HIThe Title says it all (under FS9)Very strangeHappened several times, in flight or before departure, randomlyI made sure I am using the original magdec.bgl from disk3.Uisng latest FSUIPC as wellDon't understand...Has someone experienced the same?Thank youGhiom Viguie

I have the same problem. Only mine occurs with any aircraft I fly. I keep hearing that the Airac uses current data and the files in the magdec are static or old data. I hear you have to update your scenery but i have a ton of scenery and 95% dont have any updates. I never had this problem before either. It started with the last two Airac versions 710 and 711. i dont know what else to do or how to fix it. Any ideas, anyoneWill

Thanks for your replyAlways glad not to be the only oneTrue, it happens with all a/c...What I personally did is to revert to an older airac.It worked for 1 flight. during the 2nd flight, 3/4 away, I got the problem again...the A/C not managing to follow the path and flying in crab.Anyone's got other ideas?Regards, Ghiom

BingoThis morning, 1st launch of FS9 and heading 298 on SFO's 28R!!!!Why???I did nothing from yesterday on?Incredible.Thank you for your help.Ghiom

Anybody know if the 9.1 patch changed the magdec.bgl from the disk version?

Any time we've seen magvar problems happen it's usually been because of conflicting addon scenery. You can still have the original magdec.bgl and see the problem because the addon overrides it. It can also be an addon anywhere in the FS world, it doesn't have to be the local area you're in.My first troubleshooting step would be to disable all addon sceneries, see if the problem is fixed, and then go through reenabling them one by one until you find the one that's doing it.

Thank you for your helpI have played with my addon scenery activation and I think I found the culprit:It seems to be KMAF - Midland/Odessa,Texas, by Joe DeGregorio / FlightLevel390.Here is the link in the library http://library.avsim.net/sendfile.php?Loca...ftp&DLID=112059Can someone try and tell me if he sees the problem?Thank you again.Ghiom

There's an updated magdec.bgl in the free library that I've been using without any problems. I think it's from 2006, not 100% sure, but it's better than nothing. Otherwise, it's usually a scenery conflict.