EASA, the only reason aerofoils produce lift is because of the upper surface reduction in pressure, in the first 25% of chord.

So tell me - based on that, where do helicopters get downwash from? They should read Stick and Rudder!

Like you, I find it frustrating to have to say "this is what they want in the exams, but this is what really happens!" Which is what we do, otherwise they will not pass the exams in the first place (with the lies), or the tech interviews after that (the truth).

The truth is that all those theories work in combination. None of them work entirely alone.

Last edited by paco; 17th November 2012 at 03:21.
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