ILS 06 at KELM I-UEK

Navigation Data ILS
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In the latest 2014 Rev 3 data, the localizer course is shown as 61 degrees. Should be 62 degrees (62.39 to be precise) It causes the aircraft to track at an angle to the runway until quite close to the DA currently.

FAA Data record:
https://enasr.faa.gov/eNASR/nasr/Current/ILS/31749

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Thanks James - yes, this will be fixed with the next upcoming revision. We calculate these values now by our own (center and offset) to get a more precise value and we have figured out that we have used a wrong reference on some airports. Sorry - the new value in this case will be 50.28581103 (true bearing).

Thanks again,
Cheers,
Richard

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Thanks for checking Richard!

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Revision 4 is out now - the wrong reference to calculate the ILS course should be fixed now.
Cheers,
Richard

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@JRBarrett one point to this - I have identified that the localizer position for RWY 06 is slightly off. We are currently checking this with Jeppesen - this happens in 2014 and in the new upcoming AIRAC 2101 also. Only just as information …

Thank you :wink:
Richard

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I loaded 2014 Rev 4, and after rescanning the scenery DB with LNM, it does appear that it is now very slightly misaligned to the left of the centerline. With Rev 3, it was more significantly skewed to the right of the centerline. I think the actual true heading of the runway is almost exactly 50 degrees or 62 magnetic. The ILS 24 on the other end is perfectly centered at 242 degrees.

Of course, when I hand fly an ILS, I’m lucky if I arrive at the runway at all😁

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@JRBarrett The position of the localizer seems to be off, as @NAVDataOld already said. And it was already off at the same position in Rev 3. In Rev 3 it was angled as to lead to the runway-threshold and with Rev 4 its parallel to the runway.
KELM

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Yes, I see the same thing when I zoom in close in LNM. I assume the localizer coordinates are in the base airport APX file, and not something Navigraph can override. If so, I’ll have to report it to Zendesk. I work at the airport and can confirm that the actual localizer antenna is beyond the threshold of runway 24, not beside it as shown.

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Hi James,
no, we don’t use any underlying data - so the loc positions come from our data. We have asked Jeppesen yesterday about this issue and indeed, they confirm the misplaced loc antenna. They have now started a normal internal process to change it - so you should expect the correct loc antenna with the next cycle 2102 (AIRAC 2101 is still ready and therefore you still have the wrong coordinates).

Cheers,
Richard

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Thanks for checking with Jeppesen!

I uninstalled Navigraph, and refreshed the scenery library in LNM based only on default data, and the ILS 06 localizer originates from the proper location. Reloaded navigraph, refreshed the LNM scenery library again, and it shows the ILS originating on the left side of the runway as in the above screenshot.

I looked at the 0x0013 record for this ILS in the default NAX file in /fs-base-nav/0302/27170.bgl, and compared the DWORD values for the localizer Longitude and Latitude to the Navigraph version of this same file, and they are exactly the same The only difference I see is that the default NAX file has the localizer variation set to the 2020 value of 11.5 W, while the Navigraph file has the FAA published variation of 12.0 W, but I wouldn’t think that would produce a position shift of the localizer origination point in the scenery.

Of course, as we know, when the default nav data is the only source, and when flying a default aircraft in the sim, something in the APX file forces the localizer to the runway heading no matter what the NAV file contains, so perhaps LNM is being affected the same way?

According to the FAA 5010 document for KELM, the ILS 6 localizer antenna is at N42 10 6.283 and
W076 52 45.51

I don’t know how to convert the DWORD values in the BGL back into the corresponding decimal lat/lon, but looking at the Navigraph data for another add-on that has the localizer data in standard text format, I see that the IUEK latitude is the same as the FAA value, but the Jeppesen longitude is slightly different than the FAA’s.

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Right, but in this case the position is really wrong in the data and also in this case the sim uses really our data and not any other data.

No sorry, thats not correct … you can check this with LNM also. Change in the “Scenery Library” the “MSFS2020” to “Navigraph … cycle” and you will see exactly the same wrong position. A second example, when you look into the PMDG dataset in the wpNavAID.txt file, you find following entry:

IUEK IUEK ILS 42.168411 -76.880194109.10T

image
The red marker is the wrong position with the current coordinates above, the blue one the correct one from the FAA.

So, this is really a data issue, which should be fixed with the AIRAC 2102 :wink:
… and by the way, you have really a “golden hand” for that - to report a slightly wrong course which results in a wrong loc-antenna position :slight_smile: … good stuff :slight_smile:

Cheers,
Richard

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I probably would never have noticed ordinarily, but this is my r/w home airport, and I am working on a project in the scenery editor to fix the incorrect default taxiway names, and checking the updates in LNM - that’s where I noticed the ILS course wasn’t quite right for runway 6. Thanks for looking into the problem with Jeppesen!

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