Hi,I have noticed that my 737NG has started to track parallel too, but half a dot to the left of the localizer beam. This is shown by the LOC dot on the PFD being slightly to the right of center line. Anybody got an expalnation as to why this might be?I wondered if it was something to do with using updated AIRAC data I obtain from Navigraph. As you know, north magnetic pole is shifting in real life and real world AIRAC data will take this into account. Obviously in FS9, magnetic north is staying where it originally was put by Microsoft. I dont quite know how this might cause this problem but it was just a thought.ThanksJohn Earl

Hi,I have noticed that my 737NG has started to track parallel too, but half a dot to the left of the localizer beam. This is shown by the LOC dot on the PFD being slightly to the right of center line. Anybody got an expalnation as to why this might be?I wondered if it was something to do with using updated AIRAC data I obtain from Navigraph. As you know, north magnetic pole is shifting in real life and real world AIRAC data will take this into account. Obviously in FS9, magnetic north is staying where it originally was put by Microsoft. I dont quite know how this might cause this problem but it was just a thought.ThanksJohn Earl

Hi John,Have you already checked the other threads covering similar (or identical problems)? There are plenty. Use keywords like "registry repair" and "ScanAFD.exe".If you already have done that, then more info would be useful (does the problem occur at one or all airport(s), add-on airports only, default AND add-on airports etc.). Finallly, posting a screenshot could help.And as far as I now, once you are on the ILS beam, AIRAC data becomes irrelevent. Even though your FMS might display a discrepancy message relative to the course selected, the plane will track the ILS beam (someone please correct me if I am wrong on this... ).Hope this helps,Bruno

Bruno is correct. The registry repair is the first suspect, and once the LOC is captured the aircraft tracks that and not the FMS course (in general terms, I think there is a real world interaction but we are talking msfs sim).The course discrepancy is due to the difference between LOC course in msfs and currently published. The currenly published value provided in the navdata file wpNavAPT.txt is what the FMS is crossing checking. However, localizers only have one course... fly the old fashion OBS steam guage in a C172 illustrates this. The CDI needle will center on the LOC course regardless of the OBS setting.There is a related problem with LOC that has to do with corrupt magdev.bgl files or add-on scenery but your description sounds like a registry problem.

Thanks Guys