FLT File Properties

The <mission_name>.flt file goes in the main mission folder beside the other files and is formatted like CFG Files and can be edited by using any text editor. This file is responsible for what happens when the mission is launched, and tells the simulation which files to use and which not, as well as setting basic parameters like plane selection. It’s also in charge of all the information displayed in the simulation briefing screen.

Below you can find information on the different sections used in the <mission_name>.flt file as well as what parameters and values are expected within them. Note that all file paths in the <mission_name>.flt are relative to the directory the FLT file resides in, and some of the sections listed will only be used on certain types of flights - such as missions - and the exact number of sections will depend on the type of aircraft being flown.

You can find an overview of how to create and edit FLT files on the following page:

• FLT Files

You can find an example of this kind of file on the following page:

• Complete FLT Example

[Main]#

This section is used for defining certain items of meta-data related to the flight or mission that the files is defining. The available parameters are:

[Briefing]#

In this section you can setup how the mission briefing should look. The available parameters are:

[Options]#

In this section you can set some miscellaneous options for the flight. The available parameters are:

[Assistance]#

This section of the FLT file is used to override the different assistance options and show notifications. Certain missions - for example, Landing Challenges - will require that the user performs actions unassisted and so you can use the parameters in this section to disable specific assistance options that would normally be available in the simulation options menu. Note that if this section is not used, the activity will use the assistance’s set by the user.

The available parameters are:

For more information on Event Triggers see the following page:

• Event Trigger Definitions

[AutoPilot.N]#

There will be one autopilot entry for each aircraft. The available parameters are:

[EFIS]#

The EFIS (electronic flight information system) entry corresponds to the Visual Flight Path dialog. This is simply the visual aid given to identify the route the pilot should be following. The available parameters are:

[ObjectFile]#

This entry will be present when a mission is saved off, or it can be added to define the files used by a mission (when multiple XML files are used). The available parameters are:

[FreeFlight]#

Set the freeflight state. The available parameters are:

[NIGHT_VISION]#

In this section you can control certain aspects of the night-vision system for the aircraft. The available parameters are:

[Weather]#

This section controls the way the weather will be created for the flight. The available parameters are:

[BingMap]#

This section controls certain online interactions between the simulation and BingMaps(opens in a new tab). The available parameters are:

[Departure]#

Set the departure airport. The available parameters are:

[Arrival]#

Set the arrival airport. The available parameters are:

[Loading]#

Set one or more images for loading the flight along with one or more accompanying tips text. The available parameters are:

[TrafficManager]#

This section controls the offline traffic manager. The available parameter is:

[LivingWorld]#

This section controls the offline traffic manager. The available parameters are:

[User Tip Window]#

This section controls the window for user tips. The available parameters are:

[Atc_Menu]#

This section is related to the ATC menu window. The available parameters are:

[ATC_AgentManager]#

This section is for defining the number of ATC agents within the simulation. The available parameter is:

[ATC_AircraftManager]#

This defines the number of aircraft in the ATC manager. The available parameters are:

[ATC_MessageSystem]#

Sets up the ATC message system. The available parameters are:

[ATC_Agent.N]#

There will be an [ATC_Agent] entry for each agent, which can be none in free flight.

[ATC_Aircraft.N]#

This section is for defining properties to specific aircraft involved in the flight. The available parameters are:

[ATC_AircraftData.N]#

There will be an [ATC_AircraftData.N] entry for each aircraft flying with a flight plan, which can be none in free flight. When adding this entry, each one should be given a unique number, starting at 0. The available parameters are:

[ATC_ActiveFlightPlan.N]#

This entry will exist if the user aircraft is flying with a current flight plan, either IFR or VFR. Note that This section is only necessary if your mission has an active flightplan, and the parameter ActiveFlightPlan of the section [ATC_Aircraft.N] must be set to True. The available parameters are:

[ATC_RequestedFlightPlan.N]#

This entry will only be present if the user aircraft has requested a new flight plan, and has yet to receive confirmation that this flight plan has been cleared. In some cases a flight file will have both an [atc_activeflightplan.N] and an [atc_requestedflightplan.N] (when a change from one flight plan to another has been requested), and in others just either one of these entries. The property list is identical to that of [ATC_ActiveFlightPlan.N].

[ATC_FrequencyNode.N]#

Defines an ATC frequency node to be used with the ATC message system. The available parameters are:

[ATC_MessageNode.N.i]#

A message node for the ATC message system. The available parameters are:

[GPS_Engine]#

A [GPS_Engine] entry will be present if the user aircraft is flying under ATC rules - IFR or VFR - and has an active flightplan. The available parameters are:

[Covers]#

This section is related to the preflight checks that are done to prepare an aircraft before takeoff. Each parameter relates to a cover or item that needs to be removed before the aircraft can fly, and as such this section and its parameters is only required in the hangar.flt and apron.flt. For more information, please see the following page:

• Preflight

[Dirt.N]#

This section can be added to define the quantity of dirt, grime and general wear and tear the aircraft show show when spawned. The available parameters are:

[DateTimeSeason]#

Sets the date, time and seasonal details for the flight. The available parameters are:

[Camera.N.i]#

These sections are used for setting a camera for the flight and there can be a large number of these entries in every FLT file. The section is numbered using the following format:

Camera.<window number>.<camera number>

The available parameters for each of these sections are:

[SimplifiedSim.N]#

This sets an optimised simulation type for the AI aircraft in the simulation. The available parameters are:

[Sim.N]#

There will be one sim entry for each sim object saved off. This will include one entry for the user aircraft, and one for each mission object. If mission objects are saved off then each one is noted by one [Sim.n], [SimVars.N], [Slew.N] and [Freeze.N] entry. The available parameters are:

[Panel.N]#

For the user aircraft there is a [Panel.N] entry for every panel, such as the main panel, radio stack, GPS, throttle controls, and so on. The panels are numbered from 1, and will be in the same order that they appear in the Panel Configuration Files. The available parameters are:

[Avionics.N]#

There will be one avionics entry for each aircraft. The available parameters are:

[Slew.N]#

There will be a slew entry for each simulation object saved off. In slew mode an object is simply being moved at a constant speed in various directions or orientations. Some, but not all, information on the slew movement is preserved in the [SimVars.N] section. The available parameters are:

[Freeze.N]#

If the aircraft is under control from a SimConnect addon, for example, then the simulator is instructed not to alter certain parameters by “freezing” it out. The available parameters that can be frozen are:

[SystemFailureN.i]#

Optional entries. These will only be present if one or more system failures are set, which can be from a mission. The first number (N) is the index of the failure, indexed from 0. The second number (i) is the aircraft reference, usually 0 for the user aircraft. So the first entry is usually [SystemFailure0.0], followed by [SystemFailure1.0], and so on. There can be up to 1000 failures on an aircraft. The available parameters that can be frozen are:

[Engine Parameters.N.i]#

There is one of these entries for each engine, so - for example - a Cessna will have one entry, and a Boeing 747 will have four. The first number (N) is the engine number, starting at 1, and the second (i) is the aircraft number (0 for the user aircraft). The available parameters are:

[Propeller.N.i]#

There is one of these entries for each propeller, and the first number (N) is the engine number that the propeller belongs to - starting at 1 - and the second (i) is the aircraft number (0 for the user aircraft). The available parameters are:

[HYDRAULICS_SYSTEM_EX1.N]#

This section is for setting the parameters required by the modular hydraulics system. These are only required if the [HYDRAULICS_SYSTEM_EX1] section has been set up for the aircraft. The available parameters are:

[FuelSystem.N]#

This section is for setting the parameters required by the modular fuel system. These are only required if the [FUEL_SYSTEM] section has been set up for the aircraft. The available parameters are:

[PNEUMATIC_SYSTEM_EX1.N]#

This section is for setting the parameters required by the modular pneumatic system. These are only required if the [PNEUMATIC_SYSTEM_EX1] section has been set up for the aircraft, and even then they may be omitted if you wish to have the aircraft in its default state.

The available parameters are:

[Electrical.N]#

This section sets up the electrical system for an aircraft. There should be one [Electrical.N] entry per aircraft. The available parameters are:

[Liquid Dropping System.N]#

There will be one entry of the liquid dropping system for each aircraft that requires it.

The available parameters are:

[Water Ballast System.N]#

There will be one entry of the liquid dropping system for each aircraft that requires it.

The available parameters are:

[Burner_System.N]#

There will be one entry of the burner system for each aircraft that requires it.

The available parameters are:

[Switches.N]#

There will be one switches entry for each aircraft. The available parameters are:

[Systems.N]#

There will be one systems entry for each aircraft. The available parameters are:

[Airship_System.N]#

This section is only used when the aircraft is an airship. It is used to setup the flight state of the airship for the step of the flight that the FLT refers to. The available parameters are:

[Gauges.N]#

There will be one gauges entry for each aircraft. The available parameters are:

[BleedAir.N]#

Setup the bleed air system for the engines on an aircraft, one entry for each aircraft. The available parameters are:

[Navigation_Graph.N]#

There will be one payload entry for each aircraft. The available parameters are:

[CabinService.N]#

This section can be added when the flight or mission requires the use of some Navigation Service. The section is indexed from 0, and if you need to define multiple navigation services for the aircraft or mission, then you can add more sections, incrementing the index N by 1 each time.

The available parameters are:

[CabinServiceObject.N]#

This section can be added to define a single behaviour object that will be used as part of a Navigation Service. The section is indexed from 0, and if you need to define multiple objects, then you can add more sections, incrementing the index N by 1 each time. These objects will usually be spawned by a mission file using the <SimMission.CreateCabinServiceObject> element.

The available parameters are:

[InteractivePoints.N]#

There will be one interactive point section per-aircraft. The available parameters are:

[WEAR_AND_TEAR_SYSTEM.N]#

There will be one failure system entry for each aircraft. The available parameters are:

[Controls.N]#

There will be one controls entry for each aircraft. The available parameters are:

[SimVars.N]#

There will be one SimVars entry for each SimObject saved off. The available parameters are:

[LocalVars.N]#

This section can be used to define and initialise un-scoped local variables to be used in missions. Localvars will be defined here using the same format as the rest of the options that exist in the configuration files, eg: varname = value. Unlike the local variables created in the [LocalVars] section of the systems.cfg file these variables are not persisted between runs. To access these variables in the code you need to use the “L:” var identifier using Reverse Polish Notation, and if you are using the JavaScript API then this is done using the same function as for SimVars: GetSimVarValue(name, unit, dataSource = ""). These variables are shared between aircraft if multiple instances of the aircraft are spawned. In general this is not what you want and you should use the scoped L:1 variable type instead, defined in the [LocalVars_EX1.N] section.

[LocalVars_EX1.N]#

This section can be used to define and initialise scoped local variables to be used in missions. Localvars will be defined here using the same format as the rest of the options that exist in the configuration files, eg: varname = value. Unlike the local variables created in the [LocalVars] section of the systems.cfg file these variables are not persisted between runs. To access these variables in the code you need to use the “L:1” var identifier using Reverse Polish Notation, and if you are using the JavaScript API then this is done using the same function as for SimVars: GetSimVarValue(name, unit, dataSource = ""). These variables are scoped to each instance of the aircraft that use them, so each instance will have a unique version of the local variables you define in this section (unlike the un-scoped L var type defined in the [LocalVars.N] section).

Note that the convention used in the MSFS 2024 model behaviors is to prefix all these variables with XMLVAR_*, for example:

[LocalVars_EX1.0]
XMLVAR_COVER_WING_LEFT=0
XMLVAR_COVER_WING_RIGHT=0

[SimScheduler]#

This section is for setting some very specific simulation parameters that will affect the way the simulation runs. The available parameters are:

Obsolete Parameters#

In this section we list the parameters that are obsolete in Microsoft Flight Simulator 2024, and can therefor be removed from your FLT files.

[Options]#

[Atc_Menu]#

[SimVarForSpawningInTheAir]#

This section can be added when the flight or mission is designed to start with the aircraft in the air, rather than on the ground. Note that adding this section will cause some of the other *.flt file parameters to be overridden. This happens because when you have this section then start the simulation, the engine has to try and balance the plane using the requested configuration so it can start flying immediately. As such this will mean that some system and engine parameters will be overwritten.

The available parameters are: