I am working on a global AI package using planes of the 1930s. All flightplans are set VFR which was pretty much the mode of flying for most of that decade. My problem is that the aircraft often switch from VFR to IFR irrespective of how the flights are set by me. At first I thought that it was happening when visibilty was low or the weather was rough but after watching the AI closely I can see nothing obvious causing them to suddenly switch from VFR to IFR. The flightplans were created using the MS SDK. I have decompiled the flightplans to check and all flights show as VFR, weird. Any thoughts?Andrew BrownROARING THIRTIEShttp://www.gordiusfs.pwp.blueyonder.co.uk/

Hi,- "The flightplans were created using the MS SDK."Why dont you use Traffic Tools (TTOOLS)(freeware) ?Greetz. Jos

"My problem is that the aircraft often switch from VFR to IFR irrespective of how the flights are set by me."I can't speak for how M$ does AI, but I can tell you that when you use TT to compile a traffic file, they will go IFR automatically as weather conditions dictate. Try downloading TT and read the help files...very helpful.Hope this helps,MikeI'm confused. Wait...maybe I'm not!www.flightontario.com

Thanks for the replies. I am familiar and do normally use TTools although it's been a while since I read the documentation I must confess. A quick explanation is needed I think. The idea behind the project is for a global 1930s AI so I used the MS thing to build a base pack. It "fills" the skies with largely private aircraft such as the Tiger Moth. I used the MS tool to build a lot of flightplans at one bash using a batch file resulting in a traffic BGL with a very large number of flightplans very easily. The next step was to decompile using TTools for a quick look at the large file it had built and to check that all were VFR which they are (changing the N reg to the correct letter(s) should be fun :-) ). I am very slowly looking for data to use when building flightplans for the airlines of the time which I am compiling using TTools (so far only Imperial Airways but have to start somewhere).Thanks for the info regarding the way FS9 converts the plans to IFR "as weather conditions dictate". A bit of a shame as far as what I am doing goes, in a way it might have been better to see the aircraft grounded. Then again maybe not :-) Either way I am enjoying the work and for me at least its nice to say goodbye to the Airbus, Boeings, etc taxiing behind my poor little biplane (scary) and now to be followed by a JU52 instead.Andrew BrownROARING THIRTIEShttp://www.gordiusfs.pwp.blueyonder.co.uk/

Hi,It is also a while I made flightplans voor AI traffic.But I remember now that I set all my flightplans to IFR, even if I let fly a Cessna on 3000 feet. It was recommended to do so. (Why I don't remember).Maybe you try to do so and see what happens. I had no problem at all, for low flight or for flight at high altitude.Greetz. Jos

Thanks I will have a try sometimeDon't know if you spotted it but I have uploaded the first 1920s/1930s AI package to AVSIM. rtbasepack.zip. Feedback would be welcomed!Andrew Brownhttp://www.gordiusfs.pwp.blueyonder.co.uk/