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Old 6th Sep 2013, 16:53
  #20 (permalink)  
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You also said: ".....countered with more FORWARD cyclic (right swashplate movement)."
That is also incorrect : forward stick tilts the swashplate forwards.
Sorry AnFI but forward cyclic tilts the disc forward but the swashplate right.

In order to obtain a disc forward attitude, the minimum pitch must be on the right hand side - this gives maximum rate of flapping down and a low point 90 degrees or so later (at the front in this case) This is phase lag.

Phase lag on the R22 seems to be greater than 90 degrees since forward cyclic is clearly giving an element of left roll - I had missed that part so we were arguing from different directions.

Baobab started the thread with a question about transverse flow which I answered - then I made the mistake of including the lateral trim in the R22 as part of my argument; on that part I was wrong but I thought your argument was not only about the R22 ( about which I was wrong) but also about inflow roll (about which I am correct).

So, some mis-communication there and me jumping to some incorrect conclusions for which I apologise unreservedly.

However, you might want to review the relationship between the cyclic movement and the swash-plate.

The Lynx doesn't have a swash plate, it has a spider arrangement but it does essentially the same thing - every other helicopter I have flown has had a swash plate that tilts towards the advancing side to achieve a disc low at the front. I have flown aircraft with different arrangements of jack positioning and pitch change advance angle but they have all been to exert a minimum or maximum pitch angle 90 degrees ahead of where the lowest or highest point of flapping is required.

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Last edited by [email protected]; 6th Sep 2013 at 16:54.
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