flight_model.cfg

The flight_model.cfg file is an optional aircraft file for defining the flight model of the aircraft. In general, you'll want to prepare this file using the DevMode tools (see here for more information) and then tweak the values if required in the CFG file.

 

Below you can find information on the different sections used in the flight_model.cfg file as well as what parameters and values are expected within them. You can also find an in-depth explanation of the physics behind the flight model from the following page:

NOTE: To help with the configuration of the Flight Model (and the engine.cfg) we have included an *.xlsx file with the documentation that can be used to generate the required values for many of the parameters based on a small number of inputs (these inputs are marked in blue in the file): PlanePerformance.xlsx

 

 

[VERSION]

The [VERSION] section provides version information for the configuration file. In Microsoft Flight Simulator, major versions should always be at least equal to 1. Note that this section information is mandatory and should always be included.

 

Parameter Description Type Required
major Major CFG file version number, values must be greater than 0. Integer Yes
minor Minor CFG file version number, values must be greater than 0. Integer Yes

 

 

[WEIGHT_AND_BALANCE]

This section is used to define the weight and balance of the aircraft. Most position parameters in this section are given relative to the Datum Reference Point for the aircraft, which is itself specified in this section. The convention for positions is that a positive value equals forward, to the right, or vertically upward, and note that all units are in ft, unless mentioned otherwise. Any 3D coordinates are given with respect to this referential in the following order:

  • z (longitudinal) coordinate
  • x (lateral) coordinate
  • y (vertical) coordinate

The only parameters that are not relative to the datum reference are the parameters for the manual longitudinal positioning of the CoL, compute_aero_center and aero_center_lift.

 

The available parameters for this section are:

 

Parameter Description Type Required
max_gross_weight The maximum total weight of the aircraft when fully loaded, in lbs. Float Yes
empty_weight The empty weight of the aircraft, in lbs. Float
reference_datum_position The position of the Datum Reference Point relative to the model center. A three value list - z, x, y - with values in ft.

1D Table of 3 Floats

(see Data Types for more information)

empty_weight_CG_position The position of airplane empty weight CG relative to the Datum Reference Point. A three value list - z, x, y - with values in ft.

1D Table of 3 Floats

(see Data Types for more information)

CG_forward_limit Forward limit of the CG as a Percent Over 100. For example, 0.11 is equal to 11% MAC. Float
CG_aft_limit Aft limit of the CG as a Percent Over 100. For example, 0.4 is equal to 40% MAC. Float
empty_weight_pitch_MOI The empty pitch MOI, in Slug sqft. Float
empty_weight_roll_MOI The empty roll MOI, in Slug sqft. Float
empty_weight_yaw_MOI The empty yaw MOI, in Slug sqft. Float
empty_weight_coupled_MOI The empty transverse MOI, in Slug sqft. Float
activate_mach_limit_based_on_cg

When set to TRUE (1) this activates mach limitation depending on CG position.

Default for most aircraft is FALSE (0).

Bool
activate_cg_limit_based_on_mach

When set to TRUE (1) this activate CG limitation depending on the mach value.

Default for most aircraft is FALSE (0).

Bool
max_number_of_stations The maximum number of payload stations. Integer
station_load.N

This parameter can be used multiple times to define each of the payload stations up to the maximum defined by the max_number_of_stations value (note that counting starts at 0, so for 15 stations N would be from 0 to 14). Parameter takes a comma separated list with the following format:

weight, x, y, z, name, type

The weight is in lbs, (x, y, z) is offset from the Datum Reference Point and in ft, the name is a localisable string, and the type can be one of the following integer values:

- 0 (Unknown)
- 1 (Pilot)
- 2 (Copilot)
- 3 (Passenger)
- 4 (Front Pax)
- 5 (Rear Pax)
- 6 (Baggage)

1D Table of 6 Values

(see Data Types for more information)

No
(Unless max_number_of_stations is greater than 0)
station_name.N

This parameter defines a name that will be used in the payload dialog, and has a 15 character limit. Omission of this will result in a generic station name being used. This parameter can be used multiple times to define names for each of the payload stations up to the maximum defined by the max_number_of_stations value (note that counting starts at 0, so for 15 stations N would be from 0 to 14).

String No
(Unless max_number_of_stations is greater than 0)

 

 

[CONTACT_POINTS]

This section is for defining the points on the aircraft body referential frame which are likely to come in contact with the ground. These parameters are used for aircraft positioning on the ground and also for crash simulations. Full information on the contents of this section can be found from the following page:

 

 

[FUEL]

This section is for defining a simplified fuel system that will reflect on the flight model. In general this section is where you'd define fuel systems for basic aircraft, but for more complex aircraft you have the [FUEL_SYSTEM] section which permits you to setup how fuel will be distributed and used within the aircraft on a much more detailed level. Note that only the fuel_type parameter in this section is still relevant for complex aircraft, and all others can be omitted if you have set up the detailed fuel system.

 

This section has the following parameters:

 

Parameter Description Type Required
LeftMain

Comma separated list of values that defines the tank. List values are:

z, x, y, total_fuel_capacity, unusable_fuel_capacity

(z, x, y) is offset from the Datum Reference Point and in ft, and the fuel capacity values are in Gallons. If any tank is not used, simply supply the list with all values set to 0.

1D Table of 5 Values

(see Data Types for more information)

Yes
RightMain
Center1
Center2
Center3
LeftAux
LeftTip
RightAux
RightTip
External1
External2
fuel_type

The fuel type for the engines.

IMPORTANT! This parameter is the only one from the [FUEL] section that is still required for the modern [FUEL_SYSTEM].

Integer:

  1. 1 = OCTANE 100
  2. 2 = JET A
  3. 3 = OCTANE 80
  4. 4 = AUTO GAS
  5. 5 = JET B
Yes
number_of_tank_selectors The number of tank selectors available, between 1 and 4 only. Integer Yes
electric_pump Whether there is an electric pump (TRUE, 1) or not (FALSE, 0). Bool No
engine_driven_pump Whether there is an engine driven pump (TRUE, 1) or not (FALSE, 0). Bool No
manual_transfer_pump Whether there is a manual transfer pump (TRUE, 1) or not (FALSE, 0). Bool No
manual_pump Whether there is a manual pump (TRUE, 1) or not (FALSE, 0). Bool No
anemometer_pump Whether there is an anemometer pump (TRUE, 1) or not (FALSE, 0). Bool No
fuel_dump_rate The fuel dump rate, as a Percent Over 100. Float No
max_pressure_auto_pump The maximum pressure for the auto pump, in psi. Float No
fuel_transfer_pump.N

Defines a fuel transfer pump N, where N starts at 0. Table contents are:

Source, Destination, Rate in lbs/s, Pump ID

Source and Destination are one of the values given here for the different tanks: Fuel Tank Selection. The Pump ID is an integer value used to identify the pump and link it to a circuit.

To toggle the pump on or off you need to have first created a circuit of the type CIRCUIT_FUEL_TRANSFER_PUMP using the circuit.N parameter of the systems.cfg file, and the circuit Type index needs to be the same as the Pump ID.

The pump can then be toggled on/off using the FUEL_TRANSFER_CUSTOM_INDEX_TOGGLE key event, or using the ELECTRICAL_CIRCUIT_TOGGLE key event.

1D Table of 4 Values

(see Data Types for more information)

No
default_fuel_tank_selector The default fuel selector used in case of autostart, which will override default_fuel_tank_selector.N.

Integer:

  1. 0 = Off
  2. 1 = All
  3. 2 = Left
  4. 3 = Right
  5. 4 = Left Aux.
  6. 5 = Right Aux.
  7. 6 = Center 1
  8. 7 = Center 2
  9. 8 = Center 3
  10. 9 = External 1
  11. 10 = External 2
  12. 11 = Right Tip
  13. 12 = Left Tip
  14. 13 = Crossfeed
  15. 14 = Crossfeed

    Left-to-Right
  16. 15 = Crossfeed

    Right-to-Left
  17. 16 = Both
  18. 17 = All External
  19. 18 = Isolate
  20. 19 = Left Main
  21. 20 = Right Main
No
default_fuel_tank_selector.N Default fuel selector used in case of autostart for engine N, where N corresponds to an engine (between 1 and 4). This will be ignored if default_fuel_tank_selector is defined. Yes
fuel_tank_priority

This is a table of fuel tanks to indicate the order in which they should be used. You list the highest priority first, and thern subseqwuent priorities, for example:

fuel_tank_priority = LeftMain-RightMain, Center1

As you can see, dashes can be used to indicate 2 (or more) fuel tanks sharing the same priority, and in this example both the left and right main tanks are priority 1, then Center1 is priority 2. The following strings can be used to indicate the fuel tanks you want to assign a priority to:

  1. Center1
  2. Center2
  3. Center3
  4. LeftMain
  5. LeftTip
  6. LeftAux
  7. RightMain
  8. RightTip
  9. RightAux
  10. External1
  11. External2

1D Table of Values

(see Data Types for more information)

No

 

 

[FUEL_SYSTEM]

The [FUEL_SYSTEM] section is primarily for use in complex aircraft models where the simple [FUEL] system doesn't give enough control or flexibility for the aircraft systems. The parameters within the [FUEL] section should be used for simple aircraft or those that require a basic fuel system setup, or for maintaining old aircraft (like ones imported from FSX). You can find full details on the fuel system parameters from the following page:

 

 

[AIRPLANE_GEOMETRY]

This section is for defining the geometry of an aircraft. This is a very important part of the Microsoft Flight Simulator flight model since the physics simulation will be based mainly on the actual physical geometry of the aircraft. You can find all the parameters related to the aircraft geometry from the following page:

NOTE: This section is not required if you are creating a Helicopter SimObject.

 

 

[AERODYNAMICS]

This section is where you can set up the various aerodynamic properties for the aircraft. You can find all the parameters related to this section from the following page:

NOTE: This section is not required if you are creating a Helicopter SimObject.

 

 

[FLIGHT_TUNING]

This section is for tuning various aspects of the flight model for an aircraft.

NOTE: This section is not required if you are creating a Helicopter SimObject.

 

The available parameters are:

 

Parameter Description Type Required
modern_fm_only

This can be set to 1 (true) to force the aircraft to use the modern flight model, regardless of what the user may have selected in the Microsoft Flight Simulator options.

Default value is 0 (false).

Boolean No
legacy_fm_only

This can be set to 1 (true) to force the aircraft to use the legacy flight model, regardless of what the user may have selected in the Microsoft Flight Simulator options.

Default value is 0 (false).

Boolean No
empty_CG_deviation_limit

This value allows you to define - in ft - a limit to the maximum deviation that will be allowed in the weight & balance UI menu (where users can change the empty CG position).

Default value is infinite, and it can also can accept 0.

Float No
icing_scalar

With this value you can scale up or down the effects of icing on the plane. This will affects the effect of icing on lift and on the weight.

The default value is 1.0 (100% of the effect). Can accept 0.0 to remove all effects of icing.

Float No
cruise_lift_scalar

Scales the target lift coefficient as looked up from lift_coef_aoa_table over the entire range of AoAs.

Default value is 1.

Float No
parasite_drag_scalar

Scales the target drag coefficient as defined in drag_coef_zero_lift.

Default value is 1.

Float No
induced_drag_scalar

Scales the induced drag target as defined by the target induced drag formula:

\({C}_{Di} = \frac {{C_l} ^{2}} {pi \times AR \times e}\)

This scalar applies to the FLAP 0 configuration (in clean configuration, ie: no propeller, no turbulence, no engine wash, no gears, no flaps, no spoilers, no deflections...).

Default value is 1.

Float No
flap_induced_drag_scalar

Scales the induced drag target as defined by the target induced drag formula:

\({Cd}_{i} = \frac {Cl ^{2}} {pi \times AR \times e}\)

This scalar applies to the FULL FLAP configuration (ldg).

Default value is 1.

Float No
elevator_effectiveness

This scalar scales the elevator_lift_coef parameter in the [AERODYNAMICS] section.

Default value is 1.

Float No
elevator_maxangle_scalar

Scales the deflection angle of the elevator control surface up to the max deflection indicated in elevator_xxx_limit and already scaled by the elevator_elasticity_table.

The default value is 1.0, yet if the limit angles are matching the real aircraft, this scalar should be smaller than one as the effective deflection will be aligned with the overall htail and elevator chord. A value between 0.5 and 0.75 will work with most airplanes.

Float No
aileron_effectiveness

Scales the elevator lift coefficient slope as defined in elevator_lift_coef in the [AERODYNAMICS] section. Increases or decreases elevator authority or "twitchyness" without affecting the deflection angle.

Default value is 1.

Float No
rudder_effectiveness

This scalar scales the rudder_lift_coef parameter in the [AERODYNAMICS] section. Values will increase or decrease lift authority or "twitchyness" without affecting the deflection angle.

Default value is 1.

Float No
rudder_maxangle_scalar

Scales the deflection angle of the rudder control surface up to the max deflection indicated in rudder_limit and already scaled by the rudder_elasticity_table.

The default value is 1, and if the limit angles are matching the real aircraft, this scalar should be less than 1 as the effective deflection will be aligned with the overall vtail and rudder chord. A value between 0.5 and 0.75 will work with most airplanes.

Float No
pitch_stability

Sets a target value for aerodynamic resistance to pitch rotation for the plane. In the legacy flight model, this will scale the pitch_moment_pitch_damping variable. In the modern flight model, this will set a target aerodynamic resistance value that the flight model will try to reach by adding more rotation resistance to each surface. As this system can only add more resistance, there will be a minimum native aerodynamic resistance below which the system can't go. By setting a low target, such as 0.1, the target is usually below the native aerodynamic rotation resistance which means that this parameter will have no effect. To add more aerodynamic resistance, use larger values.

NOTE: Aerodynamic resistance to rotation is relative to the local air mass. If the local airmass is turbulent, increasing rotation resistance will make turbulence impact more on the aircraft.Default value is 1.

Float No
roll_stability

Sets a target value for aerodynamic resistance to roll rotation for the plane. In the legacy flight model, this will scale the roll_moment_roll_damping variable. In the modern flight model, this will set a target aerodynamic resistance value that the modern flight model will try to reach by adding more rotation resistance to each surface. As this system can only add more resistance, there will be a minimum native aerodynamic resistance below which the system can't go. By setting a low target, such as 0.1, the target is usually below the native aerodynamic rotation resistance which means that this parameter will have no effect. To add more aerodynamic resistance, use larger values.

NOTE: Aerodynamic resistance to rotation is relative to the local air mass. If the local airmass is turbulent, increasing rotation resistance will make turbulence impact more on the aircraft.Default value is 1.

Float No
yaw_stability

Sets a target value for aerodynamic resistance to yaw rotation for the plane. In the legacy flight model, this will scale the yaw_moment_yaw_damping variable. In the modern flight model, this will set a target aerodynamic resistance value that the modern flight model will try to reach by adding more rotation resistance to each surface. As this system can only add more resistance, there will be a minimum native aerodynamic resistance below which the system can't go. By setting a low target, such as 0.1, the target is usually below the native aerodynamic rotation resistance which means that this parameter will have no effect. To add more aerodynamic resistance, use larger values.

NOTE: Aerodynamic resistance to rotation is relative to the local air mass. If the local airmass is turbulent, increasing rotation resistance will make turbulence more impacting on the aircraft.Default value is 1.

Float No
pitch_gyro_stability

This variable controls pitch gyroscopic stability. Unlike aerodynamic stability - which is relative to the local airmass - gyroscopic stability is world relative and will not make the aircraft more sensitive to turbulence. It will have the opposite effect in reality: making the aircraft more stable relative to the world, it will become less sensitive to turbulent air. Gyroscopic stability in an aircraft is caused by turning parts such as the propellers or engine axis or turbines.

Default value is 0.

Float No
roll_gyro_stability

This variable controls roll gyroscopic stability. Unlike aerodynamic stability - which is relative to the local airmass - gyroscopic stability is world relative and will not make the aircraft more sensitive to turbulence. It will have the opposite effect in reality: making the aircraft more stable relative to the world, it will become less sensitive to turbulent air. Gyroscopic stability in an aircraft is caused by turning parts such as the propellers or engine axis or turbines.

Default value is 0.

Float No
yaw_gyro_stability

This variable controls yaw gyroscopic stability. Unlike aerodynamic stability - which is relative to the local airmass - gyroscopic stability is world relative and will not make the aircraft more sensitive to turbulence. It will have the opposite effect in reality: making the aircraft more stable relative to the world, it will become less sensitive to turbulent air. Gyroscopic stability in an aircraft is caused by turning parts such as the propellers or engine axis or turbines.

Default value is 0.

Float No
elevator_trim_effectiveness

Scales the elevator trim deflection angle and maximum trim deflection angle as defined in elevator_trim_limit.

Default value is 1.

Float No
aileron_trim_effectiveness

Scales the aileron trim deflection angle and maximum trim deflection angle.

Default value is 1.

Float No
rudder_trim_effectiveness

Scales the rudder trim deflection angle and maximum trim deflection angle as defined in rudder_trim_limit.

Default value is 1.

Float No
aileron_up_drag_scalar

Scales the drag added by upwards aileron deflection as defined in aileron_up_drag_coef parameter in the [AERODYNAMICS] section. This parameter has a significant impact on adverse yaw. Reduce upward deflection drag to get more adverse yaw.

Default value is 1.

Float No
aileron_down_drag_scalar

Scales the drag added by downwards aileron deflection as defined in aileron_down_drag_coef parameter in the [AERODYNAMICS] section. This parameter has a significant impact on adverse yaw. Increase downward deflection drag to get more adverse yaw.

Default value is 1.

Float No
hi_alpha_on_roll

Multiplier on the effects on roll at high angles of attack. This parameter is used in the legacy FSX flight model only to define the stall characteristics of the aircraft. It is not used anymore in the modern flight model.

The default value is 1.

Float No
hi_alpha_on_yaw

Multiplier on the effects on yaw at high angles of attack. This parameter is used in the legacy FSX flight model only to define the stall characteristics of the aircraft. It is not used anymore in the modern flight model.

The default value is 1.

Float No
p_factor_on_yaw

Scales the amount of p-factor induced yaw. P-factor is the result of the propeller providing asymmetric thrust when the propeller is not aligned with the trajectory.

The default value is 1.

Float No
torque_on_roll

Scales the amount of torque that is transmitted from the engine onto the aircraft. When the engine starts to roll into one direction, it will cause the aircraft to roll into the other direction.

The default value is 1.

Float No
gyro_precession_on_pitch

Scales the amount of gyroscopic precession the engine causes on the aircraft's pitch.

The default value is 1.

Float No
gyro_precession_on_yaw

Scales the amount of gyroscopic precession the engine causes on the aircraft's yaw.

The default value is 1.

Float No
engine_wash_on_roll

Scales the impact that the engine wash will have on the control surfaces of the aircraft that causes the aircraft to roll.

The default value is 0.

Float No
wing_engine_wash

Scales the amount of propeller wash that will affect the lift of the part of the wing right behind the propeller.

The default value is 1.

Float No
rudder_engine_wash_on_roll

Scales the amount of added rudder trim compensating engine wash impact on roll. This parameter is separated from the actual rudder trim because it will be disabled with the engine wash on roll depending on piloting assistance's.

The default value is 1.

Float No
wingflex_scalar

Wingflex is based on realistic lift force and gravity computations and default elasticity parameters for a standard wing. This scalar allows to scale the amount of wingflex written to the WING_FLEX_PCT SimVar.

Default value is 1.

Float No
wingflex_surface_scalar

This scalar can be used to modify how the actual aerodynamic surfaces are being flexed by the winglfex force. Set to 1, it should approximately do the correct wingflex, but it will depend on the aircraft wing stiffness.

Default value is 0.

Float No
wingflex_offset Wingflex is based on realistic lift force and gravity computations and default elasticity parameters for a standard wing. This offset allows to offset the amount of wingflex written to the WING_FLEX_PCT SimVar.

Default value is 0.

Float No
stallpitchscalar

This parameter cuts off some of the stalling ability in the modern flight model. In general we don't recommend using anything other than the default value for this parameter, except for aircraft that can fly at extreme AoAs, like delta-wings, for example.

Default value is 1.

Float No
stallliftscalar

Not currently used in Microsoft Flight Simulator

Default value is 1.

Float No
predicted_moi_density_scalar_fuselage

In the Weight debug window, this parameter will impact the predicted MOI that is displayed and can be used to help configure the MOI.

IMPORTANT! This parameter is provided for debug information only and editing it will not affect the flight model.

Default value is 1.

Float No
predicted_moi_density_scalar_wings

In the Weight debug window, this parameter will impact the predicted MOI that is displayed and can be used to help configure the MOI.

IMPORTANT! This parameter is provided for debug information only and editing it will not affect the flight model.

Default value is 1.

Float No
disable_assistances

When set to 1 (TRUE) this will disable all available assistances for the aircraft.

Default value is 0 (FALSE).

Bool No
prop_moment_transfer_on_roll

This parameter allows you to scale how much of the propeller acceleration moment is transferred back to the aircraft body. Note that this does not apply to the absorbed torque, only to the RPM acceleration moment.

Default value is 0.

Float No
ground_crosswind_effect_zero_speed

This parameter represents the world speed (in ft per second) at which 0% of the crosswind effect is applied to the aircraft. This parameter will work in two different ways:

  • With the ground rudder assistance enabled, at the given speed and below, the lateral (x) component of the wind is set to zero.
  • With the ground rudder assistance disabled, crosswind is completely cancelled out below ground_crosswind_effect_zero_speed ft per seconds of IAS, and it is gradually blended in up to 100% at ground_crosswind_effect_max_speed ft per seconds of IAS.

Note that this value can be set to -1000 to have a 100% realistic simulation where the crosswind is never cancelled out. 

Default value is 5.

Float No
ground_crosswind_effect_max_speed

This parameter represents the world speed (in ft per second) at which 100% of the crosswind effect is applied to the aircraft.

Note that this value can be set to -1000 to have a 100% realistic simulation where the crosswind is never cancelled out. 

Default value is 80.

Float No
ground_high_speed_steeringwheel_static_friction_scalar

At high speeds, tires are rolling and - depending on their shape and width and how much they are inflated - they will more or less resist rotation or sideways motion. This parameter allows you to define how much a moveable wheel resists static friction which goes sideways or resists rotation around the vertical axis. Essentially, it allows you to control how much the aircraft will move into the crosswind when rolling at higher speeds, and reducing the scalar will reduce the friction, so the aircraft is more likely to slide. Note that only the lateral forces are impacted by this value, so rolling friction and braking when your aircraft is rolling straight will not be influenced.

Default value is 1.

Float No
ground_high_speed_otherwheel_static_friction_scalar

At high speeds, tires are rolling and - depending on their shape and width and how much they are inflated - they will more or less resist rotation or sideways motion. This parameter allows you to define how much a non-moveable wheel resists static friction which goes sideways or resists rotation around the vertical axis. Essentially, it allows you to control how much the aircraft will move into the crosswind when rolling at higher speeds, and reducing the scalar will reduce the friction, so the aircraft is more likely to slide. Note that only the lateral forces are impacted by this value, so rolling friction and braking when your aircraft is rolling straight will not be influenced.

Default value is 1.

Float No

 

 

[REFERENCE SPEEDS]

This section contains various reference speed values used in different systems across the sim like the Flight Assistant, the Aircraft Selection UI, notifications, or overspeed triggers. Most of these parameters will have no direct effect on the flight model.

 

The available parameters are:

 

Parameter Description Type Required
full_flaps_stall_speed

Speed at which the aircraft will stall when flaps are at full, in kias.  Used in the Flight Assistant.

Default value is 0.

Float No
flaps_up_stall_speed

Speed at which the aircraft will stall when flaps are up, in kias.  Used in the Flight Assistant.

Default value is 0.

Float No
cruise_speed

The aircraft cruise speed, in ktas. Used in aircraft selection UI

Default value is 0.

Float No
cruise_mach

The aircraft cruise speed, in Mach

Default value is 0.

Float No
crossover_speed

The aircraft crossover speed, in kias.

Default value is 0.

Float No
max_mach

The maximum speed for the aircraft, in Mach. Used in aircraft selection UI.

NOTE: Only valid for Jet and Turboprop engines.

Default value is 0.9.

Float No
max_indicated_speed

The maximum speed indicated in the aircraft UI, in kias.

Default value is 0.

Float No
max_flaps_extended

The maximum aircraft speed with flaps extended, in kias. Used in the Flight Assistant.

Default value is 0.

Float No
normal_operating_speed

The normal operating speed of the aircraft, in kias. Used in aircraft selection UI.

Default value is 0.

Float No
airspeed_indicator_max

The maximum airspeed indicator value in the UI, in kias.

Default value is 0.

Float No
rotation_speed_min

The minimum rotation speed required, in Knots.

Default value is -1.

Float No
climb_speed

The aircraft climb speed, in Knots. Used to define spawning conditions.

Default value is 0.

Float No
cruise_alt

The aircraft cruise altitude, in ft.

Default value is 1500.

Float No
takeoff_speed

The aircraft takeoff speed, in Knots.

Default value is 55.

Float No
spawn_altitude

The spawn altitude, in ft.

Default value is 1500.

 

Float No
spawn_cruise_altitude

The spawn cruise altitude, in ft. Used to define spawning conditions.

Default value is 1500.

Float No
spawn_descent_altitude

The spawn descent altitude, in ft. Used to define spawning conditions.

Default value is 500.

Float No
best_angle_climb_speed

The best angle climb speed, in Knots.

Default value is 0.

Float No
approach_speed

The required approach speed, in Knots.

Default value is 0.

Float No
best_glide

The best glide speed, in Knots.

Default value is 0.

Float No
max_gear_extended

The maximum speed with landing gear extended, in Knots.

Default value is 0.

Float No
best_single_engine_rate_of_climb_speed

This is the best single-engine rate of climb speed (the Blue line speed, \(V_{yse}\) ), in Knots.

Default value is 0.

Float No
minimum_control_speed

This is the speed below which aircraft control cannot be maintained if the critical engine fails under a specific set of circumstances (generally known as the \(V_{mc}\) ). Value is in Knots.

Default value is 0.

Float No
fly_assistant_use_dynamic_speeds

This parameter refers to how the UI will display the relevant reference speeds for takeoff, climb, etc... When set to 1 (TRUE), the values will by dynamically generated by the simulation, and when set to 0 (FALSE) the values in the CFG file will be used. Note that this has no effect on the flight model.

Default is 0 (FALSE). 

Bool No

 

 

[STALL PROTECTION]

Stall protection is a system which prevents the AoA from getting too high. This is done by software monitoring the plane's angle of attack sensor, and when a high alpha situation is detected, the software lowers the nose of the plane to maintain a high - but still safe - AoA. This system is designed to prevent pilots from stalling the aircraft and to allow them to get the best possible performance in emergency e.g. in a wind-shear.

NOTE: This section requires that the fly_by_wire parameter is enabled, as the stall protection is currently only available to FBW aircraft. If that parameter is set to false, none of the parameters in this section are used.

The following parameters can be used to control this system:

 

Parameter Description Type Required
stall_protection

Whether Stall Protection is enabled (TRUE, 1) or not (FALSE, 0).

Default is 0.

Bool No
off_limit

Alpha below which the Stall Protection can be disabled, in degrees (if also below off_yoke_limit).

Default is 0.

Float
off_yoke_limit

Yoke position percentage below which the Stall Protection can be disabled (if also below off_limit).

Default is 0.

Float
on_limit

Alpha - in degrees - above which the Stall Protection timer starts.

Default is 0.

Float
on_goal

The alpha - in degrees - that the Stall Protection will attempt to reach when triggered.

Default is 0.

Float
timer_trigger

Duration, in seconds, that the alpha must be above on_limit before the Alpha Protection is triggered.

Default is 0.

Float

 

 

[FLAPS.N]

This section is for tuning the different flaps for the aircraft. You can have multiple [FLAPS.N] sections where N relates to the flap being defined from 0 up to the number of flaps - 1. For example, if you have two flaps you would have two sections, [FLAPS.0] and [FLAPS.1].

 

The available parameters are:

 

Parameter Description Type Required
type

Defines the flaps type.

Integer:

  1. 0 = none
  2. 1 = trailing edge
  3. 2 = leading edge
Yes
system_type Defines the type of electrical system that drives the flaps to deflect.

Integer:

  1. 0 = electrical
  2. 1 = hydraulic
  3. 2 = pneumatic
  4. 3 = manual
  5. 4 = none
Yes
system_type_index

If using electrical flaps, this parameter specifies the index of the flaps motor circuit.

Default is 0.

Integer No
span-outboard

Outboard span area, as a Percent Over 100 This is how far out from the wing-root that the flaps stretch (the total span is considered as the distance between wing root and wing tip). On most planes this will be 1.0 - aileron_span_outboard. This value needs to be matching the lift and drag added by flaps. Small flap systems should add small amounts of lift.

Default value is 0.75, and note that any input value given is clamped between 0.4 and 1.0.

IMPORTANT! Despite the flaps span being defined in each flap section, the span is common to all the simulation will take the maximum span value defined in flap sections and clamp it between 0.4 and 1.0

Float No
extending-time

Time it takes for the flap set to extend to the fullest deflection angle specified (in seconds).

Default value is 0.

Float No
flaps-sequence-increasing

If set, this specifies that these flaps should only start moving towards the down position when the flaps with the corresponding index have finished moving.

Default is -1, which means no such restriction should be applied.

Integer No
flaps-sequence-decreasing

If set, this specifies that these flaps should only start moving towards the up position when the flaps with the corresponding index have finished moving.

Default is -1, which means no such restriction should be applied.

Integer No
damaging-speed

Speed above which the flaps begins to get damaged, if extended, in Knots.

Default value is 0, which means no damage will be applied, regardless of the speed.

Float No
blowout-speed

Speed above which the flaps are blown out, in Knots.

Default value is 0, which means no blowouts will occur, regardless of the speed.

Float No
maneuvering_flaps

Sets whether maneuvering flaps are available (TRUE, 1) or not (FALSE, 0).

Default value is 0 (FALSE).

Bool No
delay_between_flap_index

 

Default value is 0.

Float No
lift_scalar

Scalar that allows you to scale the lift contribution of a specific flap system. This is necessary to compensate for the scale by the deflection angle in radians, in order to reach 100%, ie: the computed lift coefficient is multiplied by the surface deflection, so you need to compensate for this deflection if it's inferior to 1 radian to reach 100% of your lift coefficient. 
The flap lift formula is the following:

total_flap_lift = lift_coef_flaps * (system1.lift_scalar * system1.deflectionangleradians + system2.lift_scalar * system 2.deflectionangleradians...)

Default value is 1.

Float No
drag_scalar

Scalar that allows you to scale the drag contribution of a specific flap system. It is necessary to compensate for the scale by the deflection angle in radians, in order to reach 100%, ie: the computed drag coefficient is multiplied by the surface deflection, so you need to compensate for this deflection if it's inferior to 1 radian to reach 100% of your drag coefficient.
The flap drag formula is the following:

total_flap_drag = drag_coef_flaps * (system1.drag_scalar * system1.deflectionangleradians + system2.drag_scalar * system 2.deflectionangleradians...)

Default value is 1.

Float No
pitch_scalar

The percentage of total pitch due to flap deflection that this flap set is responsible for at full deflection.

This is a legacy FSX parameter not used in the modern flight model. In the modern flight model, the pitch generated by flaps will depend on the lift added and the longitudinal position of the wings. The parameters of each flap level allow to move the wing longitudinally for each flap level to adjust the amount of pitch.

Default value is 1.

Float No
max_on_ground_position The maximal flap extension stage available when an aircraft is on the ground. This must be a value between 0 and the maximal stage described (see flaps-position.N). Integer No
altitude-limit

Specifies an altitude (in ft) above which the flaps cannot be extended.

Default is -1, which disables the feature.

Float No
flaps-position.i

This is a flap stage description, and you can have multiple definitions (starting at flaps-position.0) for each [FLAPS.N] section. The table of values takes the following 7 values in the given order:

  • flap position - sets the flaps angular position for the stage, in degrees.
  • airspeed limit - sets the airspeed limit for the stage, in Knots.
  • drag scalar - sets a scalar to add or remove drag for the stage.
  • lift scalar - sets a scalar to add or remove lift for the stage.
  • area scalar - sets a scalar to add or remove area to the flap for the stage.
  • add camber - sets an increase in the flap camber, raising the maximum lift coefficient or the upper limit to the lift a wing can generate.
  • add aft feet - sets the center of lift for the flaps stage, where a positive value will move the center of lift forward (generating more pitch up) and a negative value will move it back (generating more pitch down).
  • add incidence - sets an increase in the angle of incidence - which is the difference between the longitudinal axis of the aircraft and the chord line of the wing - in degrees.

1D Table of Floats

(see Data Types for more information)

Yes

flaps-position-inhibit-or.i

Alias:

flaps-position-inhibit.i

This is a comma separated table of conditions which - if any of them are valid - will inhibit the flaps settings from affecting the flaps at position i. There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1. Can be any of the following:

  1. "air" - plane is in the air
  2. "ground" - plane is on the ground
  3. "increasing" - inhibit only if rising flaps level
  4. "decreasing" - inhibit only if decreasing flaps level

By default this is set to "", "", "", "".

1D Table of Strings

(see Data Types for more information)

No
flaps-position-inhibit-and.i

This is a coma separated table of conditions which - if all of them are valid - will inhibit the flaps settings from affecting the flaps at position i. There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1. Can be any of the following:

  1. "air" - plane is in the air
  2. "ground" - plane is on the ground
  3. "increasing" - inhibit only if rising flaps level
  4. "decreasing" - inhibit only if decreasing flaps level

By default this is set to "", "", "", "".

1D Table of Strings

(see Data Types for more information)

No
flaps-position-autoretract.i

This parameter sets the auto-retract rules for flaps. There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1. The parameter requires a comma separated table of values in the following order:

  1. - the flaps angle in degrees
  2. - the airspeed in Knots at which the auto-retract triggers
  3. - the new airspeed limit, in Knots

1D Table of Floats

(see Data Types for more information)

Yes
flaps-position-maneuvering.i

When set to 1 (TRUE) flaps position i will have a dynamic maneuvering flaps behavior rather than a static degree value. Set to 0 (FALSE) to disable this feature for the flaps. There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1.

Boolean No
flaps-position-speed-factor.i

This parameter requires a table of values that set the correspondence between the speed (in Knots) of the plane and a factor (from 0 - 1) on the max angle of the flaps position i. For example:

flaps-position-speed-factor.0 = 0:1, 150:1, 240:0 ;

Here, between 0 and 150 you get the full flaps position, but above 150 it starts getting reduced linearly until 240 at which point it's 0.

There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1.

2D Table of Floats

(see Data Types for more information)

No
flaps-position-speed-override-above.i

This parameter sets the override rules for flaps at the given position when above a certain speed. There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1. The parameter requires the following two values, separated by a comma:

  • the flaps position to use as the override
  • the speed (in Knots) above which the given flaps position is used instead of the current one.

1D Table of Floats

(see Data Types for more information)

No
flaps-position-speed-override-below.i

This parameter sets the override rules for flaps at the given position when below a certain speed. There can be multiple entries for this parameter, one for each flaps position, with i starting at 0 and up to number of positions - 1. The parameter requires the following two values, separated by a comma:

  • the flaps position to use as the override
  • the speed (in Knots) below which the given flaps position is used instead of the current one.

1D Table of Floats

(see Data Types for more information)

No

 

 

[INTERACTIVE POINTS]

Interactive Points are used to define the position of various doors of the aircraft as well as some other points to interact with Airport Services, such as the end of a fuel hose to interact with a FuelTruck. You can find full information on this section on the following page:

 

 

[HELICOPTER]

This section is for setting up the various helicopter-specific components of the flight model. If you are modelling a helicopter then this section is essential, and is used - along with the [FUSELAGE_AERODYNAMICS], [MAINROTOR] and [SECONDARYROTOR] sections - to define the flight model, and including this usually means there is no need to include data for the [FLIGHT_TUNING][AERODYNAMICS] and [AIRPLANE_GEOMETRY] sections. Full information can be found on the following page:

 

 

[FUSELAGE_AERODYNAMICS]

This section is for setting up the aerodynamics of a helicopter fuselage, and as such should only be included in the CFG file when creating a helicopter SimObject. Full information can be found on the following page:

 

 

[MAINROTOR]

This section is for setting up the main rotor of a helicopter, and as such should only be included in the CFG file when creating a helicopter SimObject. Full information can be found on the following page:

 

 

[SECONDARYROTOR]

This section is for setting up the secondary rotor of a helicopter, and as such should only be included in the CFG file when creating a helicopter SimObject. Full information can be found on the following page: