http://forum.avsim.n...turns-nav-mode/

 

 

Hello all,

 

With reference to the problem previously encountered by a few other people (see link), this issue has popped up for me recently on two successive flights.

 

En-route from CYVR to CYEG, approximately half way through the flight, the aircraft began a right turn off course and exceeded the bank limit. I switched to the other autopilot; however, the same problem occurred again. The rest of the flight was flown manually.

 

Then again from CYEG to CYOW, the problem resurfaced. Interested to see how unusual a configuration the autopilot would develop, I allowed it to proceed. The aircraft was unable to maintain altitude, and began to roll inverted.

 

I understand this may have been corrected with various hotfixes and SPs. I have the latest SP1c installed, and have made no modifications to my set-up aside from installing REX Essential. My thoughts are this might be related to the weather engine, as both incidents occurred within minutes of your every-day high altitude FSX windshear.

 

Thanks in advance for any thoughts,

This is a very well known and well documented issue. Its caused by the inaccurate way FSX deals with weather, especially turbulence. Disable turbulence in your weather engine and enable wind direction change smoothing and the so-called s-turns should disappear