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Approaches still mis-aligned after MagDec.bgl update

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I have updated the MagDec.bgl in FSX, following the install instructions to the T but for the life of me I cannot get the magenta approach path to line up with the extended runway centerlines on the ND. I've fixed this problem before by using the newest MagDec but it just doesn't work anymore. Anyone else experience this? 

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I'd try using the Flight1 fsx registry fix tool. This sorted out the problem for me.

 

Don't have a link with me - but Google will find it easily.

 

Cheers

 

 

 

Paul Hand

Sent from my iPad using Tapatalk HD


Paul Hand

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I'd try using the Flight1 fsx registry fix tool. This sorted out the problem for me.

 

Don't have a link with me - but Google will find it easily.

 

Cheers

 

 

 

Paul Hand

Sent from my iPad using Tapatalk HD

 

 

Thanks. I've tried that already and didn't work. I've also made sure the magdec is the last scenery layer being loaded and I made sure my scenery.cfg isn't out of order. This is very strange and annoying. 

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Use the solution posted here by Ryan: http://forum.avsim.net/topic/288086-747x-ils-tracking-issues/?p=1798292

 

Although I'm not sure if it will fix the 737, I though only older addons were affected by corrupted facilities data.

 

 

Darn, I honestly thought that was the solution since I had never seen that before but alas, that didn't fix it. Thanks though. 

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After doing some research I've learned a few things:

 

1. Using the latest available AIRAC, the NGX FMC is drawing the magenta line using the correct approach course (ex.: KSAT 12R is 127 IRL and 127 in the NGX)

2. When I load the NGX on that same runway (12R KSAT), the SHIFT+Z HDG readout is 127, which is again, correct. 

3. When I use FSX's Map function to look up the runway course, it shows the incorrect and outdated heading, which is 124. 

4. The runway and extended runway centerline drawn on the ND in the NGX is also incorrect, at 124. 

 

 

I don't know how this helps, but the investigation continues... 

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I too have updated the MagDec.bgl file. I'm still getting some runways miss aligned. I have FTX Global. Not all runways have been miss aligned only a few. I will try and find out which ones are but I'm not at home at the moment. It doesn't seem to be an aircraft thing with me, it doesn't matter what aircraft I'm in if the ILS doesn't align in one aircraft it won't align in any. I haven't tried Ryans fix for the 747 yet I will when I get home.

I think when I do get a misaligned ILS the published heading for the runways is usually different to the heading in FSX don't know if that helps. I also use EFB and the heading in that is usually different to the charts as well.

 

Regards,

 

Fly UK - Head of Operations

 

Jordan McTiffin

 

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After doing some research I've learned a few things:

 

1. Using the latest available AIRAC, the NGX FMC is drawing the magenta line using the correct approach course (ex.: KSAT 12R is 127 IRL and 127 in the NGX)

2. When I load the NGX on that same runway (12R KSAT), the SHIFT+Z HDG readout is 127, which is again, correct. 

3. When I use FSX's Map function to look up the runway course, it shows the incorrect and outdated heading, which is 124. 

4. The runway and extended runway centerline drawn on the ND in the NGX is also incorrect, at 124. 

 

 

I don't know how this helps, but the investigation continues... 

 

I had 125 as the runway and the extended centerline on the ND when I just tried it.

 

Regards,

 

EDIT: Actually no I just tried it again and I got 124, not sure what I done wrong the first time.

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This is still screwed up even after a complete uninstall of FSX, registry fixes, rebuilding facilities/scenerycache, updating all navdata, etc. etc etc. Is there anyone who can provide me some advice? This is getting frustrating. 

 

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NZz4f9A.png

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Skyvector lists the following data for KSAT 12R

 

Runway Heading: 124° Magnetic, 132° True

 

 

The default FSX runway heading is 131.71 true

 

Inbound course of 127 is correct, I don't believe there is actually an issue in this instance, the approach is not on the centre line.

 

EDIT: If you look at the missed approach procedure, Fly runway heading of 124!

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The problem you mention is due to the fact several displayed magnetic headings in FSX (and FS9) do not depend on the "global" magdec data but on magnetic variation that are individually set for specific airports inside BGL files. This is the case for FSX map display. I don't know what information NG uses.

Here KSAT data are contained in the APX21210.bgl file and are defined as follows:

Rwy 12R true heading: 131.7°

Airport magnetic variation (as defined in the BGL file): 8°E

Consequently the "FS" rwy centerline magnetic heading is 124°

Real 2010 data indicates the magnetic variation at KSAT is now 5°E; consequently the magnetic runway heading should be indeed 127°!

 

Note the same is true for ILS magnetic headings as displayed on FS maps, as far as they also have their own magnetic variation information

 

There is no simple solution for correcting that by now unless you are able to change the airport magnetic variation inside the BGL file.

 

Hope it will help

 

(Edit later on): You will find in the MagDec_Update.zip package a small utility called BGL Magnetic Variation Corrector that is able to update these magnetic variation data directly inside BGL files. You may have a try to it but take care. As a precaution, only select airport data (you may also include ILS but do not select the other facilities i.e. VOR, NDB and intersections) and only modify the file you are interested in (APX21210.bgl). Then you will have to recheck FS displays. Be aware a backup of the original file is done by the program in case things go wrong.. 

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Thanks for bringing in your experience Hervé.

 

I had looked at three different sources of information all listing different runway headings and differing magdev depicted on the charts :(

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You're correct Stephen. It's a little bit conflicting..Latest Jepp airport chart (5-Jul-2013) and AirNav information still indicates a 8°E magnetic variation (1980) and a 124° mag runway heading (that is in line with original FSX data but not with the actual 2010-2013 magnetic variation and ILS data, see below). If you installed the updated magvar.bgl file you will read a 127° mag heading on your HSI while aligned on 12R..The situation will be different on other airports that updated their magvar data more recently..This is a limitation of such "global" changes but magvar.bgl update only affects the heading you will read on your instruments NOT the drawing of some magnetic axes by FS and/or the NGX FMC

 

Now, interestingly, the ILS chart (Jepp 30-Mar-2012 & FAA) indicates a 127° mag course! Could be that the airport chart was not updated adequately regarding the magnetic variation as far as there is no indication it is an "offset" ILS (in FSX it is perfectly aligned on Rwy).

Regarding NGX FMC data (WpNavAPT.txt) , I cannot analyze things further on as far as I don't own them. However latest PMDG AIRAC for FS9 (I have) gives the following (should be the same in FSX)

SAN ANTONIO INTL        KSAT12R08502126 29.542747 -98.485542110.9012700809

indicating a 126° heading for the rwy and 127° for the ILS. Probably these values are only used for displaying FMC axes but it may help interpreting what you see

So, things are multifactorial and I'm afraid I cannot go further ;-) but the discrepancies you observe are indeed in line with the differences I mentioned above. You may wish to make some corrections for testing

 

Hervé 

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That's really, really helpful Herve, thanks. I figured something else was affecting those courses when the Map view kept showing different numbers. 

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Awesome thread guys, thank you, never learnt so much about the mag/hdg stuff before :)


23.png

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