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FSXA ICAO codes being changed automatically

raymk

raymk

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I use a mixture of AIFP and Traffic X AI schedules. The Traffic X ones supply me with the 'bulk/background' AI aircraft wherever I choose to fly, with my AIFP ones giving me specific aircraft that I want to 'see' at any particular locations.

I happened to look at one of the Traffic X AI BGL files which contained a load of VFR flights in the USA. On loading this BGL into AIFP, I get an onscreen message stating that 3 airports had been 'replaced' by alternative ones.
Examples of Traffic X flights -
F37 to KSRR (21nM) changed to KCHN to KSRR (1271nM)
H70 to 05V (180nM) changed to H70 to 02MU (564nM) and
S37 to 00M (796nM) changed to S37 to SXX (1769nM).

i.e. F37 replaced by KCHN, H70 replaced by 02MU and S37 replaced by SXX.

So it was clear that this was not a case of airfield ICAO changes in ident. as the flight distances were completely different.
Further investigation revealed that, in FSX, the airfields F37, H70 and S37 are valid airfields with available parking and therefore do not need to be replaced by any alternatives.
Looking at the AIFP file structure, I see that, in the "Base Data" folder there are various files that look as if they are playing a part in these automatic changes. (FS9-FSX_Chg_AIFP.txt and ICAO_Changes_FS9-FSX.txt)
Can I edit any of these files to eliminate these automatic 'changes'?

If I look at these 3 ICAOs in the Airport Editor and look at the 'Airport in' line, there is a 'Cross' under FS9 and FSX and P3Dv5. These ICAOs do exist in FSX.
What should be done to correct this situation?
 
Hi Ray. Alternate ICAOs have nothing to do with the change in the complement of airports from one version of Flightsim to another. Rather, they are result of a user specifying that AI destined for particular ICAO(s) should be rerouted to a different ICAO. This feature is most commonly used where an airport is closed and replaced by another nearby having a different ICAO code. But it is not so restricted. It is a completely manual operation.

All alternate ICAO specifications are held in the AIFP file ICAO_Alt.dat. Please check that such a file exists on your system and that it calls for the re-routing you are experiencing. If so and you no longer wish to have such re-routing, simply delete that file - or edit it to eliminate the ones you no longer want. (You can accomplish the same thing for individual airports via the Airport Editor.)

As for the "X"s, I believe AIFP marks airports for which an alternate ICAO has been specified as being non-existent to avoid further inadvertent specification of those airports as valid destinations.

The reason you are just seeing this now is that ICAO_Alt.dat was inadvertently ignored in recent releases. Please also note you can turn off automatic re-routing by unchecking the "Use4 alternate ICAOs" item in the airports menu.
 
Don, thanks for the reply - I do not have a file "ICAO_alt.dat" and my "Use Alternate ICAOs" is not selected. This suggests to me that AIFP must be using the files I mentioned before. The 3 airports I listed are contained in both of those files as (I presume) alternates?

AIFP in use is 3.3.1.9 - I am waiting to update to a 3.4 version but I will have another question before I do that.

[Edit} Have just found another file "StockAirportList_FSX.dat" which lists F37 as a valid FSX airport so why should AIFP not want to use it?
 
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I'm mystified. ICAO_Alt.dat is the beginning (and end) of every alternate ICAO transaction and it's not clear what AIFP is even looking at alternate ICAOs if that file doesn't exist. But, I just noticed you are using 3.3.1.9. Perhaps the answer lies therein.

The whole arena of airport processing changed between 3.2 and 3.3 - the purpose of which was to handle PV5 airports in a transparent manner. 3.3,which was updated to 3.4, added the handling of FS2020 airports. It should not have created any difficulties with pre-PV5 airports and the sole issue that was reported (alternate ICAOs not working - which seems to be the opposite of your issue) was fixed last week in General Release 3.4.1.5.

3.3.1.9 appears to have been a development release that went through 5 more iterations before being released generally as 3.3.2.0. I no longer even have the source code for it.
Even if I took the time to try and figure this out in 3.3.1.9, I wouldn't be able to issue an update. What is stopping you from updating to 3.4?

EDIT: Incidentally, you've had 3.3.1.9 since last August but, presumably not this problem until recently. What's changed recently?
 
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This is the first time I have looked at this particular Traffic X AI BGL using AIFP.

I have now looked at my "AirportsList.dat" file and found the entry for airport F37 - it is follows (with previous and next entry) -

United States|New Mexico|Carlsbad|Seven Rivers|32.5987248122692|-104.426350146532|1024.128M|62NM||||0202\scenery\APX20200.bgl|||*|
United States|New Mexico|Carrizozo|Carrizozo Mun|33.6488612741232|-105.895686149597|1637.08M|F37||||0202\scenery\APX19200.bgl||Q37|KCHN|KCHN
United States|New Mexico|Chama|Chama Land & Cattle Co.|36.8666792660952|-106.567257195711|2446.02M|NM16||||0202\scenery\APX19180.bgl|||*|
and, for interest, the entry for the 'replacement' airfield KCHN -
United States|Florida|Wauchula|Wauchula Mun|27.5136497989297|-81.8806390464306|32.918M|KCHN||||0302\scenery\APX26220.bgl||F37|*|

This leads me to wonder why the entries for F37 and KCHN have the fields near the end listing what appear to be the 'replacement' airfields that AIFP is using in my case. How do these entries get added to the "AirportsList.dat" file? There must be a function during the "Collect Airports" operation that, having found an airport ICAO, it 'looks up' in another file to see if there is an alternative which it then adds to the end of the line.
I note that the entry for 62NM has empty fields after the "APX20200.bgl" field whereas the entries for F37 and KCHN have entries in the same fields. Note the multiple entries Q37|KCHN|KCHN at the end of the "F37" line?
What is the structure/format of these data lines?

I might 'play around' with these entries to see what effect I can get with respect to what I am getting during my procedure.

Updating to 3.4 -

When I run my AIFP 3.3.1.9 I expect to be advised that a later version exists and be asked if I want to download and update my version. This is not happening even though I have the appropriate options ticked. I also still have a version 3.3.1.2 on my system - if I run that, I do get the message about updates available, etc. I assume that there should be an entry in AIFP.ini that controls whether this should happen or not but I cannot find any difference in the AIFP.ini files for both versions. I will attach my 3.3.1.9 AIFP.ini file for your inspection. I would like to get this sorted out before I make the upgrade.

[Edit]
Attached - image of Airport Editor for F37 which tells me that F37 does not exist in FSX which it certainly does - how can this be changed to reflect this? AIFP-1.jpg
 

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Don,
I have done some serious thinking and decided to create a brand new installation of AIFP 3415 (not updating my current version) to see what happens.

I will run some tests to see if the same effects occur.

Two quick results.
Opening F37 in Airport editor - shows as 'existing' in all versions.
Opening a Traffic X AI flightplan BGL that uses F37 results in NO replacements

This suggests that my "AirportsList.dat" file has got in a mess somehow. All I need to do now is use "Collect Airports" to update "Airportslist.dat" to pick up my extra and revised airports and then see if all is still OK.
 
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When I run my AIFP 3.3.1.9 I expect to be advised that a later version exists and be asked if I want to download and update my version. This is not happening even though I have the appropriate options ticked.
Click to expand...
As was reported several times in the forum, this feature was not working for a while. However, each new significant release was announce individually.

I have done some serious thinking and decided to create a brand new installation of AIFP 3415 (not updating my current version) to see what happens.
Click to expand...
That seems like a very good idea.

This suggests that my "AirportsList.dat" file has got in a mess somehow.
Click to expand...
Almost certainly the case. With both PV5 and FS20202 being introduced in the past 6 months, the large number of changes prevented any AIFP release from becoming stable. I think you'll find 3.4.1.5 much more to your liking.
 
Don,
apologies for troubllng you earlier.
My NEW install of 3415 seems to be working as I would hope having copied my 'Flightplans' data over and set the 'Options' to as I had in 3319.
Have run "Find/Collect Airports" which seems to have up-dated my "AirportList.dat" to a state where, after some inspection, I can see that entries exist for where I have created modified airfields and also some airports that did not exist in FSX. I note that there are a few strange entries that refer to FS2020 but I will get on with using this version until something unexpected happens.
It is strange about what happened to my previous "AirportList.dat" - I guess that messing around with "Find/Collect Airports" in the past must have picked up some odd bits of data which did not cause any problems until I tried to do something that I don't usually attempt.
 
As I mentioned in an earlier post, the processing of airports was completely redeveloped between 3.2.and 3.3. to accommodate the thousands of differences between the airport complements in FSX/P3D(until v4) and PV5. Then, I'd no sooner launched 3.3 than FS2020 came along with yet another complement of airports. Fortunately, the approach I had taken to accommodate PV5 was easily extended to FS2020.

The one common thread throughout this redevelopment, however, was "ICAO_Alt.dat" to hold the alternate ICAO pairings. It's been around for as long as I can remember. You reported not having that file, but you still had airports being replaced. This likely was the result of a faulty automatic update of your AirportsLIst.dat when you first installed 3.3. (While I no longer have the source code for that release, I recall that AirportsList.dat was only regenerated when airport data changed. Otherwise, the file was used from one session to the next, thus propogating any issues. AIFP now generates AirportsList.data on each startup.)

All that being said, at some point in the life of your system you must have had a IACO_Alt.dat containing those relationships.

Glad to hear you have recovered.
 
Sorry Don, should I now have an "ICAO_Alt.dat" - if so, it did not come in the download of 3415 and it was not created when 1st run?
 
ICAO_Alt.dat holds any alternate ICAOs you program. If you haven't programmed any (either using the Airport Editor or via AIG updates), then the file will not exist.

It will be created automatically when you do program an alternate ICAO.
 
That's fine then - I haven't dabbled with creating alternate ICAO's. Will get on with using the new AIFP and see how it goes. Thanks as always. 😌
 
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