Hi!Lately I´ve been experiencing some lateral oscillations with PMDG planes which are apparently unrelated to weather shifts. The 737 at high altitude does a slight but constant left and right banking, like it´s trying to chase the route but overshoots it and tries to go back, and so on. The MD-11 stays on track, but every 5 minutes or so it does a pair of noticeable left-right 5 degree banks, stabilizes, and then does it again. All of this has been observed in FS9 and FSX on Windows 7 64, clean installs, clear weather with no winds, just running PMDG planes with latest updates and a registered version of FSUIPC. This is not the discussed S-turn issue cause the banking is limited to something like 5 degrees, but it still looks unreal to me, especially in no wind situations. I really don´t recall seeing this on my old Windows XP system, especially because it´s fairly noticeable. So, anyone has experienced this before and came with a solution, or is this really a normal behaviour for those planes?Thanks!!!Marcelo Torres

Hi Marcelo, First off, make sure you never run a flight with a highly detailed aircraft such as the PMDG's as a "Saved Default". That will cause a ton of issues as the Saved defaults get corrupt and in my opinion get mixed data.Since you have FSUIPC I would recommend setting a hot key in it (under the hot keys tab) to "Clear all weather". If you have any weather engine running it will just reload the weather after a few seconds, but clearing it will get rid of weather issues where there may be multiple data.The only other thing I can think of is running from cold and dark on the MD-11 I never have the problem, but I do see it once in a while if I just get in, program and go. I don't quite know why, but suspect that my TOCG data and other variables don't get modified correctly if I jump in the started one, set my fuel, program and go. I never miss a step (well, not anymore ;-) but again, never have the issue from cold and dark that I can ever remember.Hope this helps,

I assume you've already checked that yaw dampers are on :)My default flight is the default Beach Baron or King Air parked cold and dark. These initialize the FS engine even when in the menu stage and are sticky when creating a flight. Always use a default relatively simple aircraft for your default flight like Turbine 777 recommends.

Dan and Ron,Thank you very much for your inputs, but unfortunately the issue still persists even after creating a cold and dark default flight. I´ll try to have access to a Windows XP system to check if this issue is related to Windows 7, as I really don´t remember having this problem on XP. If anyone else has a potential solution, feel free to write it down here.Thanks again!!!Marcelo Torres

I have not seen this issue before and I am on Windows 7 64 and fly the MD-11 almost every night, not to say it's not Win 7 but it could be something with your weather apps / install of them. Try running a default weather theme in FSX, how does that work? After initially switching from Vista 64 to Win 7 64 I had all kinds of issues, I soon realized that right-clicking and selecting "Run As Administrator" for all installs and starting applications helped resolve all my issues. Be sure that you are doing this evertime you install/run FSX or any other program that communicates with it, it will cause issues if you don't. Hope that helps any! - Jeff Johnson

Outside possibility, but can you check if 1) you are running in compatibility mode, and if so, 2) are you running in XP SP2 mode, and if so 3) does the problem go away if you change to XP SP3 mode?Gustuv suggested this in the thread Uncommand deviations... but at the moment, there is no evidence to suggest it will help.