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samdean

ILS not tracking correctly @ some airports

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I know this has been discussed before, but I was wondering if there was a resolution or at least acknowledgment that there is a known issue (or perhaps I'm doing something wrong): At some airports, I find the aircraft does not track towards the runway on an ILS approach. Recently, I tried ILS13 @ CYQR. Both NAV radios were tuned to the ILS frequency, I set course 135 on C and F/O MCP and the FD led me substantially to the right of the runway. Note the "auto-set FSX course" feature is enabled in my settings. Autoland also abandons the approach part way down... Is it a requirement that I get the magnetic variation BGL that's a sticky on these forums? Thanks folks,Sam Kharey

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I had the same problem. The solution is to turn off the ILS auto-tune feature. Regards,Mike Rose

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Mike - thank you. Do you mean I should disable the "auto tune FSX-CRS" feature? If so, then do I have to dial in the correct CRS manually (in accordance with FSX map?) Thanks,Sam Kharey

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I did a small investigation of this a few days ago.(i didnt check the forums for this issue before).I found out for my case(ils offset at certain airports), it was due to the difference in the "world" magnetic declination and the "airport" local magnetic declination. Then there is the heading information provided up the updated real world airac, but we keep this out of the picture because it doesnt affect ILS tracking. At that airport, (I just randomly pulled figures from the default FSX scenery, so may be different from yours), that particular lat, long, the global magnetic decl is E10, if you happen to update with the magnetic variation BGL. This may be true to real world.However the un-updated one is in the airport file. The airport file gives true heading of 138, and mag dec of E13 (old?) . This can't be updated by the global mag var BGL. You need to individually update the airport either by addon or some airport editor. So now you are flying towards the airport. What you see in the 737 heading is (true 138, E10) = 128auto-set FSX course will set 128 for you. But your going to drift to the right, because the ILS mag heading is (true 138 E13) = 125, even though its pointed at 128 (reference to global). To correct this, you dont auto set FSX course, and you tune both courses to 125 yourself, even though your heading towards the rw is 128, which slightly doesnt make sense. You will track the ILS in the centre. Of course, the only way to can find out the course of '125' is to pause, go to map, and click on the ILS to see the fsx given 125. But your charts may give another real world heading, like 130. And the AIRAC data in 737 is heading 130, your ND will be offset slightly(but this isnt the reason for ILS offset). My personal solution, is dont auto set FSX course, set it to what is initially shown, eg 130. Then once on it, if the plane is too much on the right, I decrease the courses, too much left, increase, until its centered, before 1500AGL. Another alternative is to edit the airport files, or have a real world scenery with accurate mag dec. Or set your global mag dec BGL date like 1994 so the mag dec becomes as old as the airport's. Others may have better solutions. Im just sharing mine, which is rather unrealistic but works for me. Marcus Jian

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I noticed this when I was flying into KCLT the other day. Can't remember which runway but I was way to high and was way to far to the west.

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The same thing happened to me on my last leg from VNKT-VECC (Calcutta). As I was approaching finals on runway 19L, I noticed that AP (Land 3) was not tracking the centerline accurately. There was no crosswind factor, only a 3-kt wind from the left. When I had runway visual at the decision height (100 ft RA according to chart) I had runway visual so I aborted the autoland and landed manually. I had the same experience before with the 747-8i back in Brunei airport, forgot the runway though...

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Isn't there a fix for that? If I'm not mistaking I once saw a link here to the fix...it could have been a post from Ryan I think...? Cheers,David DD

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should be a fix for this maybe in sp1 since many of us arehaving the same problem, we are bt catcgubg he ils, plane is not respnding to the numbers that we put into the radio system once we findout about what runway we are going to land at, and I'm at a 35 degree angle and still no movemment to catch the ils and definitely put in the tright numbers on radio and borth crouse dials hppened several times.

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I'm pretty sure it's an offset, unless the localizer diamond isn't in the middle.


xxwAU.pngUzJYY.png

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I have been seeing this problem with addon airports. Default FSX airports are no problem with the SET FSX LOC CRS on. However, at addon airports sometimes the switch should be either off or on and the course might be what current FAA Approach Plates show or it might be a different course. There is no pattern that I see. I thought maybe it was addons by certain companies or the age of the addons. To cite three that I have solved shows how variable the solution is. KTPA 01L CRS is 007. I use 007 with the switch off. KJFK 31L CRS is 315. I use 315 with the switch on. KORD CRS is 093. I use 090 with the switch off. A question for Marcus Jian. What are you doing about the F/O course display? ThanksMichael Cubine

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Oh, I place them exactly the same as what the pilot's course is. So if I decrease pilot from 90 to 88, i do the same for FO. If they arnt the same i think the autoland could get disconnected halfway or something? Previous/other planes do not have this problem because they do not take into account course settings. So its just fly straight down the ILS. But for this 737, course setting affects how much left or right your going to be on the loc. Since airport and global mag dec are diffferent at some airports, your 'correct' mag course to input isnt going to be the same as your actual mag heading. Global mag dec can be updated easily with the link Ryan provided. But for airports, its only updated for those custom airports install. Unless your patient enough to run through all ILS in the world to check for discrepancies. marcusjian

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Isn't there a fix for that? If I'm not mistaking I once saw a link here to the fix...it could have been a post from Ryan I think...? Cheers,David DD
If I recall correctly, the fix is to run the FSX registry repair tool available (free) from Flight 1.

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If I recall correctly, the fix is to run the FSX registry repair tool available (free) from Flight 1.
Thats more of a mythical fix than an actual working fix in my experience. I have run into this offset localizer issue on a few airports with a working registry. Running the registry repair tool didnt fix it for me. YMMV

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I have run the Flight 1 Registry Repair Tool several times over the past several weeks and it has made no difference in my issue. From what I remember it corrects situations where the plane is landing in the grass beside the runway as opposed to landing on the runway but left or right of the centerline. Michael Cubine

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