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Old 25th October 2005 | 15:47
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R1Tamer
 
Joined: Nov 2004
Posts: 89
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From: USA & UK
Stick Migration

Looking at 'a book' to research some homework.

I note an interesting diagram plotting cyclic left/right displacement against airpseed.

It puts the cyclic to the left of centre at the hover.
It then moves right of centre at approx ten knots until approx 55 knots where it becomes approximately centred.
It then returns to left of centre from 55 knots up to presumably Vne

I'm pretty certain the diagram refers to a counter clockwise rotating helicopters

In my very limited understanding a cc rotating rotor will tend to tilt right at lower airspeeds i.e. 20 kts due to transverse flow effect requiring a left cyclic control pressure. As airpseed increases dysymmetry of lift becomes more prevalent but is dealt with by flapping and some fore/aft cyclic to control flapback but no lateral cyclic input to neutralise.

In other words I expected the cyclic to remain left of centre!

In brief terms can anyone elaborate on what other phenomena act on the rotor disc which would cause this cyclic displacement from left to right to left

Am I missing something obvious?

R1tamer
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