It has been years since I read RCUniverse. I hope that I can still handle a response.
First I must know if the model is exhibiting the following characteristic. What I am thinking of is when the acft likes to fly stably in either a right wing down yawing left or flops over to fly left wing down and yawing right. As an aero engineer I have witnessed this phenomena in the Langley free flight wind tunnel and can address the exact cause of the lateral instability and can suggest a simple fix. Are we talking about the same thing?
Nathan Rambo.
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