Aircraft Engine Variables

AIRCRAFT ENGINE VARIABLES

The table below indicates the properties for the Simulation Variables that can be used to get and set properties related to the engines of an aircraft. For information on the units listed for each variable, please see here: Simulation Variable Units

NOTE: When Microsoft Flight Simulator 2024 is running in multiplayer mode, only a small number of variables are communicated between aircraft. Those variables that are available will say so in the description as being either for "All Aircraft" or for "Shared Cockpit". Also note that in the multiplayer "Shared Cockpit" mode the only supported index is 1, which means that the data is assumed to be identical for all engines.

You can find a complete index of all available SimVars here: SimVar Index

NOTE: Many of the SimVars listed here require an engine index. This is a value between 1 and 16 that signals which of the engines on the aircraft is being targeted to get or set the value for the SimVar.

Simulation Variable	Index	Description	Units
`BLEED AIR ENGINE`	Engine Index	Returns whether or not the indexed engine (see note) attempts to provide bleed air.	Bool
`BLEED AIR SOURCE CONTROL`	Engine Index	The bleed air system source controller for an indexed engine (see note). This will work as follows: When engines and APU are activated, it will return 0 because it is in Auto. If the APU is removed, it will return 3 for engines only. If instead the engines are removed, it would return 2 for the APU only. If the APU and engines are removed, it would return 1 (so, off).	Enum: 0 = auto 1 = off 2 = apu 3 = engines
`COWL FLAPS`	N/A	Deprecated, do not use!	Percent Over 100
`ENGINE CONTROL SELECT`	N/A	Selected engines (combination of bit flags)	Flags: 1 = Engine 1 2 = Engine 2 4 = Engine 3 8 = Engine 4
`ENGINE MIXURE AVAILABLE`	N/A	True if engine mixture is available for prop engines. Deprecated, do not use (mixture is always available)!	Bool
`ENGINE PRIMER`	Engine Index	The engine primer position. Deprecated, do not use!	Position
`ENGINE TYPE`	N/A	Engine type.	Enum: 0 = Piston 1 = Jet 2 = None 3 = Helo(Bell) turbine 4 = Unsupported 5 = Turboprop 6 = Electric
`ENG ANTI ICE`	Engine Index	Anti-ice switch for the indexed engine (see note), true if enabled false otherwise.	Bool
`ENG COMBUSTION`	Engine Index	True if the indexed engine (see note) is running, false otherwise.	Bool
`ENG CYLINDER HEAD TEMPERATURE`	Engine Index	The indexed engine (see note) cylinder head temperature.	Rankine
`ENG EXHAUST GAS TEMPERATURE`	Engine Index	Exhaust gas temperature for the indexed engine (see note).	Rankine
`ENG EXHAUST GAS TEMPERATURE GES`	Engine Index	Governed engine setting exhaust gas temperature for the indexed engine (see note).	Percent Over 100
`ENG FAILED`	Engine Index	Failure flag for the indexed engine (see note) that has failed.	Bool
`ENG FUEL FLOW BUG POSITION`	Engine Index	Fuel flow reference in pounds per hour for the indexed engine (see note).	Pounds per hour
`ENG FUEL FLOW GPH`	Engine Index	Engine fuel flow in gallons per hour for the indexed engine (see note).	Gallons per hour
`ENG FUEL FLOW PPH`	Engine Index	The indexed engine (see note) fuel flow in pounds per hour.	Pounds per hour
`ENG FUEL FLOW PPH SSL`	Engine Index	Engine fuel flow in pounds per hour. Deprecated in favour of `ENG FUEL FLOW PPH`.	Pounds per hour
`ENG HYDRAULIC PRESSURE`	Engine Index	The indexed engine (see note) hydraulic pressure. This SimVar is for use with the legacy [HYDRAULIC_SYSTEM] . Note that this will still work for the current modular hydraulics system, but will require a name instead of an index as it simply replicates the `HYDRAULIC PUMP PRESSURE` SimVar.	Pounds per square foot (psf)
`ENG HYDRAULIC QUANTITY`	Engine Index	The indexed engine (see note)hydraulic fluid quantity, as a percentage of total capacity. This SimVar is only for use with the legacy [HYDRAULIC_SYSTEM] .	Percent Over 100
`ENG MANIFOLD PRESSURE`	Engine Index	The indexed engine (see note) manifold pressure.	Inches of mercury (inHg)
`ENG MAX RPM`	Engine Index	The indexed engine (see note) Maximum rpm.	RPM
`ENG N1 RPM`	Engine Index	The indexed engine (see note) N1 rpm.	RPM (0 to 16384 = 0 to 100%)
`ENG N2 RPM`	Engine Index	The indexed engine (see note) N2 rpm.	RPM (0 to 16384 = 0 to 100%)
`ENG OIL PRESSURE`	Engine Index	The indexed engine (see note) oil pressure.	pounds per square foot (psf)
`ENG OIL QUANTITY`	Engine Index	The indexed engine (see note) oil quantity as a percentage of full capacity.	Percent Over 100
`ENG OIL TEMPERATURE`	Engine Index	The indexed engine (see note) oil temperature.	Rankine
`ENG ON FIRE`	Engine Index	The indexed engine (see note) on fire state.	Bool
`ENG PRESSURE RATIO`	Engine Index	The indexed engine (see note) pressure ratio.	Ratio (0-16384)
`ENG PRESSURE RATIO GES`	Engine Index	Engine pressure ratio. Deprecated, do not use!	Scalar
`ENG RPM ANIMATION PERCENT`	Engine Index	The indexed engine (see note) percentage maximum rated rpm - used for visual animation. NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`ENG RPM SCALER`	Engine Index	RPM scalar value. Deprecated, do not use!	Scalar
`ENG TILT PITCH`	Engine Index	This represent the indexed engine (see note) pitch angle relative to it's base orientation, in radians. Values here are clamped between the minimum and maximum values given by the `TiltMinAngles.N` and `TiltMaxAngles.N` parameters.	Radians
`ENG TILT PITCH PERCENT`	Engine Index	This is the indexed engine (see note) pitch angle expressed as a +/- Percent Over 100 between the minimum and maximum values given by the `TiltMinAngles.N` and `TiltMaxAngles.N` parameters. The values -1.0 to 0.0 are the from the minimum angle to 0, and the values 0.0 to 1.0 are from 0 to the maximum angle.	Percent Over 100
`ENG TILT PITCH PERCENT EX1`	Engine Index	This is the indexed engine (see note) pitch angle expressed as a +/- Percent Over 100 between the minimum and maximum values given by the `TiltMinAngles.N` and `TiltMaxAngles.N` parameters. Here the 0.0 value is the minimum angle, and 1.0 is the maximum angle, meaning that a value of 0.5 is not 0 radians, but will be the 50% position between the minimum and maximum radians.	Percent Over 100
`ENG TILT YAW`	Engine Index	This represent the indexed engine (see note) yaw angle relative to it's base orientation, in radians. Values here are clamped between the minimum and maximum values given by the `TiltMinAngles.N` and `TiltMaxAngles.N` parameters.	Radians
`ENG TILT YAW PERCENT`	Engine Index	This is the indexed engine (see note) yaw angle expressed as a Percent Over 100 between the minimum and maximum values given by the `TiltMinAngles.N` and `TiltMaxAngles.N` parameters. The values -1.0 to 0.0 are the from the minimum angle to 0, and the values 0.0 to 1.0 are from 0 to the maximum angle.	Percent Over 100
`ENG TILT YAW PERCENT EX1`	Engine Index	This is the indexed engine (see note) yaw angle expressed as a +/- Percent Over 100 between the minimum and maximum values given by the `TiltMinAngles.N` and `TiltMaxAngles.N` parameters. Here the 0.0 value is the minimum angle, and 1.0 is the maximum angle, meaning that a value of 0.5 is not 0 radians, but will be the 50% position between the minimum and maximum radians.	Percent Over 100
`ENG TORQUE`	Engine Index	The indexed engine torque (see note) .	Foot pounds
`ENG VIBRATION`	Engine Index	The indexed engine (see note) vibration.	Number
`ESTIMATED FUEL FLOW`	Engine Index	Estimated fuel flow to the indexed engine (see note) at cruise speed.	Pounds per hour
`FULL THROTTLE THRUST TO WEIGHT RATIO`	N/A	Full throttle thrust to weight ratio	Number
`GENERAL ENG ANTI ICE POSITION`	Engine Index	The indexed engine (see note) anti-ice switch state - 0 (FALSE) is off and 1 (TRUE) is on.	Bool
`GENERAL ENG COMBUSTION`	Engine Index	Set the indexed engine (see note) combustion flag to TRUE or FALSE. Note that this will not only stop all combustion, but it will also set the engine RPM to 0, regardless of the actual state of the simulation. NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	Bool
`GENERAL ENG COMBUSTION EX1`	Engine Index	This SimVar is similar to `GENERAL ENG COMBUSTION`, in that it can be used to enable or disable combustion on an indexed engine (see note). This SimVar will not interfere with the current state of the simulation. For example, if the aircraft has a turbine engine with `auto_ignition` enabled or it's a propeller engine with magnetos, then in the subsequent simulation frames this SimVar may be set to 1 (TRUE) again as the engine restarts automatically.	Bool
`GENERAL ENG COMBUSTION SOUND PERCENT`	Engine Index	Percent of maximum sound being created by the indexed engine (see note). NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`GENERAL ENG DAMAGE PERCENT`	Engine Index	Percent of total damage to the indexed engine (see note).	Percent
`GENERAL ENG ELAPSED TIME`	Engine Index	Total elapsed time since the indexed engine (see note) was started.	Hours
`GENERAL ENG EXHAUST GAS TEMPERATURE`	Engine Index	The indexed engine (see note) exhaust gas temperature.	Rankine
`GENERAL ENG FAILED`	Engine Index	The indexed engine (see note) fail flag.	Bool
`GENERAL ENG FIRE DETECTED`	Engine Index	Detects if a fire has been detected in an indexed engine (see note) or not. If 0 (FALSE) no fire has been detected and if 1 (TRUE) then it has. No longer used in the simulation.	Bool
`GENERAL ENG FUEL PRESSURE`	Engine Index	The indexed engine (see note) fuel pressure.	Pounds per square inch (psi
`GENERAL ENG FUEL PUMP ON`	Engine Index	Whether the indexed engine (see note) fuel pump on (1, TRUE) or off (0, FALSE).	Bool
`GENERAL ENG FUEL PUMP SWITCH`	Engine Index	Fuel pump switch state the indexed engine (see note). If 0 (FALSE) the pump is off and if 1 (TRUE) then it is on.	Bool
`GENERAL ENG FUEL PUMP SWITCH EX1`	Engine Index	Equivalent to `GENERAL ENG FUEL PUMP SWITCH` but differentiates between ON and AUTO	Bool
`GENERAL ENG FUEL USED SINCE START`	Engine Index	Fuel used since the indexed engine (see note) was last started.	Pounds
`GENERAL ENG FUEL VALVE`	Engine Index	Fuel valve state for the indexed engine (see note). If 0 (FALSE) then the valve is closed and if 1 (TRUE) then it is open.	Bool
`GENERAL ENG GENERATOR ACTIVE`	Engine Index	Settable alternator (generator) on/off switch for the indexed engine (see note).	Bool
`GENERAL ENG GENERATOR SWITCH`	Engine Index	Alternator (generator) on/off switch state for the indexed engine (see note).	Bool
`GENERAL ENG HOBBS ELAPSED TIME`	Engine Index	This can be used to find the time since the indexed engine (see note) started running. Similar to `ElapsedTachometerTime`, this records the time the engine has been running, but instead of taking a % of the time based on the Pct/RPM this takes the full time, but only if a threshold RPM/speed is reached. You can set the thresholds using the `accumulated_time_hobbs_min_pct_rpm` and `accumulated_time_hobbs_min_knots` parameters in the `[GENERALENGINEDATA]` section of the `engines.cfg` file.	Seconds
`GENERAL ENG MASTER ALTERNATOR`	Engine Index	The alternator switch for a specific engine. Requires an engine index (1 - 4) when used.	Bool
`GENERAL ENG MAX REACHED RPM`	Engine Index	Maximum attained rpm for the indexed engine (see note).	RPM
`GENERAL ENG MIXTURE LEVER POSITION`	Engine Index	Percent of max mixture lever position for the indexed engine (see note).	Percent
`GENERAL ENG OIL LEAKED PERCENT`	Engine Index	Percent of max oil capacity leaked for the indexed engine (see note).	Percent
`GENERAL ENG OIL PRESSURE`	Engine Index	The indexed engine (see note) oil pressure.	Psf
`GENERAL ENG OIL TEMPERATURE`	Engine Index	The indexed engine (see note) oil temperature.	Rankine
`GENERAL ENG PCT MAX RPM`	Engine Index	Percent of max rated rpm for the indexed engine (see note). NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`GENERAL ENG PROPELLER LEVER POSITION`	Engine Index	Percent of max prop lever position for the indexed engine (see note).	Percent
`GENERAL ENG REVERSE THRUST ENGAGED`	Engine Index	This will return 1 (TRUE) if the reverse thruster is engaged, or 0 (FALSE) otherwise.	Bool
`GENERAL ENG RPM`	Engine Index	The RPM for an indexed engine (see note). NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	RPM
`GENERAL ENG STARTER`	Engine Index	The indexed engine (see note) starter on/off state.	Bool
`GENERAL ENG STARTER ACTIVE`	Engine Index	True if the indexed engine (see note) starter is active. NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Bool
`GENERAL ENG THROTTLE LEVER POSITION`	Engine Index	Percent of max throttle position for the indexed engine (see note).	Percent
`GENERAL ENG THROTTLE MANAGED MODE`	Engine Index	Current mode of the managed throttle for the indexed engine (see note).	Number
`MASTER IGNITION SWITCH`	N/A	Aircraft master ignition switch (grounds all engines magnetos).	Bool
`MAX EGT`	N/A	The maximum EGT, as set using the `egt_peak_temperature` parameter in the `engines.cfg` file.	Rankine
`MAX OIL TEMPERATURE`	N/A	The maximum oil temperature, as set using the parameter `oil_temp_heating_constant` in the `engines.cfg` file.	Rankine
`MAX RATED ENGINE RPM`	Engine Index	Maximum rated rpm for the indexed engine (see note).	RPM
`NUMBER OF ENGINES`		Number of engines (minimum 0, maximum 4)	Number
`OIL AMOUNT`	Engine Index	Deprecated, do not use!	FS7 Oil Quantity (Deprecated)
`PANEL AUTO FEATHER SWITCH`	Engine Index	Auto-feather arming switch for the indexed engine (see note). Please see the for more information.	Bool
`PROP AUTO CRUISE ACTIVE`	Engine Index	True if prop auto cruise active	Bool
`PROP AUTO FEATHER ARMED`	Engine Index	Auto-feather armed state for the indexed engine (see note).	Bool
`PROP BETA`	Engine Index	The "prop beta" is the pitch of the blades of the propeller, and this can be used to retrieve the current pitch setting, per indexed engine (see note).	Radians
`PROP BETA FORCED ACTIVE`	Engine Index	This can be used to enable the propeller forced beta mode (1, TRUE) or disable it (0, FALSE), when being written to. When being read from, it will return TRUE (1) if the forced beta mode is enabled or FALSE (0) if it isn't. When enabled, the `PROP BETA FORCED POSITION` value will be used to drive the prop beta, while the internal coded simulation logic is used when this is disabled.	Bool
`PROP BETA FORCED POSITION`	Engine Index	Get or set the target beta to which the prop is forced. This value will be approximated during the simulation at a rate of 5°/second. Note that this "forcing" will respect the `beta_max` limit (but will ignore the `beta_min`). Only valid when `PROP BETA FORCED ACTIVE` is TRUE (1).	Radians
`PROP BETA MAX`	N/A	The "prop beta" is the pitch of the blades of the propeller. This retrieves the maximum possible pitch value for all engines.	Radians
`PROP BETA MIN`	N/A	The "prop beta" is the pitch of the blades of the propeller. This retrieves the minimum possible pitch value for all engines.	Radians
`PROP BETA MIN REVERSE`	N/A	The "prop beta" is the pitch of the blades of the propeller. This retrieves the minimum possible pitch value when the propeller is in reverse for all engines.	Radians
`PROP DEICE SWITCH`	Engine Index	True if prop deice switch on for the indexed engine (see note).	Bool
`PROP FEATHERED`	Engine Index	This will return the feathered state of the propeller for an indexed engine (see note). The state is either feathered (true) or not (false).	Bool
`PROP FEATHERING INHIBIT`	Engine Index	Feathering inhibit flag for the indexed engine (see note).	Bool
`PROP FEATHER SWITCH`	Engine Index	Prop feather switch for the indexed engine (see note).	Bool
`PROP LOCK`	Engine Index	Returns whether the indexed engine (see note) propeller is locked (true) or not (false).	Bool
`PROP MAX RPM PERCENT`	Engine Index	Percent of max rated rpm for the indexed engine (see note). NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`PROP ROTATION ANGLE`	N/A	Prop rotation angle. NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Radians
`PROP RPM`	Engine Index	Propeller rpm for the indexed engine (see note).	RPM
`PROP SYNC ACTIVE`	Engine Index	True if prop sync is active the indexed engine (see note).	Bool
`PROP SYNC DELTA LEVER`	Engine Index	Corrected prop correction input on slaved engine for the indexed engine (see note).	Position
`PROP THRUST`	Engine Index	Propeller thrust for the indexed (see note) engine. The value returned by this SimVar will depend on the `prop_mod_version` parameter, where: Version < 2: the value will be calculated using the legacy propeller simulation. Version >= 2: the value will be calculated using the modern propeller simulation. NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Pounds
`PROPELLER ADVANCED SELECTION`	N/A	Deprecated, do not use!	Enum (Deprecated)
`SHUTOFF VALVE PULLED`	N/A	This checks if the shutoff valve to the engine has been pulled (true) or not (false). When pulled piston engines will be blocked from getting any fuel.	Bool
`THROTTLE INPUT BLOCKED BY LOWER BOUNDS`	Engine Index	Settable boolean triggering the notification for the indexed throttle blocked at the lower bounds when user tries to go past it. When requested with no index parameter, the SimVar will return 1 (TRUE) if any engine index throttle is true. When trying to set the SimVar with no index, then all engine throttles will be set to the specified value.	Bool
`THROTTLE INPUT BLOCKED BY UPPER BOUNDS`	Engine Index	Settable boolean triggering the notification for the throttle blocked at the upper bounds when user tries to go past it. When requested with no index parameter, the SimVar will return 1 (TRUE) if any engine index throttle is true. When trying to set the SimVar with no index, then all engine throttles will be set to the specified value.	Bool
`THROTTLE LOWER LIMIT`	N/A	Percent throttle defining lower limit (negative for reverse thrust equipped airplanes).	Percent
`TURB ENG AFTERBURNER`	Engine Index	Afterburner state for the indexed engine (see note). NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Bool
`TURB ENG AFTERBURNER PCT ACTIVE`	Engine Index	The percentage that the afterburner is running at. NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent Over 100
`TURB ENG AFTERBURNER STAGE ACTIVE`	Engine Index	The stage of the afterburner, or 0 if the afterburner is not active. NOTE: This is available in multiplayer to all near aircraft. See here for more information: Note On SimVars In Multiplayer.	Number
`TURB ENG ANIMATION RPM`	Engine Index	This returns an extrapolated RPM value for the indexed engine which is used to drive the turbine animation model behaviour template. This value is calculated as: $$\frac{N1}{100} \times \textrm{N1_100pc_rpm}$$ If the `N1_100pc_rpm` is not defined, then the SimVar will return the `GENERAL ENG RPM` value.	RPM
`TURB ENG BLEED AIR`	Engine Index	Bleed air pressure for the indexed engine (see note).	Pounds per square inch (psi
`TURB ENG COMMANDED N1`	Engine Index	Effective commanded N1 for the indexed turbine engine (see note). The way this value is calculated will depend on the following: For a jet engine the calculation depends on the `use_commanded_Ne_table` parameter: If true, the return value is calculated depending on `use_n2_to_n1_table`, commanded Ne and inlet Mach. If false, the return value is equal to commanded Ne. For a turbo-prop or helo-turbine engine the return value is calculated depending on throttle position and mixture control. Also note that while this SimVar is writable, the written information will be overridden by the simulation on the very next frame.	Percent
`TURB ENG CONDITION LEVER POSITION`	Engine Index	When the throttle is on idle position, this sets the condition levers to one of 3 positions to define the idle N1 target for the indexed engine (see note): Down position is the cut-off position that cuts the fuel to the engine, effectively shutting down the engine. Middle position requires N1 to reach the low idle value when throttle is in idle position (low idle value can be checked using the `TURB_ENG_LOW_IDLE` SimVar). High position requires N1 to reach the high idle value when throttle is in idle position (high idle value can be checked using the `TURB_ENG_HIGH_IDLE` SimVar). Note that this option requires several settings from the engines.cfg file to be set to specific values before working correctly: `DisableMixtureControls` needs to be set to 1 (TRUE). `tp_idle_range` should be set to 0 (since there is no mixture setting). and `idle_high_fuel_flow` must be set to the same value (since there is no mixture setting to induce a variation between the 2). and `high_idle_n1` to be correctly set.	Enum: 0 = fuel cut-off 1 = low idle 2 = high idle
`TURB ENG CORRECTED FF`	Engine Index	Corrected fuel flow for the indexed engine (see note).	Pounds per hour
`TURB ENG CORRECTED N1`	Engine Index	The indexed turbine engine (see note) corrected N1.	Percent
`TURB ENG CORRECTED N2`	Engine Index	The indexed turbine engine (see note) corrected N2.	Percent
`TURB ENG FREE TURBINE TORQUE`	Engine Index	The amount of free torque for the indexed turbine engine (see note).	Foot Pound
`TURB ENG FUEL AVAILABLE`	Engine Index	True if fuel is available for the indexed engine (see note).	Bool
`TURB ENG FUEL EFFICIENCY LOSS`	Engine Index	This is used to control the fuel efficiency loss of the indexed engine, from 0 - no fuel efficiency loss - to 100 - double the fuel consumption.	Percent
`TURB ENG FUEL FLOW PPH`	Engine Index	The indexed engine (see note) fuel flow rate.	Pounds per hour
`TURB ENG HIGH IDLE`	Engine Index	Retrieves the high idle N1 value to be reached by the the indexed turboprop engine (see note) with throttle in idle position and condition lever in high idle position (condition lever position can be checked or set using the `TURB_ENG_CONDITION_LEVER_POSITION` SimVar).	Percent
`TURB ENG IGNITION SWITCH`	Engine Index	True if the the indexed turbine engine (see note) ignition switch is on.	Bool
`TURB ENG IGNITION SWITCH EX1`	Engine Index	Position of the the indexed turbine engine (see note) Ignition Switch. Similar to `TURB_ENG_IGNITION_SWITCH` but differentiates between ON and AUTO.	Enum: 0 = OFF 1 = AUTO 2 = ON
`TURB ENG INLET TEMPERATURE`	Engine Index	This SimVar exposes the value of the total temperature at the engine inlet, calculated as: $$\textrm{total_temperature} = OAT \times (1 + 0.2 \times M^2)$$ Where: $OAT$ is the outside (ambient) air temperature in Rankine. $M$ is defined as: Aircraft Mach number when `supersonic_inlet` is 1 (true). Inlet Mach number when `supersonic_inlet` is 0 (false)	Rankine
`TURB ENG IS IGNITING`	Engine Index	Whether or not the ignition system is currently running for the indexed engine (see note). Depends on `TURB_ENG_IGNITION_SWITCH_EX1` Enum, the cfg var `ignition_auto_type` and current state of the plane.	Bool
`TURB ENG ITT`	Engine Index	Retrieve or set the ITT for the indexed engine (see note).	Rankine
`TURB ENG ITT COOLING EFFICIENCY LOSS`	Engine Index	This is used to control the ITT cooling efficiency loss of the indexed engine, from 0 - no cooling efficiency loss - to 100 -engine recieves no ITT cooling.	Percent
`TURB ENG JET THRUST`	Engine Index	The indexed engine (see note) jet thrust.	Pounds
`TURB ENG LOW IDLE`	Engine Index	Retrieves the low idle N1 value to be reached by the the indexed turboprop engine (see note) with throttle in idle position and condition lever in low idle position (condition lever position can be checked or set using the `TURB_ENG_CONDITION_LEVER_POSITION` SimVar).	Percent
`TURB ENG MASTER STARTER SWITCH`	Engine Index	True if the turbine engine master starter switch is on, false otherwise.	Bool
`TURB ENG MAX TORQUE PERCENT`	Engine Index	Percent of max rated torque for the indexed engine (see note).	Percent
`TURB ENG N1`	Engine Index	The indexed turbine engine (see note) N1 value. NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`TURB ENG N1 LOSS`	Engine Index	This is used to control the N1 loss of the indexed engine, from 0 - no N1 loss - to 100 - 100% N1 loss.	Percent
`TURB ENG N2`	Engine Index	The indexed turbine engine (see note) N2 value. NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`TURB ENG NUM TANKS USED`	Engine Index	Number of tanks currently being used by the indexed engine (see note).	Number
`TURB ENG PRESSURE RATIO`	Engine Index	The indexed engine (see note) pressure ratio.	Ratio
`TURB ENG PRIMARY NOZZLE PERCENT`	Engine Index	Percent thrust of primary nozzle for the indexed engine (see note).	Percent Over 100
`TURB ENG REVERSE NOZZLE PERCENT`	Engine Index	Percent thrust reverser nozzles deployed for the indexed engine (see note). NOTE: This is available in multiplayer to all far aircraft. See here for more information: Note On SimVars In Multiplayer.	Percent
`TURB ENG TANKS USED`	Engine Index	Fuel tanks used by the indexed engine (see note), one or more of the following bit flags: Center 1 Bit 0 Center 2 Bit 1 Center 3 Bit 2 Left Main Bit 3 Left Aux Bit 4 Left Tip Bit 5 Right Main Bit 6 Right Aux Bit 7 Right Tip Bit 8 External 1 Bit 9 External 2 Bit 10	Mask
`TURB ENG TANK SELECTOR`	Engine Index	Fuel tank selected for the indexed engine (see note). See Fuel Tank Selection for a list of values.	Enum
`TURB ENG THROTTLE COMMANDED N1`	Engine Index	The indexed turbine engine (see note) commanded N1 for current throttle position.	Percent
`TURB ENG THRUST EFFICIENCY LOSS`	Engine Index	This can be used to control the thrust efficiency loss of the indexed engine, where a value of 0 is 100% of available thrust, and 100 is 0% available thrust.	Percent
`TURB ENG VIBRATION`	Engine Index	The indexed turbine engine (see note) vibration value.	Number
`TURB MAX ITT`	N/A	Retrieve the itt_peak_temperature as set in the engines.cfg file.	Rankine

Reciprical (Piston) Engine Vars

The following SimVars are only valid for piston engines:

Simulation Variable	Index	Description	Units
`RECIP CARBURETOR TEMPERATURE`	Engine Index	Carburetor temperature the indexed engine (see note).	Celsius
`RECIP ENG ALTERNATE AIR POSITION`	Engine Index	Alternate air control the indexed engine (see note).	Position
`RECIP ENG ANTIDETONATION TANK MAX QUANTITY`	Engine Index	The maximum quantity of water/methanol mixture in the ADI tank for the indexed engine (see note). This value is set as part of the `[ANTIDETONATION_SYSTEM.N]` section in the aircraft configuration files.	Gallons
`RECIP ENG ANTIDETONATION TANK QUANTITY`	Engine Index	The quantity of water/methanol mixture currently in the ADI tank for the indexed engine (see note).	Gallons
`RECIP ENG ANTIDETONATION TANK VALVE`	Engine Index	The status of the ADI tank valve for the indexed engine (see note).	Bool
`RECIP ENG ANTIDETONATION FLOW RATE`	Engine Index	This gives the actual flow rate of the Anti Detonation system for the indexed engine (see note).	Gallons per hour
`RECIP ENG BRAKE POWER`	Engine Index	Brake power produced by the indexed engine (see note).	Foot pounds (ftlbs) per second
`RECIP ENG BRAKE POWER PCT`	Engine Index	Brake power produced by the indexed engine expressed as a percent over 100. (see note).	Percent Over 100
`RECIP ENG COOLANT RESERVOIR PERCENT`	Engine Index	Percent coolant available for the indexed engine (see note).	Percent
`RECIP ENG COWL FLAP POSITION`	Engine Index	Percent cowl flap opened for the indexed engine (see note).	Percent
`RECIP ENG CYLINDER HEAD TEMPERATURE`	Engine Index	Engine cylinder head temperature for the indexed engine (see note).	Celsius
`RECIP ENG CYLINDER HEALTH`	Engine Index	Index high 16 bits is engine number, low16 cylinder number, both indexed from 1.	Percent Over 100
`RECIP ENG DETONATING`	Engine Index	Set to 1 (TRUE) if the indexed engine (see note) is detonating.	Bool
`RECIP ENG EMERGENCY BOOST ACTIVE`	Engine Index	Whether emergency boost is active (1, TRUE) or not (0, FALSE) for the indexed engine (see note).	Bool
`RECIP ENG EMERGENCY BOOST ELAPSED TIME`	Engine Index	The elapsed time that emergency boost has been active on the indexed engine (see note). The timer will start when boost is first activated. IMPORTANT! This timer does not reset. So if you set your time limit in the `engines.cfg` file to 315s and you spend 2 minutes with boost active, then pull back on the throttle for 1 minute, then engage boost again for 2 minutes, the simulation will consider that you spent 4 minutes with boost active. The 1 minute pause is not taken into account.	Hours
`RECIP ENG ENGINE MASTER SWITCH`	Engine Index	Whether or not the Engine Master switch is active on an indexed engine (see note).	Bool
`RECIP ENG FUEL AVAILABLE`	Engine Index	True if fuel is available for the indexed engine (see note).	Bool
`RECIP ENG FUEL FLOW`	Engine Index	The indexed engine (see note) fuel flow.	Pounds per hour
`RECIP ENG FUEL NUMBER TANKS USED`	Engine Index	Number of tanks currently being used by the indexed engine (see note).	Number
`RECIP ENG FUEL TANKS USED`	Engine Index	Fuel tanks used by the indexed engine (see note), one or more of the following bit flags: Center 1 Bit 0 Center 2 Bit 1 Center 3 Bit 2 Left Main Bit 3 Left Aux Bit 4 Left Tip Bit 5 Right Main Bit 6 Right Aux Bit 7 Right Tip Bit 8 External 1 Bit 9 External 2 Bit 10	Mask
`RECIP ENG FUEL TANK SELECTOR`	Engine Index	Fuel tank selected for the indexed engine (see note). See Fuel Tank Selection for a list of values.	Enum
`RECIP ENG GLOW PLUG ACTIVE`	Engine Index	Whether or not the Glow Plug is active on the indexed engine (see note)..	Bool
`RECIP ENG LEFT MAGNETO`	Engine Index	Left magneto state for the indexed engine (see note).	Bool
`RECIP ENG MANIFOLD PRESSURE`	Engine Index	The indexed engine (see note) manifold pressure.	Pounds per square inch (psi
`RECIP ENG NITROUS TANK MAX QUANTITY`	Engine Index	The maximum quantity of nitrous permitted per indexed engine (see note).	Gallons
`RECIP ENG NITROUS TANK QUANTITY`	Engine Index	The quantity of nitrous per indexed engine (see note).	Gallons
`RECIP ENG NITROUS TANK VALVE`	Engine Index	The statt of the nitrous tank valve for the indexed engine (see note). Either 1 (TRUE) for open or 0 (FALSE) for closed.	Bool
`RECIP ENG NUM CYLINDERS`	Engine Index	The number of cylinders for the indexed engine (see note).	Number
`RECIP ENG NUM CYLINDERS FAILED`	Engine Index	The number of cylinders that have failed in the indexed engine (see note).	Number
`RECIP ENG PRIMER`	Engine Index	The indexed engine (see note) primer state.	Bool
`RECIP ENG RADIATOR TEMPERATURE`	Engine Index	The indexed engine (see note) radiator temperature.	Celsius
`RECIP ENG RIGHT MAGNETO`	Engine Index	The indexed engine (see note) right magneto state.	Bool
`RECIP ENG STARTER TORQUE`	Engine Index	Torque produced by the indexed engine (see note).	Foot pound
`RECIP ENG SUPERCHARGER ACTIVE GEAR`	Engine Index	Returns which of the supercharger gears is engaged for the indexed engine (see note).	Number
`RECIP ENG TURBINE INLET TEMPERATURE`	Engine Index	The indexed engine (see note) turbine inlet temperature.	Celsius
`RECIP ENG TURBOCHARGER FAILED`	Engine Index	The indexed engine (see note) turbo failed state.	Bool
`RECIP ENG WASTEGATE POSITION`	Engine Index	When the `engines.cfg` parameter `turbocharged` is TRUE, this SimVar will return the percentage that the turbo waste gate is closed for the indexed engine (see note). If the turbocharged variable is FALSE and the `manifold_pressure_regulator` parameter is TRUE, then this will return the percentage that the manifold pressure regulator is closed for the indexed engine.	Percent
`RECIP MAX CHT`	N/A	This will return the cylinder head temperature value set by the `cht_heating_constant` parameter in the `engines.cfg` file.	Rankine
`RECIP MIXTURE RATIO`	Engine Index	Fuel / Air mixture ratio for the indexed engine (see note).	Ratio

Fuel Tank Selection

Number	Description
`0`	Off
`1`	All
`2`	Left
`3`	Right
`4`	Left auxiliary
`5`	Right auxiliary
`6`	Center
`7`	Center2
`8`	Center3
`9`	External1
`10`	External2
`11`	Right tip
`12`	Left tip
`13`	Crossfeed
`14`	Crossfeed left to right
`15`	Crossfeed right to left
`16`	Both
`17`	External
`18`	Isolate
`19`	Left main
`20`	Right main