An ecclectic mix of airports, applications, utilities and other freeware "stuff" for MS Flight Simulator
AI Flight Planner
A fully-integrated, TTools-format compatible AI flight planning tool for Microsoft Flight Simulator, both FS9 and FSX versions, - from stock and add-on airport data collection through flight plan preparation and editing to traffic .bgl compilation/de-compilation. Includes a complete flight plan subsetting capability as well as FS9 to FSX file conversion.

AI Flight Planner

Please Be Aware . . .

Don't Mix FS9 and FSX Traffic Files: FS9 traffic files are compatible with FSX. However, as described more fully in the User Manual, if FSX "sees" a compiled-for-FS9 traffic file, it will generate AI traffic for that file and any other compiled-for-FS9 traffic files it "sees"; but, it will not generate traffic for any compiled-for-FSX files. This has nothing to do with AI Flight Planner. It is a FSX "feature".

So, if you don't get (or suddenly stop getting) AI traffic from compiled-for-FSX traffic files, the first thing to look for is a compiled-for FS9 file somewhere within FSX's scope - probably in the Scenery\World\Scenery folder. You'll find AI Flight Planner's Find FS9 Files function very useful for this.

MAIW and WoAI Always Install FS9 Traffic Files: At time of writing, Military AI Works (MAIW) and World of AI (WoAI) packages include FS9 traffic files only. Even though labelled and/or installed for FSX, you still get a FS9 traffic file.

Consequently, if you are running FSX and have any FSX traffic files, your first step after installing a MAIW or WoAI package should be to convert the newly-installed traffic file (usually located in the FSX\Scenery\World\sceneryfolder) to FSX format using AI Flight Planner's "Files / Convert FS9 Traffic Files to FSX" menu item. (Please note, an updated installation guide for MAIW packages, including directions for converting them for FSX operation, is available at The Owl's Nest).

Traffic Files Don't Have to be Saved in the FSX\Scenery\World\Scenery Folder: Many add-on flight plan packages recommend placing (or automatically place) their traffic files in the Scenery\World\Scenery folder along with the default traffic files. This is not necessary and can be problematic.

Traffic files may be placed in any \scenery sub-folder that FS9 or FSX can "see" - such as those inAddon Scenery. Placing your traffic files in one or more separate folders helps avoid mixing FS9 and FSX traffic files and can make diagnosis easier when mixing is suspected. Do youself a favor and move all those add-on traffic files out of Scenery\World\Scenery folder and put them in the \scenery subfolder of one or more folders enabled/disabled from the Scenery Library. That way, you can easily turn that traffic on and off and isolate it when necessary. (Some "purists" will tell you that placing your traffic files anywhere other than Scenery\World\scenery is a bad idea. And, they'll back that up with technical reasons. But, I have never experienced any difficulty from so doing.)

The "37 Minute" Problem: AI Flight Planner and TTools both permit specification of arrival time for a flight plan leg. (TTools used the "@" symbol to designate a user-specified arrival time. AI Flight Planner does not use the "@" symbol; any arrival time more than two minutes different from the system-calculated ETA is assumed to be user-specified.)

Unfortunately, the AI/ATC "engine" does not "understand" user-specified arrival times. Except during take-off and landing, AI aircraft fly at the cruise speed specified in the aircraft text file. Thus, they arrive at the destination at a time governed by the leg distance divided by cruise speed which, especially for scheduled airline operations, is usually somewhat earlier than specified. If the time differential is more than about 37 minutes, the aircraft won't materialize for landing. Rather, you won't see it until it "spawns" in a parking spot at the destination airport in preparation for departure for the next leg.

This situation led some suppliers of TTools-compatible AI flight planning information, including WoAI, MAIW and, until recently, AIG, to specify artifically low cruise speeds for commercial jet aircraft - often 200 kts. While this reduced cruise speed avoided the 37 minute problem, when used with AI Flight Planner, it leads to other difficulties. So, prior to using prepared flight plan data with AI Flight Planner, you should ensure the cruise speeds are realistic. If they aren't, AI Flight Planner provides several alternatives for restoring cruise speeds to their normal values.

For a fuller explanation of the "37-minute problem", please refer to Section 4 of the User Manual.

Day-of-Week Encoding: In FS9, the day-of-week encoding scheme for weekly flight plans uses 0 for Sunday, 1 for Monday and so on to 6 for Saturday. For FSX, Microsoft changed the day-encoding to 0 for Monday and 6 for Sunday.

AI Flight Planner always displays day-of-week information based on the FS9 day-encoding scheme, letting the compiler handle the different schemes required in the traffic files.

Compilers: There are several different AI flight plan compilers in widespread use:

  • TTools, a compiler/decompiler for FS9 and earlier versions of MSFS
  • AIFPC, a TTools-compatible compiler/decompiler for FS9 and FSX (early versions of AI Flight Planner used the AIFPC compiler/decompiler)
  • Traffic DataBase Builder (TDBB), Microsoft's AI traffic generation utility for FS9 and FSX, available in the SDK
and AI Flight Planner.

TDBB is not TTools compatible; its source data formats are very different from those used by the others.

There is a common misconception that flight plans for FS9 must be in TTools format and those for FSX must be developed using TDBB. And, often, you will hear "FS9 flight plans can't be used with FSX". But, the reality is, FS9 traffic files compiled with TTools are compatible with FSX (but don't mix them with your FSX-format traffic files). And TDBB, to the surprise of many, was available in (and generates traffic file compatible with) FS9 as well as FSX.

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We welcome your questions, comments and suggestions regarding this website and the "stuff" available from it. Please feel free to contact us. In particular, please report any problems you experience with the add-ons, applications and utilities.