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Duplicate aircraft when compiled

Hello all. Hopefully, a reasonably easy question... I have converted FS9 flightplans to FSX standard and also created my own flightplans using AIFP using the correct FSX settings etc. When I've compiled them using 'Compile Traffic.bgl', I noticed that ALL of the aircraft were duplicated when I eventually loaded up FSX. After spending some time looking at other peoples threads, and noting the problems caused by the '37 minute rule', I tried compiling a very basic two leg flightplan of my own using 'Compile Raw' in the hope that it would rid the second (and sometimes third) aircraft that were showing up. It didn't work. My flightplans validate without error, and I have no other 'traffic' files/programs installed. The flightplans all appear to be constructed correctly.
One problem I believe it may be, is the fact that I've converted some WoAI flightplans from FS9 format to FSX using AIFP. I've noticed that if I remove all of the WoAI flightplans from the scenery file and rebuild the library, all duplicated aircraft disappear. I have gone through the WoAI plans and cannot find a reason for the 'duplication' at all.
The question being... Is there any known way to eliminate the duplicate aircraft from showing up at all?
(I am using FSX SP2 on Windows XP SP3)
Thanks in advance for your help & regards.

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Resource contributor
By "duplicate aircraft", I assume you mean that two or more instances of your flight plans are being flown simultaneously.

Just to eliminate the easy stuff first, I assume you're aware that if you interrupt FSX to, say, adjust the Scenery Library, all the AI in the system at the time of the interruption will be duplicated when you resume.

I don't use WOAI flight plans directly. However, I suspect if you used the WOAI installer at some point, the traffic files were placed in the \Scenery\World\Scenery folder. Perhaps this is the source of your "duplicate aircraft". If so, just delete/disable the old files in that folder.

Thanks for the reply. I've been playing around with FSX since I placed the original post. AIFP works perfectly (superb program! Thank you). For some reason, WoAI flight plans won't convert properly. . That is the one and only problem that I have found. Essentially, they are shown to be FSX compatible, but appear to have been made in the FS9 format. I have gone through the process of converting them to FSX and then tried to compile them in both 'normal' & 'raw' modes, but am still left with duplicate aircraft when FSX is loaded from scratch.
I've de-compiled the converted FPs back into AIFP to view them, and they all seem fine
I have since deleted all of those flightplans and will simply have to resort to building my own, until there are more 'made for FSX' ones available.
Kind regards.


Resource contributor
Essentially, they are shown to be FSX compatible, but appear to have been made in the FS9 format.
Dunk, what do you mean by "made in the FS9 format"? At the source level, there is no difference in format between flight plans intended for use with FS9 and those for FSX. In weekly flight plans, the day encoding may differ by one day, but that can be handled by the compiler. In both my AI packages (CYYJ Custom AI and BC Regional AI), I have one set of source files that are used to generate traffic files for both FS9 and FSX.

Are you sure your WoAI flight plans need conversion. If the package is less than about 18 months old, the traffic files will already be in FSX format. (If they weren't, it's unlikely you'd see any other FSX AI.)

If you delete all your new traffic files and the AI still appears, then there's another traffic file for that AI on your system. I have now confirmed that the WoAI installer places the compiled traffic files in the FSX \Scenery\World\scenery folder under the name "traffic_xxx_WoA_airline.bgl". If you want to get rid of the WoAI-installed traffic files and use your own, simply delete the WoAI files from that FSX folder.

Incidentally, please note that the aircraft files for WoAI flight plans set the aircraft cruise speed to around 200 kts (to address the "37 minute" problem). If you compile with AIFP's "normal" mode, this speed will be halved. If you're not familiar with this situation and how to handle it, please see . I am currently developing a new feature for AIFP that will restore the original cruise speeds for all aircraft.

Hello Don. Forgive my lack of clarity, it's been a long day at work... When I went through my AI files on my PC and, I realised that no FSX specific (i.e the default AI)traffic was showing up. After reading the other posts, I figured that this was because there were some FS9 traffic files in my scenery folder. I therefore had a look at the WoAI files that I'd installed, decompiled the BGL files with AIFP, and they were shown to have been originally made for FS9. I then duly converted them, using AIFP, to FSX format using the 'normal compile' method.
When FSX was reloaded, there were two aircraft for each one that was listed in the WoAI flightplans (for example, two aircraft with a registration of G-AIFP, same aircraft, both being at the same airport at the same time etc). I therefore brought that flightplan back into AIFP by decompiling it, and then recompiling in 'raw'. When FSX was rebooted fresh again, it still showed two/duplicate aircraft as before.
I have deleted all of those flightplans, and everything is fine now (bar several hundred less aircraft in the skies). I haven't had the time to 'play around' with the plans yet due to work commitments. Hopefully, over the next few days, I'll have time to sit down at my PC and have a real good look (mainly to ensure that I'm not doing something daft!).
Thanks for taking the time to respond. It is appreciated.

Hello. Once again, thanks for all of your assistance. I've now got AIFP thoroughly sussed. It works a treat! As for the duplicate aircraft, you were entirely correct. It was simply because I was not restarting FSX each time, to 'accept' correctly the new BGL files. Another issue that I had created myself with regards to the WoAI flightplans, was the fact that when I 'converted' them to FSX, as such, I had 'ticked the box' in AIFP that asks whether or not I wish to add "FSX" at the end of the saved title. By doing this, I was basically generating a second BGL whilst leaving the original FS9 bgl in situ without deleting it because I had not overwritten it. AIFP is a grand program, well done & thanks for making it freeware. Kind regards. Dunk.