MSFS2020 Problem with ILS "The localizer is not correct"

[AbdeDzd]

Hi,

I’m using Navigraph’s FMS Data, and is on AIRAC 2504

I am having a problem at Adrar Airport DAUA
It seems this airport’s ILS localizer location is wrong, It’s causing MSFS planes to just follow the ILS to the side of the runway.

The planes I have tested:
Fenix Airbus A320
Asobo Cessna 152
Microsoft Airbus A310-300
FlyByWire Airbus A320-neo

[AbdeDzd]

Hi,

I’m using Navigraph’s FMS Data, and is on AIRAC 2504

I am having a problem at Adrar Airport DAUA
It seems this airport’s ILS localizer location is wrong, It’s causing MSFS planes to just follow the ILS to the side of the runway.

The planes I have tested:
Fenix Airbus A320
Asobo Cessna 152
Microsoft Airbus A310-300
FlyByWire Airbus A320-neo

Screenshot 2025-09-21 2349301462×1034 77.6 KB

[AbdeDzd]

there is a problem with ILS. It is not related to the airport design, of course.
It seems that the problem is related to Navigraph-Navdata.
Aircraft that do not use Navigraph do not encounter this problem.

[AbdeDzd]

It seems that the problem is related to Navigraph-Navdata.
Aircraft that do not use Navigraph do not encounter this problem.

[NAVData]

Hi,
It seems it´s slightly offset from the AIP or from the MSFS.

Here, directly from the AIP:

So, when you convert the coordinates in decimal degrees, it´s:
27.84989444, -0.175041666

When you now enter the coordinates in ex. Google, you will see the slightly offset to the right:

In addition to this, it seems that the MSFS runway is based on the satellite image and not the real-world coordinates, because when you compare the real-world coordinates with the MSFS values or also the satellite image, you will also see a shift of the centerline:

Here the AIP data:

… and here, you see the THR point of 04:

… and here the delta between the stock MSFS threshold point 04 (red marker) and the real-world threshold point 04 from the official AIP (blue marker):

The data provider always uses the AIP values from the countries, so we must trust it. This may be the reason why this is only a CAT I approach.

It looks like a combination of wrong runway coordinates and offset loc coordinates. With our data installed, you see the real-world data and, therefore, the little offset.

I hope that helps,
Richard

[AbdeDzd]

So there is a discrepancy between the actual LOC status and the simulations.
Now, what is the solution to fix this problem?

[NAVData]

@AbdeDzd

Now, what is the solution to fix this problem?

There is no solution, at least for our data, because as I have shown you, the navdata are correct according to the AIP.

It is also possible that the AIP is not 100% accurate, but I don’t know it. It is likely a combination of MSFS stock scenery and AIP data, which results in this slight offset.

It is a CAT I approach, so I recommend flying the short final manually. The offset is only a few feet to the right of the centerline.

I hope that helps
Richard

[AbdeDzd]

Thank you for your help.

I have now deleted the navigraph-navdata-base and navigraph-navdata folders from Community.
Aircraft that do not use Navigraph Like Airbus A310-300; inibuilds A300-600; Cessna 152. do not encounter this problem.
It seems that the problem is related to Navigraph-Navdata Like PMDG Fenix Airbus A320

[AbdeDzd]

Actually, I designed the airport and posted it on flightsim.to.

https://flightsim.to/file/96649/airport-adrar-daua

Some of the airport downloads had this problem.

[NAVData]

Hi again,
I’m unsure if you have fully understood my analysis.

Our data provider is Boeing/Jeppesen, which is the biggest data provider worldwide. Any data provider gets the data from the AIPs of each country.

You can’t expect the same quality or accuracy from all countries. Some are good, some not, but the data provider must trust the data. Of course, all providers validate this data in a basic way and try to make adjustments if necessary. Here, it seems that the delta for an adjustment is too small, and therefore, you can see the data that the AIP Algeria offers.

So, I would report this to the country first to determine if the location of the antenna is correct. It is not a navdata issue, it is a country issue, and I assume (when you really read my posting) that I have shown you in very detail what the problem is.

Thank you very much
Richard