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Old 7th Sep 2013, 05:27
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Aotw - you are completely correct and I know where the confusion between myself and AnFI has occurred:

On all the helos I have flown, all (bar the R22) have hydraulic jacks and are considerably bigger and heavier. As I said in my last post, they all use a combination of jack position and advance angle to ensure that max or min pitch is achieved 90 degrees before the desired high or low point.

Often, half of the angle is taken out with the jack positioning and half with the advance angle such that pure forward cyclic would tilt the swashplate to the half-past one position and the 45 degree advance angle obtained by putting the pitch change arm ahead pf the feathering axis would complete the job.

What I forgot, in my hazy recollection of the R22, is that the pitch change horn is mounted pretty much 90 degrees ahead of the feathering axis so that the swashplate does tilt forward with the cyclic.

This is the problem with arguing about helicopters since there are so many different designs which achieve the same effect in different ways.

Hopefully AnFI will agree that if there was no advance angle on a rotor system and the pitch change arm was exactly on the feathering axis, then to achieve a blade low at the front would require the swash plate to be tilted to the right - this was the picture in my head of a basic control orbit.
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