In my last 10 flights, gradually ILS started to not lining up with RWY center line. First I thought maybe Navigraph data has some problems, I began to close monitor ILS progress. AP trying to intercept the signal, but plane keep moving left (no cross wind . no less power in one engine, all trims in centerline, no flap/spolier and controls problems) Yesterday night during AP in autolandmode to KJFK 31L approach. MD-11 was realy off to left. If I didnt takeover the yoke , MD-11X was going land off the runway.Will you please inform, What is causing this problem? How can I correct ILS errors?ThanksSanal

I noticed this behaviour once with a couple of ILS approaches... I used the Flight1 freeware registry fix tool available on their site...Fixed the issue...Andrew

See also: http://ops.precisionmanuals.com/wiki/How_t...Tracking_Errors

Thanks for your reply. I tried several times to install Fligh1 registry tool. I dont know if it is installed or not. How shall I use the "Tool"regardsSanal

Just execute the exe file... that is it... done...And check out Dan's link too... one I forget all the time, thanks Dan!Andrew

Worked for me too. Now both MD11 and FSX B744 track the ILS perfectly.Some hint to know if the problem maybe a registry problem with FSX:

1. Enter a simple flight plan into FMC, and add a waypoint directly on the abound of the dep rwy. If it is shifted to the left or right in the MAP mode of HSI that is clue 1.Next at FL if the airplane appears to be tracking opposite of the wind direction, clue 2.Finally, when doing an ILS approach, do a hands off and let it land. After it lands if it tracks quickly back to your intended rwy, clue 3.Summary, if the above happens use the registry fix for sure.