Default FS2004 GPS Airport Data Location

I used ADE9X version 1.70 (w/ Prokey) to modify the default FS2004 KSAN airport to bring the approaches up to current AIRAC data. The first thing I did was to edit the ARP to reflect the current magnetic deviation to -11.5 (11.5 degrees east). The current chart valid until 04 JAN 18 shows a deviation of 11.8 degrees east as of JAN 2015 with an annual rate of change of 0.1 west.

The stock navaids have reflected that change. I-UBR shows a heading of 286.5 True and thus 275 degrees magnetic. I-SAN shows 106.5 True and thus 95 degrees magnetic (I also gave it the correct frequency of 111.55).

I then went to Approach mode and redid the approaches using the current AIRAC charts for guidance (adding terminal waypoints when necessary). All is good at this point and I am happy with the result.

However, when you bring up the airport information in the default FS2004 GPS (or the map view) the "data" for the two navaids still shows the default (FS2004 out of the box) headings of 093/273. I assumed this was because the GPS does not get it's "airport data" from the modified ADE airport because it is a "stock" navaid. Then I noticed the new frequency of 111.55 is listed, so the GPS is reading the changes I made, yet why does it still show 93/273 and not 95/275 for the navaid headings?



Resource contributor
Changing the magnetic deviation in an ADE file does not change the actual deviation, only the headings at that airport. Thus you end up with the incorrect headings. Only editing the magdec.bgl file will change the acutal deviations. I don't know how to do that.
That makes sense, Tom. Thanks for the response.

I guess by using herve's magdec/database update that could be accomplished, but I have chosen not to use it because it "kills" the default FS2004 flight planner and I use that to plot my star shot points when I use the bubble sextant available from AVSIM (yes, celestial navigation in both FS2004 and FSX is possible).

Do google it find "madgec" get download file magdec.bgl make a new folder in the FS2004\ ADDON SCENERY\ then type new folder (MAGDEC) then another new folder (SCENERY) install magdec.bgl that's all you need this. You're done. All heading is correct perfectly! I was very frustrated for 2 months could not figure it out someone found my comment post somewhere I think Flightsim forum. He told me to do this installed. I finally fixed.

Hey Stuart,

I have done that already and have that magdec.bgl file installed, but even that data is out of date. The magnetic variation at almost every airport in the world is constantly changing because the magnetic North Pole is constantly moving. Even with that file active the GPS still says 273/093 and I have the magnetic variation for KSAN set "perfectly" at 11.15 degrees east up to date to January 2018 data. I wish I knew how to open that file and make changes to the data therein... Tried bgl2xml, but that did not work. Seems that's only for object bgls.

Come to think of it, though. I have magdec.bgl in the number one priority in addon scenery so it is probably overriding the KSAN ADE data. I wonder...if I move it to a lower priority than the KSAN ADE Airport what the GPS will say?


EDIT: Nope, completely disabled the magdec.bgl file and the ils info for KSAN still said 273/093
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Resource contributor
That's amusing that you are using a bubble sextant and want the latest magdec data. I assume it was very different when the sextant was in actual use. :)
Well Tom, it's your fault in a way. The Connie from CalClassics came with the BBsextant by Dave Bitzer and Mark Beaumont and I just had to learn how to use it. Besides, I like to fly my T7, B747, and B737 once in a while as well. ;)

Also, I figured out how to fix the heading issue and the answer was right in front of me all along. :oops:

Changing the ARP magnetic variation, as you pointed out, did nothing for the ILS headings, although I assumed it would. Turns out, after looking at KSAN in raw data view since I have prokey, I suddenly realized that the ILS's IUBR and ISAN also have a magvar value and it was still set at -13.229875 degrees. Once I changed that value to -11.15 the headings now show 275/095 on both the default GPS and the airport map view data.

Problem solved.