IdealFlight help

Initial Screen


Ideal Flight does many things automatically to help set up a fully prepared flight with advanced plan and flight briefing, as well as quick FSX launch, flight monitoring, scoring, and record keeping. A unique weather engine featuring a simulation of the Earth's weather is included, for interruption free offline play.

Ideal Flight helps you find the airports with the runways and parking you need. Ideal Flight creates flights based on your pre-selected criteria. Do more flying, see more airports.

See what else you get with Ideal Flight. Please have a look at the Walkthrough and Feature List.

Drag and Drop Background Images

Drag and drop .bmp images onto Ideal Flight and the backgrounds of the pages will change to the images you dropped. Recover the original image with the popup menu.


Help is available throughout Ideal Flight. For help to appear press "F1".

Pop-Up Menu

A Pop-Up Menu is available throughout Ideal Flight. Right-Click or press Escape, for the pop-up menu to appear.

Check IF Version

This function checks with for a more recent version of IF.

Maintain Indexes

When Ideal Flight is run for the first time, a set of index files are built. If add-on airports are installed or removed, Ideal Flight will prompt for an index rebuild.

Make sure add-on scenery has been successfully installed and tested on FSX before running Ideal Flight and starting an index rebuild. Ideal Flight can detect most add-on changes, and will recommend the indexes be rebuilt. If an add-on airport has altered, rather than been installed or removed, then the index re-build may have to be started from the popup menu, before going on to the Airport screen.

Aircraft Folders: Edit the list of folders that contain User and Ai aircraft. See fsx.cfg [Main] section, example: "SimObjectPaths.6=C:\AIPlanes". Note: Not used for Steam DLC.

Aircraft Index: Only refreshes data values if files have changed since the last index.

Create Aircraft Index: Re-creates all Aircraft Flight Parameters (Range, Cruise Speed, etc.) for all aircraft. Aircraft.ini files are copied to Aircraft.ini.old just before recreating the files.

If changes are made to the scenery and IF indexing is cancelled, the scenery changes are ignored until IF10 scenery index maintenance is carried out manually.

ForceMerge.txt: Include the ICAOs of any addon airports missing ILS information. Some addon airports (very few) have opted to use stock scenery data for ILS but forgot to include the proper record in the data. Please see Errors and Problems

Info.txt: The Info.txt file can be checked for data counts so that this can be compared if excluding folders, to be sure no pertinent airport or navigation data is excluded.

Exclude.txt: Occasionally addon scenery installations include folders that are not required for the IF10 airports and navdata indexing process. However, since IF10 has to check the folder during the index and route building, these can be excluded manually by adding the folder names preceded with the backslash. See the default file content for more detail; ORBX Global Vector has been excluded as an example.

AIRAC Add-in Navigation Data

(With >augmented upgrade only)

General Procedures Upgraded to >augmented

AIRAC: Aeronautical Information Regulation and Control; refers to the Navigation Database. From the start page choose an AIRAC, choose Integrated if your aircraft uses an AIRAC, if not ignore Integrated. If integrated is chosen the IF10 index should be rebuilt. With Integrated AIRAC, choose AIRAC Bias which uses AIRAC radio frequencies, or Scenery Bias which uses scenery radio frequencies.

SID/STAR: With an AIRAC selected, integrated or not it doesn't matter, from Flight Generator page choose a Plan Type with Approaches, finally on the Mission page choose IDF & SID departure, and FAF & STAR approach.

IF10 handles AIRAC add-in NavData in several different ways.

When an AIRAC Cycle is selected, IF10 can simply use published SID/STAR routes and continue to make plans with the simulator scenery navigation data as normal, while making use of SID/STAR information and inserting waypoints into the plan, SID exit, and STAR entry.

Stock FSX aircraft use navigation data from the simulator scenery. Some aircraft use an add-in navigation database called an AIRAC.

AIRAC Data can be Integrated (Indexed) with the simulator scenery navigation data, to produce routes purely from the AIRAC to match precisely the aircraft navigation systems with AIRAC fed databases, but also using features of the simulator scenery where necessary.

Integration of the AIRAC Cycle Data with the Sim NavData enables IF to choose the most relevant values from both databases, Sim Biased and AIRAC Biased NavData can be chosen.

For example:

"Sim Biased" makes sure the radio frequencies correspond to the sim scenery database.

"AIRAC Biased" makes sure the radio frequencies correspond to the Aircraft NavAid database.

Route finding takes longer with an AIRAC cycle selected. If pure AIRAC routes are not required, the AIRAC can be set to non-integrated (and the scenery re-indexed) while the Cycle remains selected for the planner to find published SID/STAR information.

AIRAC data can usually be found within the FSX program files folder, having been installed along with an add-on aircraft or planner application. If compatible AIRAC Data is found in the chosen directory, the location will be accepted and an invitation to index the scenery is offered. Indexing AIRAC data is not essential, and is only required when plans are to be built entirely from add-in data, for exporting the plan to add-in data fed FMCs.

AIRAC data is indexed and integrated with the sim data when IF10 is required to produce flight plans when an aircraft references its own navigation data. If the aircraft does not use its own navigation data it references the data in the simulator. SID/STAR information from the AIRAC data is used to find waypoints for the approach and departure even though the data is not indexed.

Indexed AIRAC Add-in Navigation Data

AIRAC Biased Data (Red Compass North) can be chosen to ensure coordinates and altitudes are precisely as they are stated in the AIRAC Data, otherwise with SIM Biased Data (Blue Compass North), the simulator scenery, airport coordinate and elevation data, is used for plan locations.

The AIRAC Common Subset can be chosen in the Flight Generator page; this filters out all airports other than those appearing in both the simulator and the AIRAC Data.

To ensure trouble free plans, use the "AIRAC Common Subset", and the "AIRAC Bias" data setting, and use the same issue AIRAC as the aircraft FMC has installed. For example; if you have the PMDG, Level-D 767, or the iFly 737, Aircraft, you could choose the very same dataset for IF10 to use as the aircraft FMC uses itself.

Choose an AIRAC data folder:

Popular AIRAC Folder Locations

  • Aerosoft Airbus X Extended = "C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\aerosoft\Airbus X Extended\NavDataPro".
  • PMDG = "C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\PMDG\NAVDATA".
  • iFly 737 = "C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\iFly\737NG\navdata".
  • Level-D 767 = "C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\Level-D Simulations\navdata".

AIRAC Navigation Data Notes:

AIRAC navigation data differs from the data in the simulator scenery. Generally there are less airports, navaids, and routes in an AIRAC than in the scenery. There may be airports in the AIRAC and not in the scenery, or there may be airports in the scenery but not in the AIRAC.

When the AIRAC is integrated and indexed with the scenery, IF10 compares the AIRAC data and makes a scenery specific subset of airports common to both. Load the AIRAC Common subset on the Flight Gen page. This way you can only make routes between airports that exist in the sim.

When the AIRAC is not integrated and indexed with the scenery, IF10 can still refer to the published SID/STAR records for departures and approaches.

With AIRAC Bias unchecked, IF10 refers to the scenery records for navigation frequencies and runway ILS information. Check the AIRAC Bias menu item (does not need re-indexing) to get the planner and briefing to refer only to the AIRAC supplied data.

Generally the same cycle should be used in all programs and aircraft. The latest cycle is always available from the NavDataPro website for all major add-ons.

Remember to download and install data sets for all your add-ons when purchasing an AIRAC Cycle.

Note: Some aircraft may not like the IF TOC and TOD waypoints or Approach waypoints, if any problems are encountered, please try plans without these added waypoints.

Complimentary AIRAC add-in navigation data set from Aerosoft NavDataPro

Ideal Flight 10 comes with the NavDataPro data set by Aerosoft

A complimentary data set is available for download. The AIRAC is contained in the .zip file "IF10", unzip the contents of this file into the folder: Ideal Flight 10 NavData Zip File.

32bit operating systems: "C:\Program Files\Ideal Flight 10\NavData\NavDataPro\"
64bit operating systems: "C:\Program Files (x86)\Ideal Flight 10\NavData\NavDataPro\"

A current version of the AIRAC dataset is available from Aerosft NavDataPro.

Point the Dataset installer to the IF10 Program Files folder:

32bit operating systems: "C:\Program Files\Ideal Flight 10"
64bit operating systems: "C:\Program Files (x86)\Ideal Flight 10"

Please extract into "C:\Program Files (x86)\Ideal Flight 10". This then makes a directory "...Flight 10\NavData\NavDataPro" and places the files there.

If required download the complimentary data set compressed Zip file, and expand all files and folders into "C:\Program Files (x86)\Ideal Flight 10", making sure to back up any previous data you may have placed there before.

Then in IF10, from the Startup data configuration page popup menu, find this dataset location with the directory picker: "C:\Program Files (x86)\Ideal Flight 10\NavData\NavDataPro"

If you don't intend to integrate the data cancel setting to Integrated, and a re-index is not required.

If you choose to integrate the data, but still want simulator scenery frequencies, uncheck the AIRAC bias in the popup menu, placing the planner into scenery data bias..

SID/STAR Note: From a SID departure or a STAR approach, IF10 chooses the IDF or FAF, and the primary waypoint, to remain compatible with the GPS Plan. Programming an FMC with a SID or STAR is different, a SID or STAR are selected with the FMC keypad. Data comes from the current AIRAC loaded by the aircraft.

Backup and Restore Data

Create backup copies of IF data. Copies all data complete with profiles. The Restore function will preserve or overwrite the License Key information as desired.

You may want to restore a backup onto a new machine, and you may have already registered IF10. If the restore function asks to "Preserve License Key", this means to leave the currently installed License file unchanged. The license information is already available on disk and need not be overwritten by an old registration file from another installation.

If the restore is from an old machine onto an installation on a new machine, do not allow the old registration file to overwrite the new one - Preserve the License Key. If a registration file is from another machine or copy of windows, it will not work and the IF10 program must be re-registered.

Edit Config Files

Start your text editor with IF10 Config.ini or Settings.ini files loaded, for changes to be edited and saved easily.


Special Edition Ideal Flight 10 is the same as regular Ideal Flight 10, but registration of the product is with Flight 1 e-commerce servers instead of codelegend servers.

If you have the Special Edition IF10, codes from original IF10 will not work. Conversely, Special Edition codes will not work with the original IF10 versions. Please contact your supplier for the original version of >augmented if you already own the original IF10 and want to upgrade. If you purchased the Special Edition, and you need the expansion functionality, please ensure you purchase the Special Edition of >augmented to go with it.

Register the key codes online to unlock the IF10 program, and to unlock the >augmented expansion. Register at any time the internet connection is available.

Registration codes must be purchased to use all the Ideal Flight features fully. The registration details can be entered into the registration window, access with the pop-up menu available anywhere in Ideal Flight.

Popup Menu: Registration... Register the IF10 program.

Please put your name in the top box, your IF10 key code in the middle box.

>augmented: Type the IF10 >augmented Upgrade key code in the lower box. Register the >augmented expansion to unlock the upgraded features, with or at any time after registration of the main product key.

If you have the Ideal Flight 10 Special Edition, the Registration window will show descriptions adding "- Special Edition".

Finally press the Register button, or exit from the process with the Skip button.

Problems and Errors

Aircraft not listed in Aircraft Selection Page: Ideal Flight looks in the SimObjects directory and any other directories specified in Settings.ini [AircraftIncludeDirs] section and the fsx.cfg file [Main] section (see FSX documentation).

...adding aircraft folders to IF10 so that they appear in the IF10 Aircraft Selection page:

[AircraftIncludeDirs] Dir3=D:\MyAircraft

With Ai aircraft it is possible that available aircraft locations have altered, or have become unavailable, maybe they have been moved; in these cases, the Ai Selection may need to be re-made in the Mission and Monitor page.

...excluding aircraft folders in IF10 to prevent use as Ai Aircraft:

[AiExcludeDirs] Dir1=SimObjects\Rotorcraft

Errors building Ai Aircraft lists: In this case re-make the Ai Selection in Mission page. In the Flight Generator page, choose the Ai Selection button and uncheck all the aircraft, then make a fresh selection. It is possible your available Ai Aircraft have altered, or they may not be available if they are user aircraft not stored in the FSX SimObjects folder. Ai Aircraft can have other folders specified in fsx.cfg, User aircraft must be stored in the original FSX SimObjects folder or in folders described in fsx.cfg.

FSX Saved Flights: Add-on Aircraft should be able to restore from a saved FSX flight so that "Save/Restore Game", and "Jump To" functions can work correctly.

Missing Airports: Choose checkbox "Show All Airports" in the World Map Page. If the airport shows then, we currently have an aircraft selected with parameters excluding the airport, perhaps a short runway value.

If a scenery problem is suspected, run FSX to make sure the scenery is available and selected in the scenery page, then exit FSX and run IF10 to re-index the scenery.

Errors choosing airports, strange map behaviour, or index out of bounds [0] errors; please try running Index Maintenance from the Startup page Popup Menu.

Some add-on airports may not show their runway ILS. If the ILS does not show, enter the affected ICAO into the text file "ForceMerge.txt" and save with notepad.exe and then re-run the scenery index. ForceMerge.txt is found in the ...ProgramData\Ideal Flight 10\Index folder. Choose "Explore Data" from the Start Page popup menu. Some airports have a missing reference to their runways and the correct ILS's often cannot be assumed, ForceMerge tells IF how certain add-on airports merge with the scenery ILS.

It is possible that FSX can be running but the SimConnect interface has stopped running. After starting a flight and no IF10 Menus are found; close FSX so next time FSX starts the SimConnect interface will start again.

Also see Aircraft Problems and Paused / Pause

When using FSX-SE FSX not installed correctly, or SimConnect version errors: Please ensure that FSX-SE has been run from the desktop icon after any update from Steam, or after changing versions or betas from the Steam menu. After that, before attempting to run IF10, run IF10 Setup and choose Update.

FSX installation or reinstalling FSX or changing the Logged-on Windows User affects the Briefing

The IF10 installation setup program must be run after reinstalling FSX, or changing the logged on user, this ensures that FSX can find the briefing html file.

Run IF setup and allow the update to continue, this only takes a few seconds and ensures the briefing is set up in FSX for the current logged on user.

If you have FSUIPC make sure the AutoSave feature is not renaming the flight. The current FSX flight .FLT, must remain the same name as the plan .PLN, and the kneeboard Briefing .HTM, otherwise FSX cannot display the briefing.

Ideal Flight Program Setup

Installing and Removing

Use the "Locations" button to set the parent folder for the Ideal Flight program folder. This feature is only available during a fresh installation. You must uninstall Ideal Flight from the control panel applet before relocating Ideal Flight. The Profiles folder can be backed up and later merged with a fresh installation or the Restore function can be used if you used the Backup function to copy the settings.

Program Removal provides a button to launch Explorer at the root of the Ideal Flight Data folder. Then the Profiles directory can easily be copied, for example. A backup of the Profiles directory can be copied back over a freshly installed Ideal Flight Profiles directory to restore the profile data. The IF10 Backup function should be used for best results, and is offered prior to the program removal being initiated.

Program Install and Removal provides a menu entry to disable and re-enable the standard thermals file in FSX. This menu function can be used without removing Ideal Flight. Re-run the Ideal Flight installer or run Program Removal to name and re-name the standard thermals file in FSX.

Choose the location of your FSX installation if you have more than one, or if Ideal Flight installer cannot find your FSX installation, which can happen when the FSX registry key has not been updated with a moved FSX location. Ideal Flight Installer will ask to repair the registry if needed.

Note: Airports locations indexing during installation can show up problems in the data if any files are corrupt, in this case try a repair from the DVD before re-installing FSX.

Start Other Programs

Ideal Flight can start other programs during certain periods; there are four periods:

  • With Ideal Flight: When IF10 is finished loading and the Start Page appears.
  • Before starting FS: Just before IF10 starts FS.
  • After starting FS: Just after IF10 starts FS.
  • With simulation: Just after FS has started the actual simulation.

From the IF10 popup menu: Start App Periods are maintained as sequential lists of events, waiting, and starting applications or batch files, one after the other, within the selected period.

Select the application to start with the file locator button, and look for an app_name.exe file, or app_name.bat file, within the program folders of the installed application. Sometimes applications need 'Parameters' entered as start-up commands, e.g. "/restore", these values, or parameters, are written in the 'Parameters' text box provided.

The 'Time Delay' items, add time between applications starting in the same period. Choose Seconds or Milliseconds (1000ths), enter the count in the Parameters text box.

Order the timing of program items with the up and down buttons.

Copy Items: When the "Start Period" of a program item is changed, e.g. from 'With Ideal Flight' to 'Before starting FS', the item is copied to the other period, leaving the original in place. The original Start App program item can be deleted if required.

Config.ini File

There are some values in the Config.ini file that can be edited if required:


  • SESimconnectVersion: Generally, Setup will determine the proper SimConnect version to use. Only use this override if the required SimConnect version is not chosen correctly for FSX-SE. Do not add this, leave blank ("SESimconnectVersion="), or insert with the override version value (e.g. "SESimconnectVersion=10.0.62610.0"), save the file, and then re-run IF10 setup to perform the "Update" process. This will dedicate IF10 during setup to use the specified SimConnect interface if applicable. An invalid value will prevent the program running properly.


  • MinOtherLocationDistance: During indexing, locations other than airports are selected if they are at least MinOtherLocationDistance Nm from airports. The indexes will need updating if this value is changed.
  • AddWaypoints: Include or exclude the waypoints data file with the scenery index. The waypoints.dat file contains an editable list of oceanic waypoints and routes. Sections can be excluded or replaced; new waypoints and routes can be added. See the information in the waypoints.dat file in the Config directory.
  • AddSoftAirports: During scenery indexing, make airport subset "Soft Strips Airports", include only airports with available soft surfaced runways and strips.
  • AddWaterAirports: During scenery indexing, make airport subset "Water Strips Airports", include only airports with available water strips.


  • Proxy: Name or IP Address of a Proxy server (default='blank').
  • TimeOut: Timeout seconds waiting for a response (default=60).


  • ForceDialog: True/False; If Ideal Flight is run at all; always set FSX to start in dialog mode when next started alone.
  • ForceFlight: True/False; If Ideal Flight is run at all; always set FSX to start the default flight when next started alone. Ignored if ForceDialog=True
  • BitmapDir: Default folder for the screenshot bitmaps.
  • PlanDir: Default folder for .PLN plan files. FS9 and FSX files are compatible.
  • FlightFileName: File name used for flight files (.FLT). Please remember to update the installation (re-install) after this item is changed (Default = Ideal_Flight).
  • TidyFSXCFG: True/False; keep fsx.cfg tidy.
  • RunCmd: Run a batch file to start other programs with fsx.exe. The example below shows running from an external frame limiter launched from a batch file (.bat).
  • Params: Command line input parameters for RunCmd.
  • TimeOut: Maximum seconds waiting for FSX to start. Default 1000s (16m 40s).
  • Reconnects: Maximum seconds waiting for FSX to start. Default 10s.
  • FSConfigFilesOverwrite: Overwrite the Config files (dll.xml, exe.xml, fsx.cfg, scenery.cfg) with the constructed files defined on the Aircraft Selection page. (>augmented)
  • FSLogExceptions: Log application errors, also reported on the assessment in Red. (>augmented)
  • FSLogModuleList: Log .DLLs used by the simulator, which could help when diagnosing problems with the simulator setup. (>augmented)
  • FSLogVAS: Log FSX maximum page file memory load, which will normally be seen to increase as objects are introduced during the run of the simulation. (>augmented)
  • FSWarningRemainingVAS: Minimum Bytes remaining from available memory before Peak VAS alarm message is shown. The simulation may crash and exit if all available virtual memory is used.
  • FSLOD=4.5: Write value (e.g. 5.5) to fsx.cfg [TERRAIN] LOD_RADIUS=5.5 before FS starts. Leave blank to do nothing. (>augmented)
  • FSTEX=1024: Write value (e.g. 4096) to fsx.cfg [GRAPHICS] TEXTURE_MAX_LOAD=4096 before FS starts. Leave blank to do nothing. (>augmented)
  • FSJOY=False: Write 0 (False) or 1 (True) to fsx.cfg [CONTROLS] JOYSTICKS=0 or 1, before FS starts, to set the joysticks to disabled or enabled. Leave blank to do nothing, or use "0", "1", "False", or "True".
  • CullObjects: Distant simulated aircraft are analysed, and culled, if it is likely they will not appear during the planned route. Aircraft are ignored if they are leaving or arriving nearby the departure or destination, or the airports along the planned route. (>augmented)
  • CullDistance: Aircraft more than this distance away, are analysed for likelihood of non-appearance en-route, and culled farthest distance from user first. Default distance is set at 64000m, maximum distance is 199Km. (>augmented)
  • CullFromCount: All Ai aircraft more than this amount are automatically culled, farthest distance from user first. Default CullFromCount is set at 199 aircraft.
  • CullInterval: Seconds. Time interval between checks to cull Ai traffic. Default CullInterval sixty seconds.

Note: When using an external program to limit Ai traffic, uncheck the "Full Ai Aircraft Optimisation" box in the "Ai Selection" window, accessed from the Mission page. (>augmented)

FSFullscreenWindow: Full Screen Windowed Mode

Please note: The ALT+ENTER key combination must be used twice to move between "Full Screen Game Mode" and then back to "Window Mode", this invokes the special fullscreen windowed mode, and the window will be Maximized. As the window becomes Maximized, the caption area will disappear to make the window client area fill the screen to appear like a regular fullscreen game mode. The facility will be ON when starting the flight, and toggled to OFF when the "Window Restore" function is used; use Window Restore twice to return the full screen windowed mode back to ON. The main window will attempt to maintain its Maximized state, all the while fullscreen windowed mode is active. (>augmented)

  • FSFullscreenWindow: Set True = enable full screen borderless caption-less windowed mode. Default False. (>augmented)

With Multi-Monitor set up, turn the fullscreen mode off, and move the FSX window (in windowed mode) to the desired screen, then close down FSX to save the monitor setting.

FS Startup and Default Flight

After the simulator has started, and at the corrrect time, FSX affinity is expanded to zero. This gives access to other cores for sub-processes spawned by the sim:

  • ExpandFSAffinity: Default True.

Normally, IF10 starts the simulator with the flight file passed as an argument in the command line, so that the simulator knows which file to load. If FSX is not running when the command is made, the simulator will start up by loading this file rather than the default flight specified in the config.

  • EnableStartupReload: Setting to False will disable reloading the Flight File when IF10 starts a flight, unless the simulator is already running. When the simulator is running, another addon might redirect the flight file to load an alternative saved flight. Set EnableStartupReload=True and EnableStartupReset=True so the flight file will be loaded and the proper saved flight can be resumed. Note: Some complex aircraft must also be paused and manually system files saved so that they can be reloaded when a saved flight is resumed.
  • EnableStartupReset: Setting to False will always disable reloading the Flight File, or the Flight Reset, when IF10 starts a flight. (Other programs can load or restore other flight files in response to the simulator restarting.)
  • LoadDefaultFlight: Setting to True will allow the simulator to load the default flight if IF10 starts the simulator from cold. With this setting, EnableStartupReload and EnableStartupReset have no effect.

It's possible that a particular arrangement of addons on a system may require a specific file be loaded as the first file (default flight) to load into the simulator. The default flight is specified in the FSX.CFG and will be a ".FLT" file:

Editing "C:\Users\[you]\AppData\Roaming\Microsoft\FSX\FSX.CFG"


  • IncludePlanPath: Setting to True will insert the full path of the plan file name into the flight file. A flight and plan file pair can be located and run without the need for editing, since normally, an empty path for the plan file is assumed to be the same folder location from wher the flight file has been loaded. However, with some addons and without the full path inserted, the plan cannot be found and may cause the sim to crash.


Normally, leave these items blank, or do not include them. Otherwise these are file path overrides, and can be used if the FSX setup refers to an unusual folder or config. Ordinary names shown as examples:

  • FSProgramData=
  • FSRoaming=
  • FSCFG=
  • FSDLL=
  • FSEXE=
  • FSDocuments=
    C:\Users\[username]\Documents\Flight Simulator X Files
  • FSScenery=

With some FSX installations, we may want to alter the default ControlTower setup:

FSTowerDir=C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\SimObjects\Misc\ControlTower
FSTowerName=Tower Controller


  • AffinityOverride: Default False. Normally Ideal Flight 10 automatically calculates the CPU Affinity. However, "AffinityOverride" can be set to "AffinityOverride=True" to override the IF10 auto-affinity, and use the AffinityMask or LogicalProcessor settings.
  • AffinityMask: Choose a binary selection of logical processors that may run IF10. At least two must be selected or the mask is ignored. Examples: 3 = enable logical processors 0 and 1, 12 = enable logical processors 2 and 3, 56 = enable logical processors 3, 4, and 5. Set to zero to allow an appropriate logical processor to be automatically chosen for IF10, When the LogicalProcessor setting is to be used leave AffinityMask set to zero. Typically the IF10 logical processors will be those not enabled for FSX, when FSX fsx.cfg has [JOBSCHEDULER] "AffinityMask=" setting enabled.
  • LogicalProcessor A and B: Leave blank or -1 and appropriate logical processors will be chosen for IF10. Otherwise (with AffinityMask=0) set LogicalProcessors A and B to appropriate logical processors [0..N], first=0. Both must be selected or the mask is ignored.

Generally using AffinityMasks is unnecessary and can lead to poor performance. Using these settings in IF10 and FSX can cause problems. If in doubt leave blank or use AM=0. IF10 automatically makes use of the last two logical processors, but may change depending on conditions and core count.

Start Other Programs Affinity: IF10 can control the Affinity of those programs started by Ideal Flight in the "Start Other Programs" Sectionaccessed fromthe startup page popup menu. At the end of the Parameters line add one space and "IF10AM" then an equal sign then the affinity mask decimal value, e.g = " IF10AM=3". Remember to allocate at least two LPs for an app or it can stall. An affinity mask =3 would result in the program being provided two logical processsors, zero and one, on core 0. (>augmented)

Control of FSX expanded affinity can be found in the [FSSetup] section: We can enable or disable "ExpandFSAffinity". After the simulator has started, and at the corrrect time, FSX affinity is expanded to zero. This gives access to other cores for sub-processes spawned by the sim:

  • ExpandFSAffinity: Default True.

How the sim uses CPU cores and logical processors:

The background jobs running behind the sim take seconds to complete, so they are detached from fps. We can set fps almost to what we want, it's governed by the main core speed, or overclock, the screen area, and by setting sliders and features like shadows and water complexity. But don't let something like AA or screen size cap the performance. Keeping AA turned off is a good idea when setting up for performance. Set a small enough screen total size so that the GPU is not capped, that all helps to prevent skewing test results.

So, we can up or down the fps quite easily by changing the image complexity with sliders, or changing the core clock speed or screen size. But what of the background tasks? Handling too many background jobs brings down the performance of the sim. The measure of true performance comes from the combination of fps capability and background throughput. Watching fps is a waste of time, we simply need only set fps to sit as far above the monitor refresh or a division of that frequency as we desire, or the sim can manage, and we're all set; e.g. 60Hz monitor refresh, 1/2=30fps, 1/3=20fps.

The sim is optimised for four cores on a 4GHz class CPU. This seems natural to many people who's games machines generally come with a four core CPU. With a four core CPU we don't need an AM, because the sim will split into the number of Logical Processors it finds = 4. Since the first job requires full bandwidth of a core, it's best to keep other running apps, like exe addons, away from the first core. These can be started with a .bat or an affinity handling program like IF10.

Background throughput and overall performance are reduced when we allow the sim to break into more than four parts. Here's the problem with enabling Hyper Threading. With an HT enabled 4 core the sim will split into eight jobs, one per LP.

We can apply an Affinity Mask (AM) in the cfg to restrict the sim to four jobs, one per core (AM=85=01,01,01,01 or AM=170=10,10,10,10). If we do not use an AM, the first four jobs will occupy the first two cores, other cores will run more jobs of the sim, these will not be used and their data discarded. These excess jobs are redundant in use, and take up extra VAS and generate more heat. All jobs will be running in contention with their Hyper Threaded counterparts sharing throughput of each core.

Once the sim is up and running, and has distributed itself over the available logical processors defined as ones in the mask, and at the right time as the sim starts, IF10 can expand the affinity space to zero. The Expanded FS Affinity (EFSA) allows many other sub-proceses spawned by the sim to run on unused processors.

With HT enabled, we keep exe addons off of core zero (LPs 0 and 1) in the same way. Even addon exe programs will make their first job on the first LP they find available through the mask. They will place the next job on the next LP and that can easily be the same core, just the HT counterpart. We can limit that as we do with the sim, by masking one LP of the first core the addon finds through the mask.

Example fsx.cfg entry for 4 core HT enabled:


AffinityMask=85 (Decimal) = 01,01,01,01 (Binary) = LPs 6,4,2,0 (or reversed 0,2,4,6), LP 7 is on the left, LP 0 on the right hand end)

Example .bat file entries to start exe apps with affinity setting 248:

start /B "" /affinity F8 "C:\Program Files (x86)\FSWeather\FSWeather.exe"
start /B "" /affinity F8 "C:\Program Files (x86)\FSTraffic\FSTraffic.exe"

F8 (Hexadecimal) = 248 (Decimal) = 11,11,10,00 (Binary) = LPs 7,6,5,4,3 (or reversed 3,4,5,6,7), LP 7 is on the left, LP 0 on the right hand end.

Example fsx.cfg entry for 4 core HT enabled and an "aggressive addon":

It's possible some addons may spend a lot of processing time at certain stages of the flight. The application would usually spend most time processing its first thread on the first logical processor it encounters. In these circumstances we might want to keep the addon away from any of the cores utlised by the sim. Since we've only got four cores, we can actually devote just three cores to the sim and get good performance if we are careful. With an appropriate Affinity Mask we can group the second and third jobs onto one core, leaving the first and fourth jobs to cores on their own.


AffinityMask=116 (Decimal) = 01,11,01,00 (Binary) = LPs 6,5,4,2 (or reversed 2,4,5,6), LP 7 is on the left, LP 0 on the right hand end)

Example .bat file entries to start exe apps with affinity settings when reserving a core for addons:

start /B "" /affinity 83 "C:\Program Files (x86)\FSWeather\FSWeather.exe"
start /B "" /affinity 83 "C:\Program Files (x86)\FSTraffic\FSTraffic.exe"

83 (Hexadecimal) = 131 (Decimal) = 10,00,00,11 (Binary) = LPs 7,1,0 (or reversed 0,1,7), LP 7 is on the left, LP 0 on the right hand end.

Example fsx.cfg entry for 6 core HT enabled:


AffinityMask=1360 (Decimal) = 01,01,01,01,00,00 (Binary) = LPs 10,8,6,4 (or reversed 4,6,8,10), LP 11 is on the left, LP 0 on the right hand end)

Example .bat file entries to start exe apps with affinity setting D and E:

start /B "" /affinity D "C:\Program Files (x86)\FSWeather\FSWeather.exe"
start /B "" /affinity E "C:\Program Files (x86)\FSTraffic\FSTraffic.exe"

D (Hexadecimal) = 13 (Decimal) = 00,00,00,00,11,01 (Binary) = LPs 3,2,0 (or reversed 0,2,3), LP 11 is on the left, LP 0 on the right hand end.

E (Hexadecimal) = 14 (Decimal) = 00,00,00,00,11,10 (Binary) = LPs 3,2,1 (or reversed 1,2,3), LP 11 is on the left, LP 0 on the right hand end.

([IFSetup] section continued...)

  • NewOpenDialog: Applies to Windows 8 and later: Set to False to use old style open file dialogs. Windows 10 users may find the old style open file dialog window cannot be resized back to smaller window sizes.
  • MaxFormWidth, MaxFormHeight: Override the maximum available screen resolution for the main form sizes. If they are both specified as larger values than screen size, this will enable the form to spread across multiple monitors, which also disables the form from repositioning onto a monitor whan starting and resizing.

Config.ini File Location

Use the menu item on the start page popup menu (Esc), to edit Config.ini and Settings.ini

Windows XP: see "C:\Documents and Settings\All Users\Application Data\Ideal Flight 10\Config\Config.ini"
Windows Vista and above: see "C:\ProgramData\Ideal Flight 10\Config\Config.ini"

Start FSX with a batch file

A special FS application or FS batch starter with command line parameters has been provided, to be separate from the 'Start Other Apps' lists, (manually edit config.ini):

Open Config.ini FSX directly:

[FSSetup] RunCmd= FSX from a .bat file:

[FSSetup] RunCmd=C:\Program Files (x86)\FPS_Limiter_0.2\fps.bat

example fps.bat contents:

fps_limiter /f:35 "C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\fsx.exe"

Moved FSX Location

If FSX has been moved to another location and run from there, the FSX registry may still point to the original program files location. This registry item is checked and repaired by Ideal Flight 10 during installation and updates, so there is usually no worry.

When Ideal Flight 10 is installed, the installation location is taken from the registry setting. If the FSX program is not found, a dialog will start for the location of FSX to be found.

The FSX registry values can be checked and edited as follows:

64 bit o/s: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\microsoft games\flight simulator\10.0
SetupPath=C:\Program Files (x86)\Microsoft Games\Microsoft Flight Simulator X\

32 bit o/s: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\microsoft games\flight simulator\10.0
SetupPath=C:\Program Files\Microsoft Games\Microsoft Flight Simulator X\

Steam Edition:

64 bit o/s: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\DovetailGames\FSX
exe_path=C:\Program Files (x86)\Steam\SteamApps\common\FSX\fsx.exe
install_path=C:\Program Files (x86)\Steam\SteamApps\common\FSX

exe_path=C:\Program Files\Steam\SteamApps\common\FSX\fsx.exe
install_path=C:\Program Files\Steam\SteamApps\common\FSX

The values must match the file names and folder locations of the FSX program files.