# Aircraft Radio Navigation Variables<no value>
The tables below indicate the properties for the [Simulation Variables](../../simulation-variables/) that can be used to get and set properties related to the various radio navigation systems of an aircraft and Air Traffic Control. For information on the units listed for each variable, please see here: [Simulation Variable Units](../../simulation-variable-units/)

You can find a complete index of all available SimVars here: [SimVar Index](../../simulation-variables/#simvar-index)


### ADF

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="ADF-ACTIVE-FREQUENCY" />}}`ADF ACTIVE FREQUENCY` | ADF Index | {{< glossterm >}}adf{{< /glossterm >}} frequency. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | [Frequency ADF BCD32](../../simulation-variable-units/#Frequency-ADF-BCD32) |  {{< check/bad >}}  |
| {{< anchor id="ADF-AVAILABLE" />}}`ADF AVAILABLE` | ADF Index | `TRUE` if indexed ADF is available. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="ADF-CARD" />}}`ADF CARD` | N/A | {{< glossterm >}}adf{{< /glossterm >}} compass rose setting | Degrees |  {{< check/bad >}}  |
| {{< anchor id="ADF-DISTANCE" />}}`ADF DISTANCE` | N/A | The {{< glossterm >}}adf{{< /glossterm >}} signal distance. | Meters |  {{< check/bad >}}  |
| {{< anchor id="ADF-EXT-FREQUENCY" />}}<span class="legacy">`ADF EXT FREQUENCY`</span> | N/A | Deprecated, use [`ADF ACTIVE FREQUENCY`](#ADF-ACTIVE-FREQUENCY) | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="ADF-FREQUENCY" />}}<span class="legacy">`ADF FREQUENCY`</span> | N/A | Deprecated, use [`ADF ACTIVE FREQUENCY`](#ADF-ACTIVE-FREQUENCY) | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="ADF-IDENT" />}}`ADF IDENT` | N/A | {{< glossterm >}}icao_code{{< /glossterm >}} | String |  {{< check/bad >}}  |
| {{< anchor id="ADF-LATLONALT" />}}`ADF LATLONALT` | ADF Index | Returns the latitude, longitude and altitude of the station the radio equipment is currently tuned to, or zeros if the radio is not tuned to any ADF station. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | [Struct `struct`](../../simulation-variable-units/#latlonalt)<span></span>structure |  {{< check/bad >}}  |
| {{< anchor id="ADF-NAME" />}}`ADF NAME` | ADF Index | Descriptive name of the ADF. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String |  {{< check/bad >}}  |
| {{< anchor id="ADF-RADIAL" />}}`ADF RADIAL` | ADF Index | Current direction from {{< glossterm >}}ndb{{< /glossterm >}} station for the indexed ADF. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="ADF-RADIAL-MAG" />}}`ADF RADIAL MAG` | ADF Index | Returns the magnetic bearing to the currently tuned ADF transmitter for the indexed ADF. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="ADF-SIGNAL" />}}`ADF SIGNAL` | ADF Index | Signal strength of the indexed ADF. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Number |  {{< check/bad >}}  |
| {{< anchor id="ADF-SOUND" />}}`ADF SOUND` | ADF Index | {{< glossterm >}}adf{{< /glossterm >}} audio flag. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="ADF-STANDBY-AVAILABLE" />}}`ADF STANDBY AVAILABLE` | ADF Index | `TRUE` if {{< glossterm >}}adf{{< /glossterm >}} Standby is available, `FALSE` if otherwise. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="ADF-STANDBY-FREQUENCY" />}}`ADF STANDBY FREQUENCY` | ADF Index | {{< glossterm >}}adf{{< /glossterm >}} standby frequency. Index of 1 or 2, depending on how many were defined in the [Adf.N](../../../../content-configuration/cfg-files/systems.cfg/#Adf.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Hz |  {{< check/bad >}}  |
| {{< anchor id="ADF-VOLUME" />}}`ADF VOLUME` | N/A | Returns the volume of the {{< glossterm >}}adf{{< /glossterm >}} | {{< glossterm >}}percent_over_100{{< /glossterm >}} |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### ATC

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable     | Index| Description   | Units  |Settable     |
|---|---|---|---|:---:|
| {{< anchor id="ATC-AIRLINE" />}}`ATC AIRLINE` | N/A | The name of the Airline used by ATC, as a string with a maximum length of 50 characters.    | String | {{< check/good >}} |
| {{< anchor id="ATC-AIRPORT-IS-TOWERED" />}}`ATC AIRPORT IS TOWERED` | N/A | If the airport is controlled, this boolean is `TRUE`.     | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-ARRIVAL-AIRPORT-HAS-ATIS" />}}`ATC ARRIVAL AIRPORT HAS ATIS` | N/A | If the arrival airport has ATIS, this boolean is `TRUE`.  | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-ARRIVAL-AIRPORT-IS-TOWERED" />}}`ATC ARRIVAL AIRPORT IS TOWERED` | N/A | If the arrival airport is controlled, this boolean is `TRUE`.   | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-ASSIGNED-ALTITUDE" />}}`ATC ASSIGNED ALTITUDE` | N/A | The altitude assigned by the ATC. Returns -1 if no altitude is assigned.  | {{< glossterm >}}ft{{< /glossterm >}} | {{< check/bad >}} |
| {{< anchor id="ATC-CLEARED-IFR" />}}`ATC CLEARED IFR` | N/A | Returns whether or not the user has filed an IFR flightplan that has been cleared by the sim ATC  | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-CLEARED-LANDING" />}}`ATC CLEARED LANDING` | N/A | Whether the ATC has cleared the plane for landing.| Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-CLEARED-OVERFLIGHT-CTR" />}}`ATC CLEARED OVERFLIGHT CTR` | N/A | Whether the ATC has cleared the plane for overflight of CTR area.   | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-CLEARED-TAKEOFF" />}}`ATC CLEARED TAKEOFF` | N/A | Whether the ATC has cleared the plane for takeoff.| Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-CLEARED-TAXI" />}}`ATC CLEARED TAXI` | N/A | Whether the ATC has cleared the plane for taxi.   | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-CURRENT-WAYPOINT-ALTITUDE" />}}`ATC CURRENT WAYPOINT ALTITUDE` | N/A | Returns the target altitude for the current ATC flightplan waypoint.| Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-DEPARTURE-AIRPORT-IS-TOWERED" />}}`ATC DEPARTURE AIRPORT IS TOWERED` | N/A | If the departure airport is controlled, this boolean is `TRUE`. | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-DESIGNATED-GATE-ARRIVAL" />}}`ATC DESIGNATED GATE ARRIVAL` | N/A | The name of the gate assigned by the ATC for arrival. Returns "None" if no gate is assigned.| String | {{< check/bad >}} |
| {{< anchor id="ATC-DESIGNATED-GATE-DEPARTURE" />}}`ATC DESIGNATED GATE DEPARTURE` | N/A | The name of the gate assigned by the ATC for departure. Returns "None" if no gate is assigned.,   | String | {{< check/bad >}} |
| {{< anchor id="ATC-DESIGNATED-RUNWAY-LANDING" />}}`ATC DESIGNATED RUNWAY LANDING` | N/A | The name of the runway assigned by the ATC for landing. Returns "None" if no runway is assigned.  | String | {{< check/bad >}} |
| {{< anchor id="ATC-DESIGNATED-RUNWAY-TAKEOFF" />}}`ATC DESIGNATED RUNWAY TAKEOFF` | N/A | The name of the runway assigned by the ATC for takeoff. Returns "None" if no runway is assigned.  | String | {{< check/bad >}} |
| {{< anchor id="ATC-FIRST-VFR-ARRIVAL-PATTERN-WAYPOINT-NAME" />}}`ATC FIRST VFR ARRIVAL PATTERN WAYPOINT NAME` | N/A | The name of the first waypoint in VFR arrival procedure. Returns "None" if no waypoint is assigned.     | String | {{< check/bad >}} |
| {{< anchor id="ATC-FLIGHTPLAN-DIFF-ALT" />}}`ATC FLIGHTPLAN DIFF ALT` | N/A | Altitude between the position of the aircraft and his closest waypoints in the flightplan.  | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-FLIGHTPLAN-DIFF-DISTANCE" />}}`ATC FLIGHTPLAN DIFF DISTANCE` | N/A | Returns the lateral distance the user's plane is from the ATC flight plan track.| Meters | {{< check/bad >}} |
| {{< anchor id="ATC-FLIGHTPLAN-DIFF-HEADING" />}}`ATC FLIGHTPLAN DIFF HEADING` | N/A | Heading between the position of the aircraft and his closest waypoints in the flightplan.   | Degrees| {{< check/bad >}} |
| {{< anchor id="ATC-FP-ARRIVAL-TRAFFIC-PATTERN-IS-LEFTHANDED" />}}`ATC FP ARRIVAL TRAFFIC PATTERN IS LEFTHANDED` | N/A | If `TRUE` (1) then the traffic pattern is left handed at arrival, otherwise it is right handed.     | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-FP-DEPARTURE-TRAFFIC-PATTERN-IS-LEFTHANDED" />}}`ATC FP DEPARTURE TRAFFIC PATTERN IS LEFTHANDED` | N/A | If `TRUE` (1) then the traffic pattern is left handed at departure, otherwise it is right handed.   | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-FLIGHT-NUMBER" />}}`ATC FLIGHT NUMBER` | N/A | Flight Number used by ATC, as a string with a maximum number of 6 characters.   | String | {{< check/good >}} |
| {{< anchor id="ATC-FUTURE-AGENT-DISTANCE" />}}`ATC FUTURE AGENT DISTANCE` | N/A | Distance to future agent ({{< glossterm >}}nm{{< /glossterm >}}).    | Number | {{< check/bad >}} |
| {{< anchor id="ATC-FUTURE-AGENT-FREQUENCY" />}}`ATC FUTURE AGENT FREQUENCY` | N/A | Frequency of future agent.| Number | {{< check/bad >}} |
| {{< anchor id="ATC-FUTURE-AGENT-NAME" />}}`ATC FUTURE AGENT NAME` | N/A | Name of future agent.     | String | {{< check/bad >}} |
| {{< anchor id="ATC-FUTURE-AGENT-TYPE" />}}`ATC FUTURE AGENT TYPE` | N/A | Type of future agent.     | Number | {{< check/bad >}} |
| {{< anchor id="ATC-HEAVY" />}}`ATC HEAVY` | N/A | Is this aircraft recognized by ATC as heavy.| Bool   | {{< check/good >}} |
| {{< anchor id="ATC-ID" />}}`ATC ID` | N/A | ID used by ATC, as a string with a maximum number of 10 characters. | String | {{< check/good >}} |
| {{< anchor id="ATC-IFR-FP-TO-REQUEST" />}}`ATC IFR FP TO REQUEST` | N/A | Returns `TRUE` if the user has a valid IFR flight plan they can as for clearance for with ATC at the airport they are currently at.     | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-MISSION-FP-IFR" />}}`ATC MISSION FP IFR` | N/A | Returns `TRUE` if the mission requires an IFR flight plan.| Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-MODEL" />}}`ATC MODEL` | N/A | Model used by ATC, as a string with a maximum number of 128 characters.   | String | {{< check/bad >}} |
| {{< anchor id="ATC-NAME" />}}`ATC NAME` | N/A | Aircraft name used by ATC, as a string with a maximum number of 50 characters.  | String | {{< check/good >}} |
| {{< anchor id="ATC-NEXT-WAYPOINT-ALTITUDE" />}}`ATC NEXT WAYPOINT ALTITUDE` | N/A | This will indicate the altitude of the next waypoint of the flightpath.   | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-NEXT-WAYPOINT-NAME" />}}`ATC NEXT WAYPOINT NAME` | N/A | The name of the next waypoint assigned by the ATC. Returns "None" if no waypoint is assigned.     | String | {{< check/bad >}} |
| {{< anchor id="ATC-ON-PARKING-SPOT" />}}`ATC ON PARKING SPOT` | N/A | Is ATC aircraft on parking spot.| Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-OVERFLYING-AIRPORT-UNANNOUNCED" />}}`ATC OVERFLYING AIRPORT UNANNOUNCED` | N/A | Is ATC aircraft overflying an airport without announcing themselves.| Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-PREVIOUS-WAYPOINT-ALTITUDE" />}}`ATC PREVIOUS WAYPOINT ALTITUDE` | N/A | Returns the target altitude for the previous ATC flightplan waypoint.     | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-AIRPORT-NAME" />}}`ATC RUNWAY AIRPORT NAME` | N/A | The name of the airport of the runway assigned by the ATC. Returns "" if no runway is assigned.   | String | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-DISTANCE" />}}`ATC RUNWAY DISTANCE` | N/A | This float represents the distance between the player's plane and the center of the runway selected by the ATC.     | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-END-DISTANCE" />}}`ATC RUNWAY END DISTANCE` | N/A | This is a float corresponding to the horizontal distance between the player's plane and the end of the runway selected by the ATC.    | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-HEADING-DEGREES-TRUE" />}}`ATC RUNWAY HEADING DEGREES TRUE` | N/A | This float represents the true heading of the runway selected by the ATC. | Degrees| {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-LENGTH" />}}`ATC RUNWAY LENGTH` | N/A | The length of the runway assigned by the ATC. Returns -1 if no runway is assigned.    | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-RELATIVE-POSITION-X" />}}`ATC RUNWAY RELATIVE POSITION X` | N/A | This is a float corresponding to the player's main gear relative X (transverse) position on the runway selected by the ATC.     | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-RELATIVE-POSITION-Y" />}}`ATC RUNWAY RELATIVE POSITION Y` | N/A | This is a float corresponding to the player's main gear relative Y (height) position on the runway selected by the ATC.   | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-RELATIVE-POSITION-Z" />}}`ATC RUNWAY RELATIVE POSITION Z` | N/A | This is a float corresponding to the player's main gear relative Z (longitudinal) position on the runway selected by the ATC.   | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-SELECTED" />}}`ATC RUNWAY SELECTED` | N/A | This is a boolean corresponding to whether or not the ATC has pre-selected a runway for the player's plane. If this is `FALSE`, every other `ATC RUNWAY *` SimVar will return default values. | Bool   | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-START-DISTANCE" />}}`ATC RUNWAY START DISTANCE` | N/A | This is a float corresponding to the horizontal distance between the player's plane and the start of the runway selected by the ATC.  | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-TDPOINT-RELATIVE-POSITION-X" />}}`ATC RUNWAY TDPOINT RELATIVE POSITION X` | N/A | This float represents the player's main gear relative X (transverse) position according to the aiming point of the runway selected by the ATC.    | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-TDPOINT-RELATIVE-POSITION-Y" />}}`ATC RUNWAY TDPOINT RELATIVE POSITION Y` | N/A | This float represents the player's main gear relative Y (height) position according to the aiming point of the runway selected by the ATC.  | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-TDPOINT-RELATIVE-POSITION-Z" />}}`ATC RUNWAY TDPOINT RELATIVE POSITION Z` | N/A | This float represents the player's main relative Z (longitudinal) position according to the aiming point of the runway selected by the ATC. | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-RUNWAY-WIDTH" />}}`ATC RUNWAY WIDTH` | N/A | The width of the runway assigned by the ATC. Returns -1 if no runway is assigned.     | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-SUGGESTED-MIN-RWY-LANDING" />}}`ATC SUGGESTED MIN RWY LANDING` | N/A | Suggested minimum runway length for landing. Used by ATC.     | Feet   | {{< check/bad >}} |
| {{< anchor id="ATC-SUGGESTED-MIN-RWY-TAKEOFF" />}}`ATC SUGGESTED MIN RWY TAKEOFF` | N/A | Suggested minimum runway length for takeoff. Used by ATC.     | Feet   | {{< check/bad >}} |
| {{< anchor id="ATC-TAXIPATH-DISTANCE" />}}`ATC TAXIPATH DISTANCE` | N/A | Returns the lateral distance the user's plane is from the path of the currently issued ATC taxi instructions. | Meters | {{< check/bad >}} |
| {{< anchor id="ATC-TYPE" />}}`ATC TYPE` | N/A | Type used by ATC, as a string with a maximum number of 128 characters.    | String | {{< check/bad >}} |
| {{< anchor id="ATC-WAYPOINTS-HIGHEST-ALTITUDE" />}}`ATC WAYPOINTS HIGHEST ALTITUDE` | N/A | This will indicate the highest altitude from all of the waypoints in the flightpath.  | Meters | {{< check/bad >}} |

{{< /table-wrapper >}}


### COM

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="COM1-STORED-FREQUENCY" />}}`COM1 STORED FREQUENCY` | N/A | The stored COM 1/2/3 frequency value. The number of COM will depend on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="COM2-STORED-FREQUENCY" />}}`COM2 STORED FREQUENCY` | N/A | The stored COM 1/2/3 frequency value. The number of COM will depend on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="COM3-STORED-FREQUENCY" />}}`COM3 STORED FREQUENCY` | N/A | The stored COM 1/2/3 frequency value. The number of COM will depend on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="COM-ACTIVE-BEARING" />}}`COM ACTIVE BEARING` | Com Index | Gives the bearing (in degrees) of the active COM station (airport) or a value less than 0 if the station does not belong to an airport. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="COM-ACTIVE-DISTANCE" />}}`COM ACTIVE DISTANCE` | Com Index | Gives the distance (in meters) to the active COM station (airport) or a value less than -180° if the station does not belong to an airport. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Meters |  {{< check/bad >}}  |
| {{< anchor id="COM-ACTIVE-FREQUENCY" />}}`COM ACTIVE FREQUENCY` | Com Index | Com frequency. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="COM-ACTIVE-FREQ-IDENT" />}}`COM ACTIVE FREQ IDENT` | Com Index | The identity of the station that is tuned on the indexed active COM radio. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String |  {{< check/bad >}}  |
| {{< anchor id="COM-ACTIVE-FREQ-TYPE" />}}`COM ACTIVE FREQ TYPE` | Com Index | The type of COM frequency for the active indexed COM system. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String:<span></span>{{< params/smallfont >}}"ATIS" - Atis<span></span>"UNI" - Unicom<span></span>"CTAF" - CTAF<span></span>"GND" - Ground<span></span>"TWR" - Tower<span></span>"CLR" - Clearance<span></span>Delivery<span></span>"APPR" - Approach<span></span>"DEP" - Departure<span></span>"FSS" - FSS<span></span>"AWS" - AWOS{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="COM-ACTIVE-LATLONALT" />}}`COM ACTIVE LATLONALT` | Com Index | This will return the latitude, longitude and altitude corresponding to the indexed COM station associated with the active COM frequency. If the station is not associated with an airport, then the lat/lon/alt values returned will be `-15943°, 80°, -10000` (this means that you can simply check that the altitude value is greater than 0 to assure the validity of the returned struct).<span></span>Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Struct:<span></span>[Struct `struct`](../../simulation-variable-units/#latlonalt) |  {{< check/bad >}}  |
| {{< anchor id="COM-AVAILABLE" />}}`COM AVAILABLE` | Com Index | `TRUE` if COM1, COM2 or COM3 is available. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="COM-LATLONALT" />}}`COM LATLONALT` | Com Index | *Not currently used in the simulation.* | Struct:<span></span>[Struct `struct`](../../simulation-variable-units/#latlonalt) |  {{< check/bad >}}  |
| {{< anchor id="COM-RECEIVE" />}}`COM RECEIVE` | Com Index | Whether or not the plane is receiving on the indexed com channel or not. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="COM-RECEIVE-ALL" />}}`COM RECEIVE ALL` | N/A | Toggles all COM radios to receive on | Bool |  {{< check/bad >}}  |
| {{< anchor id="COM-RECEIVE-EX1" />}}`COM RECEIVE EX1` | Com Index | Whether or not the plane is receiving on the indexed com channel. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="COM-SPACING-MODE" />}}`COM SPACING MODE` | Com Index | The COM radio frequency step. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Enum:<span></span>0 = 25kHz<span></span>1 = 8.33kHz |  {{< check/bad >}}  |
| {{< anchor id="COM-STANDBY-FREQUENCY" />}}`COM STANDBY FREQUENCY` | Com Index | Com standby frequency. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Frequency [Frequency BCD16](../../simulation-variable-units/#Frequency-BCD16) |  {{< check/bad >}}  |
| {{< anchor id="COM-STANDBY-FREQ-IDENT" />}}`COM STANDBY FREQ IDENT` | Com Index | The identity of the station that is tuned on the indexed standby COM radio. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String |  {{< check/bad >}}  |
| {{< anchor id="COM-STANDBY-FREQ-TYPE" />}}`COM STANDBY FREQ TYPE` | Com Index | The type of COM frequency for the standby indexed COM system. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String:<span></span>{{< params/smallfont >}}"ATIS" - Atis<span></span>"UNI" - Unicom<span></span>"CTAF" - CTAF<span></span>"GND" - Ground<span></span>"TWR" - Tower<span></span>"CLR" - Clearance<span></span>Delivery<span></span>"APPR" - Approach<span></span>"DEP" - Departure<span></span>"FSS" - FSS<span></span>"AWS" - AWOS>{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="COM-STATUS" />}}`COM STATUS` | Com Index | Radio status flag for the indexed com channel. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Enum:<span></span>{{< params/smallfont >}}-1 = Invalid<span></span>0 = OK<span></span>1 = Does not exist<span></span>2 = No electricity<span></span>3 = Failed{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="COM-TEST" />}}`COM TEST` | Com Index | Will return `TRUE` if the COM system is working, `FALSE` otherwise. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="COM-TRANSMIT" />}}`COM TRANSMIT` | Com Index | Audio panel transmit status of the indexed COM. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="COM-VOLUME" />}}`COM VOLUME` | Com Index | The volume of the indexed COM Radio. Index of 1-3, depending on how many were defined in the [Com.N](../../../../content-configuration/cfg-files/systems.cfg/#Com.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Percent |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### FLARM

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="FLARM-AVAILABLE" />}}`FLARM AVAILABLE` | N/A | Whether the FLARM is available (`TRUE`, 1) or not (`FALSE`, 0). | Bool |  {{< check/good >}}  |
| {{< anchor id="FLARM-THREAT-BEARING" />}}`FLARM THREAT BEARING` | N/A | The bearing of the FLARM threat aircraft, relative to track. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="FLARM-THREAT-DATA" />}}`FLARM THREAT DATA` | N/A | The FLARM threat aircraft data structure, which contains data about the perceived threat, returned as a struct. Struct member variables are as follows:<span></span>{{< params/smallfont >}}`id` (U64): the network ID of the intruding plane so that they are remembered in order to compute their trajectory.<span></span>`bearing` (FLOAT64): The threat bearing, in degrees (this is bearing from track axis and not bearing from the airplane axis).<span></span>`heading` (FLOAT64): The threat heading.<span></span>`distance` (FLOAT64): The distance between the aircraft and the threat, in meters.<span></span>`verticalBearing` (FLOAT64): The vertical bearing between the aircraft and the threat, in degrees.<span></span>`relativeAltitude` (FLOAT64): The relative altitude of the threat to the aircraft, in meters.<span></span>`timeToCollision` (FLOAT64): The estimated time to a collision, in seconds.{{< /params/smallfont >}} | Struct |  {{< check/bad >}}  |
| {{< anchor id="FLARM-THREAT-DISTANCE" />}}`FLARM THREAT DISTANCE` | N/A | The distance to the FLARM threat object. | Meters |  {{< check/bad >}}  |
| {{< anchor id="FLARM-THREAT-HEADING" />}}`FLARM THREAT HEADING` | N/A | The heading to the FLARM threat object. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="FLARM-THREAT-RELATIVE-ALTITUDE" />}}`FLARM THREAT RELATIVE ALTITUDE` | N/A | The relative altitude of the threat object. | Meters |  {{< check/bad >}}  |
| {{< anchor id="FLARM-THREAT-TIME-TO-COLLISION" />}}`FLARM THREAT TIME TO COLLISION` | N/A | The estimated time to a collision. | Seconds |  {{< check/bad >}}  |
| {{< anchor id="FLARM-THREAT-VERTICAL-BEARING" />}}`FLARM THREAT VERTICAL BEARING` | N/A | The vertical bearing towards the threat. | Degrees |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### GPS

When using these SimVars, it is worth noting that to correctly set those that can be set, you should first use the SimVar [`GPS OVERRIDEN`](#GPS-OVERRIDEN) and set it to `TRUE`. If you don't set this SimVar, then any changes that are made to the other GPS variables will be overriden by the simulation GPS system moments after you set them.


{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="GPS-APPROACH-AIRPORT-ID" />}}`GPS APPROACH AIRPORT ID` | N/A | ID of airport. | String |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-APPROACH-ID" />}}`GPS APPROACH APPROACH ID` | N/A | ID of approach. | String |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-APPROACH-INDEX" />}}`GPS APPROACH APPROACH INDEX` | N/A | Index of approach for given airport. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-APPROACH-TYPE" />}}`GPS APPROACH APPROACH TYPE` | N/A | Approach type. | Enum:<span></span>{{< params/smallfont >}}0 = None<span></span>1 = {{< glossterm >}}gps{{< /glossterm >}}<span></span>2 = {{< glossterm >}}vor{{< /glossterm >}}<span></span>3 = {{< glossterm >}}ndb{{< /glossterm >}}<span></span>4 = {{< glossterm >}}ils{{< /glossterm >}}<span></span>5 = Localizer<span></span>6 = {{< glossterm >}}sdf{{< /glossterm >}}<span></span>7 = {{< glossterm >}}lda{{< /glossterm >}}<span></span>8 = {{< glossterm >}}vor{{< /glossterm >}}/ {{< glossterm >}}dme{{< /glossterm >}}<span></span>9 = {{< glossterm >}}ndb{{< /glossterm >}}/ {{< glossterm >}}dme{{< /glossterm >}}<span></span>10 = {{< glossterm >}}rnav{{< /glossterm >}}<span></span>11 = Backcourse{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-IS-FINAL" />}}`GPS APPROACH IS FINAL` | N/A | Is approach transition final approach segment. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-IS-MISSED" />}}`GPS APPROACH IS MISSED` | N/A | Is approach segment missed approach segment. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-IS-WP-RUNWAY" />}}`GPS APPROACH IS WP RUNWAY` | N/A | Waypoint is the runway. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-MODE" />}}`GPS APPROACH MODE` | N/A | Sub mode within approach mode. | Enum:<span></span>{{< params/smallfont >}}0 = None<span></span>1 = Transition<span></span>2 = Final<span></span>3 = Missed{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-SEGMENT-TYPE" />}}`GPS APPROACH SEGMENT TYPE` | N/A | Segment type within approach. | Enum:<span></span>{{< params/smallfont >}}0 = Line<span></span>1 = Arc clockwise<span></span>2 = Arc counter-clockwise{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-TIMEZONE-DEVIATION" />}}`GPS APPROACH TIMEZONE DEVIATION` | N/A | Deviation of local time from GMT. | Seconds |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-TRANSITION-ID" />}}`GPS APPROACH TRANSITION ID` | N/A | ID of approach transition. | String |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-TRANSITION-INDEX" />}}`GPS APPROACH TRANSITION INDEX` | N/A | Index of approach transition. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-WP-COUNT" />}}`GPS APPROACH WP COUNT` | N/A | Number of waypoints. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-WP-INDEX" />}}`GPS APPROACH WP INDEX` | N/A | Index of current waypoint. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-APPROACH-WP-TYPE" />}}`GPS APPROACH WP TYPE` | N/A | Waypoint type within approach mode. | Enum:<span></span>{{< params/smallfont >}}0 = None<span></span>1 = Fix<span></span>2 = Procedure turn left<span></span>3 = Procedure turn right<span></span>4 = Dme arc left<span></span>5 = Dme arc right<span></span>6 = Holding left<span></span>7 = Holding right<span></span>8 = Distance<span></span>9 = Altitude<span></span>10 = Manual sequence<span></span>11 = Vector to final{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="GPS-CDI-NEEDLE" />}}`GPS CDI NEEDLE` | N/A | The course deviation of the needle for a CDI instrument. The SimVar displays the deviation from -127 to +127. It returns a value if a flight plan is set (otherwise it will return 0) even if the autopilot isn't on GPS mode. Scaling can also be set through the [`GPS CDI SCALING`](#GPS-CDI-SCALING) simvar. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-CDI-SCALING" />}}`GPS CDI SCALING` | N/A | The full scale deflection of the CDI due to GPS cross-track error, in meters. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-COURSE-TO-STEER" />}}`GPS COURSE TO STEER` | N/A | Suggested heading to steer (for autopilot). | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-DRIVES-NAV1" />}}`GPS DRIVES NAV1` | N/A | GPS is driving Nav 1 indicator. Note this setting will also affect the SimVars [`HSI STATION IDENT`](#HSI-STATION-IDENT) and [`HSI BEARING`](#HSI-BEARING). | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-ETA" />}}`GPS ETA` | N/A | Estimated time of arrival at destination. | Seconds |  {{< check/bad >}}  |
| {{< anchor id="GPS-ETE" />}}`GPS ETE` | N/A | Estimated time en route to destination. | Seconds |  {{< check/bad >}}  |
| {{< anchor id="GPS-FLIGHTPLAN-TOTAL-DISTANCE" />}}`GPS FLIGHTPLAN TOTAL DISTANCE` | N/A | This is the complete flightplan length from start to end. Essentially the cumulative length of all the flight plan legs added together. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-FLIGHT-PLAN-WP-COUNT" />}}`GPS FLIGHT PLAN WP COUNT` | N/A | Number of waypoints. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-FLIGHT-PLAN-WP-INDEX" />}}`GPS FLIGHT PLAN WP INDEX` | N/A | Index of waypoint. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-GROUND-MAGNETIC-TRACK" />}}`GPS GROUND MAGNETIC TRACK` | N/A | Current magnetic ground track. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-GROUND-SPEED" />}}`GPS GROUND SPEED` | N/A | Current ground speed. | Meters per second |  {{< check/bad >}}  |
| {{< anchor id="GPS-GROUND-TRUE-HEADING" />}}`GPS GROUND TRUE HEADING` | N/A | Current true heading. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-GROUND-TRUE-TRACK" />}}`GPS GROUND TRUE TRACK` | N/A | Current true ground track. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-GSI-SCALING" />}}`GPS GSI SCALING` | N/A | The full scale deflection of the vertical GSI due to GPS glidepath deviation, in meters. | Meters |  {{< check/good >}}  |
| {{< anchor id="GPS-GSI-NEEDLE" />}}`GPS GSI NEEDLE` | N/A | The GPS glideslope needle deflection (+/- 127). | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-HAS-GLIDEPATH" />}}`GPS HAS GLIDEPATH` | N/A | Whether or not the GPS system has a presently available glidepath for guidance. Only applicable with [`GPS OVERRIDDEN`](#GPS-OVERRIDDEN). When `TRUE`, [`HSI GSI NEEDLE VALID`](#HSI-GSI-NEEDLE-VALID) will also be `TRUE`. | Bool |  {{< check/good >}}  |
| {{< anchor id="GPS-HSI-NEEDLE" />}}`GPS HSI NEEDLE` | N/A | The glide deviation of the needle for a CDI instrument. The simvar displays the deviation from -127 to +127. It returns a value if a flight plan is set (otherwise it will return 0) even if the autopilot isn't on GPS mode. Scaling can also be set through the [`GPS CDI SCALING`](#GPS-CDI-SCALING) simvar. | Number |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-ACTIVE-FLIGHT-PLAN" />}}`GPS IS ACTIVE FLIGHT PLAN` | N/A | Flight plan mode active. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-ACTIVE-WAY-POINT" />}}`GPS IS ACTIVE WAY POINT` | N/A | Waypoint mode active. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-ACTIVE-WP-LOCKED" />}}`GPS IS ACTIVE WP LOCKED` | N/A | Is switching to next waypoint locked. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-APPROACH-ACTIVE" />}}`GPS IS APPROACH ACTIVE` | N/A | Is approach mode active. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-APPROACH-LOADED" />}}`GPS IS APPROACH LOADED` | N/A | Is approach loaded. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-ARRIVED" />}}`GPS IS ARRIVED` | N/A | Is flight plan destination reached. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-IS-DIRECTTO-FLIGHTPLAN" />}}`GPS IS DIRECTTO FLIGHTPLAN` | N/A | Is Direct To Waypoint mode active. | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-MAGVAR" />}}`GPS MAGVAR` | N/A | Current GPS magnetic variation. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-OBS-ACTIVE" />}}`GPS OBS ACTIVE` | N/A | Whether or not the OBS mode is currently active (disable the automatic sequencing of waypoints in GPS flight plan). | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-OBS-VALUE" />}}`GPS OBS VALUE` | N/A | This is the currently selected OBS course in degrees, from 0 to 360. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-OVERRIDDEN" />}}`GPS OVERRIDDEN` | N/A | When it is active, all sim GPS system updates are suspended. This must be set to `TRUE` to be able to correctly set to any other GPS SimVar. | Bool |  {{< check/good >}}  |
| {{< anchor id="GPS-POSITION-ALT" />}}`GPS POSITION ALT` | N/A | Current GPS altitude. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-POSITION-LAT" />}}`GPS POSITION LAT` | N/A | Current GPS latitude. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-POSITION-LON" />}}`GPS POSITION LON` | N/A | Current GPS longitude. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-TARGET-ALTITUDE" />}}`GPS TARGET ALTITUDE` | N/A | Altitude of GPS target. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-TARGET-DISTANCE" />}}`GPS TARGET DISTANCE` | N/A | Distance to target. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-VERTICAL-ANGLE" />}}`GPS VERTICAL ANGLE` | N/A | Glidepath in degrees. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-VERTICAL-ANGLE-ERROR" />}}`GPS VERTICAL ANGLE ERROR` | N/A | Vertical error in degrees from GlidePath. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-VERTICAL-ERROR" />}}`GPS VERTICAL ERROR` | N/A | Vertical deviation in meters from GlidePath. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-BEARING" />}}`GPS WP BEARING` | N/A | Magnetic bearing to waypoint. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-CROSS-TRK" />}}`GPS WP CROSS TRK` | N/A | Cross track distance. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-DESIRED-TRACK" />}}`GPS WP DESIRED TRACK` | N/A | The required heading (magnetic) from the previous waypoint to the next waypoint. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-DISTANCE" />}}`GPS WP DISTANCE` | N/A | Distance to waypoint. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-ETA" />}}`GPS WP ETA` | N/A | Estimated time of arrival at waypoint. | Seconds |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-ETE" />}}`GPS WP ETE` | N/A | Estimated time en route to waypoint. | Seconds |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-NEXT-ALT" />}}`GPS WP NEXT ALT` | N/A | Altitude of next waypoint. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-NEXT-ID" />}}`GPS WP NEXT ID` | N/A | ID of next GPS waypoint. | String |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-NEXT-LAT" />}}`GPS WP NEXT LAT` | N/A | Latitude of next waypoint. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-NEXT-LON" />}}`GPS WP NEXT LON` | N/A | Longitude of next waypoint. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-PREV-ALT" />}}`GPS WP PREV ALT` | N/A | Altitude of previous waypoint. | Meters |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-PREV-ID" />}}`GPS WP PREV ID` | N/A | ID of previous GPS waypoint. | String |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-PREV-LAT" />}}`GPS WP PREV LAT` | N/A | Latitude of previous waypoint. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-PREV-LON" />}}`GPS WP PREV LON` | N/A | Longitude of previous waypoint. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-PREV-VALID" />}}`GPS WP PREV VALID` | N/A | Is previous waypoint valid (i.e. current waypoint is not the first waypoint). | Bool |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-TRACK-ANGLE-ERROR" />}}`GPS WP TRACK ANGLE ERROR` | N/A | Tracking angle error to waypoint. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-TRUE-BEARING" />}}`GPS WP TRUE BEARING` | N/A | True bearing to waypoint. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-TRUE-REQ-HDG" />}}`GPS WP TRUE REQ HDG` | N/A | Required true heading to waypoint. | Radians |  {{< check/bad >}}  |
| {{< anchor id="GPS-WP-VERTICAL-SPEED" />}}`GPS WP VERTICAL SPEED` | N/A | Vertical speed to waypoint. | Meters per second |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### HSI

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="HSI-BEARING" />}}`HSI BEARING` | N/A | If the [`GPS DRIVES NAV1`](#GPS-DRIVES-NAV1) variable is `TRUE` and the [`HSI BEARING VALID`](#HSI-BEARING-VALID) variable is `TRUE`, this variable contains the HSI needle bearing. If the [`GPS DRIVES NAV1`](#GPS-DRIVES-NAV1) variable is `FALSE` and the [`HSI BEARING VALID`](#HSI-BEARING-VALID) variable is `TRUE`, this variable contains the ADF1 frequency. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="HSI-BEARING-VALID" />}}`HSI BEARING VALID` | N/A | This will return `TRUE` if the [`HSI BEARING`](#HSI-BEARING) variable contains valid data. | Bool |  {{< check/bad >}}  |
| {{< anchor id="HSI-CDI-NEEDLE" />}}`HSI CDI NEEDLE` | N/A | Needle deflection (+/- 127). | Number |  {{< check/bad >}}  |
| {{< anchor id="HSI-CDI-NEEDLE-VALID" />}}`HSI CDI NEEDLE VALID` | N/A | Signal valid. | Bool |  {{< check/bad >}}  |
| {{< anchor id="HSI-DISTANCE" />}}`HSI DISTANCE` | N/A | DME/GPS distance. | Nautical miles |  {{< check/bad >}}  |
| {{< anchor id="HSI-GSI-NEEDLE" />}}`HSI GSI NEEDLE` | N/A | Needle deflection (+/- 119). | Number |  {{< check/bad >}}  |
| {{< anchor id="HSI-GSI-NEEDLE-VALID" />}}`HSI GSI NEEDLE VALID` | N/A | Signal valid. | Bool |  {{< check/bad >}}  |
| {{< anchor id="HSI-HAS-LOCALIZER" />}}`HSI HAS LOCALIZER` | N/A | Station is a localizer. | Bool |  {{< check/bad >}}  |
| {{< anchor id="HSI-SPEED" />}}`HSI SPEED` | N/A | DME/GPS speed. | Knots |  {{< check/bad >}}  |
| {{< anchor id="HSI-STATION-IDENT" />}}`HSI STATION IDENT` | N/A | Returns the ident of the the next GPS waypoint, if [`GPS DRIVES NAV1`](#GPS-DRIVES-NAV1) is `TRUE`. If `GPS DRIVES NAV1` is `FALSE`, it returns the identity of the station that is tuned on nav radio 1. | String |  {{< check/bad >}}  |
| {{< anchor id="HSI-TF-FLAGS" />}}`HSI TF FLAGS` | N/A | Nav TO/FROM flag. | Enum:<span></span>{{< params/smallfont >}}0 = Off<span></span>1 = TO<span></span>2 = FROM{{< /params/smallfont >}} |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### MARKERS

These SimVars are only valid if a [Marker.N](../../../../content-configuration/cfg-files/systems.cfg/#Marker.N) has been defined in the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). Note that more than 1 marker is not currently supported by the simulation.


{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="INNER-MARKER" />}}`INNER MARKER` | N/A | Inner marker state. | Bool |  {{< check/good >}}  |
| {{< anchor id="INNER-MARKER-LATLONALT" />}}`INNER MARKER LATLONALT` | N/A | Returns the latitude, longitude and altitude of the inner marker of an approach to a runway, if the aircraft is within the required proximity, otherwise it will return zeros. | [Struct `struct`](../../simulation-variable-units/#latlonalt)<span></span>structure |  {{< check/bad >}}  |
| {{< anchor id="MARKER-AVAILABLE" />}}`MARKER AVAILABLE` | N/A | `TRUE` if Marker is available. | Bool |  {{< check/bad >}}  |
| {{< anchor id="MARKER-BEACON-SENSITIVITY-HIGH" />}}`MARKER BEACON SENSITIVITY HIGH` | N/A | Whether or not the Marker Beacon is in High Sensitivity mode. | Bool |  {{< check/bad >}}  |
| {{< anchor id="MARKER-BEACON-STATE" />}}`MARKER BEACON STATE` | N/A | Marker beacon state. | Enum:<span></span>{{< params/smallfont >}}0 = None<span></span>1 = Outer<span></span>2 = Middle<span></span>3 = Inner{{< /params/smallfont >}} |  {{< check/good >}}  |
| {{< anchor id="MARKER-BEACON-TEST-MUTE" />}}`MARKER BEACON TEST MUTE` | N/A | Whether or not the Marker Beacon is in Test/Mute mode. | Bool |  {{< check/bad >}}  |
| {{< anchor id="MARKER-SOUND" />}}`MARKER SOUND` | N/A | Marker audio flag. | Bool |  {{< check/bad >}}  |
| {{< anchor id="MIDDLE-MARKER" />}}`MIDDLE MARKER` | N/A | Middle marker state. | Bool |  {{< check/good >}}  |
| {{< anchor id="MIDDLE-MARKER-LATLONALT" />}}`MIDDLE MARKER LATLONALT` | N/A | Returns the latitude, longitude and altitude of the middle marker. | [Struct `struct`](../../simulation-variable-units/#latlonalt)<span></span>structure |  {{< check/bad >}}  |
| {{< anchor id="OUTER-MARKER" />}}`OUTER MARKER` | N/A | Outer marker state. | Bool |  {{< check/good >}}  |
| {{< anchor id="OUTER-MARKER-LATLONALT" />}}`OUTER MARKER LATLONALT` | N/A | Returns the latitude, longitude and altitude of the outer marker. | [Struct `struct`](../../simulation-variable-units/#latlonalt)<span></span>structure |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### NAV

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="NAV-ACTIVE-FREQUENCY" />}}`NAV ACTIVE FREQUENCY` | Navigation Index | Nav active frequency. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | MHz |  {{< check/bad >}}  |
| {{< anchor id="NAV-AVAILABLE" />}}`NAV AVAILABLE` | Navigation Index | Flag if indexed Nav equipped on aircraft. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-BACK-COURSE-FLAGS" />}}`NAV BACK COURSE FLAGS` | Navigation Index | Returns the listed bit flags. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Flags:<span></span>{{< params/smallfont >}}BIT3: station active<span></span>BIT2: on course<span></span>BIT1: localizer tuned in<span></span>BIT0: back course available{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="NAV-CDI" />}}`NAV CDI` | Navigation Index | CDI needle deflection (+/- 127). Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Number |  {{< check/bad >}}  |
| {{< anchor id="NAV-CLOSE-DME" />}}`NAV CLOSE DME` | Navigation Index | Closest {{< glossterm >}}dme{{< /glossterm >}} distance. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/).<span></span>Note that this SimVar will only work if the [`NAV1 CLOSE FREQ SET`](../../../key-events/aircraft-radio-navigation-events/#NAV1_CLOSE_FREQ_SET) key event has been set to 1 (`TRUE`). | Nautical miles |  {{< check/bad >}}  |
| {{< anchor id="NAV-CLOSE-FREQUENCY" />}}`NAV CLOSE FREQUENCY` | Navigation Index | Closest localizer course frequency. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/).<span></span>Note that this SimVar will only work if the [`NAV1 CLOSE FREQ SET`](../../../key-events/aircraft-radio-navigation-events/#NAV1_CLOSE_FREQ_SET) key event has been set to 1 (`TRUE`). | Hz |  {{< check/bad >}}  |
| {{< anchor id="NAV-CLOSE-IDENT" />}}`NAV CLOSE IDENT` | Navigation Index | Closest ICAO code identity. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/).<span></span>Note that this SimVar will only work if the [`NAV1 CLOSE FREQ SET`](../../../key-events/aircraft-radio-navigation-events/#NAV1_CLOSE_FREQ_SET) key event has been set to 1 (`TRUE`). | String |  {{< check/bad >}}  |
| {{< anchor id="NAV-CLOSE-LOCALIZER" />}}`NAV CLOSE LOCALIZER` | Navigation Index | Closest localizer course heading. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/).<span></span>Note that this SimVar will only work if the [`NAV1 CLOSE FREQ SET`](../../../key-events/aircraft-radio-navigation-events/#NAV1_CLOSE_FREQ_SET) key event has been set to 1 (`TRUE`). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-CLOSE-NAME" />}}`NAV CLOSE NAME` | Navigation Index | Descriptive name. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/).<span></span>Note that this SimVar will only work if the [`NAV1 CLOSE FREQ SET`](../../../key-events/aircraft-radio-navigation-events/#NAV1_CLOSE_FREQ_SET) key event has been set to 1 (`TRUE`). | String |  {{< check/bad >}}  |
| {{< anchor id="NAV-CODES" />}}`NAV CODES` | Navigation Index | Returns bit flags with the listed meaning. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Flags:<span></span>{{< params/smallfont >}}BIT7: VOR Localizer<span></span>BIT6: glideslope available<span></span>BIT5: no localizer backcourse<span></span>BIT4: DME transmitter at glide slope transmitter<span></span>BIT3: no nav signal available<span></span>BIT2: voice available<span></span>BIT1: TACAN available<span></span>BIT0: DME available{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="NAV-DME" />}}`NAV DME` | N/A | {{< glossterm >}}dme{{< /glossterm >}} distance. | Nautical miles |  {{< check/bad >}}  |
| {{< anchor id="NAV-DMESPEED" />}}`NAV DMESPEED` | N/A | {{< glossterm >}}dme{{< /glossterm >}} speed. | Knots |  {{< check/bad >}}  |
| {{< anchor id="NAV-DME-LATLONALT" />}}`NAV DME LATLONALT` | N/A | Returns the {{< glossterm >}}dme{{< /glossterm >}} station. | [Struct `struct`](../../simulation-variable-units/#latlonalt) structure |  {{< check/bad >}}  |
| {{< anchor id="NAV-FREQUENCY" />}}`NAV FREQUENCY` | N/A | Localizer course frequency. | Hz |  {{< check/bad >}}  |
| {{< anchor id="NAV-GLIDE-SLOPE" />}}`NAV GLIDE SLOPE` | N/A | The glide slope gradient. The value returned is an integer value formed as follows:<span></span>`sin(slope) 65536 2`<span></span>So, for example, a glide slope of 2.7º would return a value of 6174. TO get the value in degrees, then use [`NAV RAW GLIDE SLOPE`](#NAV-RAW-GLIDE-SLOPE) instead. | Number |  {{< check/bad >}}  |
| {{< anchor id="NAV-GLIDE-SLOPE-ERROR" />}}`NAV GLIDE SLOPE ERROR` | N/A | Difference between current position and glideslope angle. Note that this provides 32 bit floating point precision, rather than the 8 bit integer precision of NAV GSI. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-GLIDE-SLOPE-LENGTH" />}}`NAV GLIDE SLOPE LENGTH` | N/A | The distance between the plane and the Glide beacon. | Feet |    |
| {{< anchor id="NAV-GSI" />}}`NAV GSI` | Navigation Index | Glideslope needle deflection (+/- 119). Note that this provides only 8 bit precision, whereas [`NAV GLIDE SLOPE ERROR`](#NAV-GLIDE-SLOPE-ERROR) provides 32 bit floating point precision. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Number |  {{< check/bad >}}  |
| {{< anchor id="NAV-GS-FLAG" />}}`NAV GS FLAG` | Navigation Index | Glideslope flag. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-GS-LATLONALT" />}}`NAV GS LATLONALT` | N/A | Returns the glide slope. | [Struct `struct`](../../simulation-variable-units/#latlonalt) structure |  {{< check/bad >}}  |
| {{< anchor id="NAV-GS-LLAF64" />}}`NAV GS LLAF64` | N/A | Nav GS latitude, longitude, altitude. | [Struct `struct`](../../simulation-variable-units/#latlonalt) structure |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-CLOSE-DME" />}}`NAV HAS CLOSE DME` | N/A | Flag if found a close station with a {{< glossterm >}}dme{{< /glossterm >}}. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-CLOSE-LOCALIZER" />}}`NAV HAS CLOSE LOCALIZER` | N/A | Flag if found a close localizer station. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-DME" />}}`NAV HAS DME` | N/A | Flag if tuned station has a {{< glossterm >}}dme{{< /glossterm >}}. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-GLIDE-SLOPE" />}}`NAV HAS GLIDE SLOPE` | N/A | Flag if tuned station has a glideslope. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-LOCALIZER" />}}`NAV HAS LOCALIZER` | N/A | Flag if tuned station is a localizer. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-NAV" />}}`NAV HAS NAV` | N/A | Flag if Nav has signal. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-HAS-TACAN" />}}`NAV HAS TACAN` | N/A | Flag if Nav has a {{< glossterm >}}tacan{{< /glossterm >}}. | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-IDENT" />}}`NAV IDENT` | N/A | {{< glossterm >}}icao_code{{< /glossterm >}}. | String |  {{< check/bad >}}  |
| {{< anchor id="NAV-LOCALIZER" />}}`NAV LOCALIZER` | N/A | Localizer course heading. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-LOC-AIRPORT-IDENT" />}}`NAV LOC AIRPORT IDENT` | N/A | The airport {{< glossterm >}}icao{{< /glossterm >}} ident for the localizer that is currently tuned on the nav radio (like 'EGLL' or 'KJFK') | String |  {{< check/bad >}}  |
| {{< anchor id="NAV-LOC-RUNWAY-DESIGNATOR" />}}`NAV LOC RUNWAY DESIGNATOR` | N/A | The letter code for the runway that the currently tuned localizer is tuned to. | String<span></span>{{< params/smallfont >}}'L' - Left<span></span>'R' - Right<span></span>'C' - Center<span></span>'W' - Water<span></span>'A' - A<span></span>'B' - B{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="NAV-LOC-RUNWAY-NUMBER" />}}`NAV LOC RUNWAY NUMBER` | N/A | NAV LOC RUNWAY NUMBER - The number portion of the runway that the currently tuned localizer is tuned to (so if the runway was 15L, this would be 15). | String<span></span>{{< params/smallfont >}}'1' - '36'<span></span>'N'<span></span>'NE'<span></span>'E'<span></span>'SE'<span></span>'S'<span></span>'SW'<span></span>'W'<span></span>'NW'{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="NAV-MAGVAR" />}}`NAV MAGVAR` | Navigation Index | Magnetic variation of tuned Nav station. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-NAME" />}}`NAV NAME` | Navigation Index | Descriptive name. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String |  {{< check/bad >}}  |
| {{< anchor id="NAV-OBS" />}}`NAV OBS` | Navigation Index | OBS setting. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-RADIAL" />}}`NAV RADIAL` | Navigation Index | Radial that aircraft is on. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-RADIAL-ERROR" />}}`NAV RADIAL ERROR` | N/A | Difference between current radial and OBS tuned radial. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-RAW-GLIDE-SLOPE" />}}`NAV RAW GLIDE SLOPE` | N/A | The glide slope angle. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-RELATIVE-BEARING-TO-STATION" />}}`NAV RELATIVE BEARING TO STATION` | N/A | Relative bearing to station. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="NAV-SIGNAL" />}}`NAV SIGNAL` | N/A | Nav signal strength. | Number |  {{< check/bad >}}  |
| {{< anchor id="NAV-SOUND" />}}`NAV SOUND` | Navigation Index | Nav audio flag. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="NAV-STANDBY-FREQUENCY" />}}`NAV STANDBY FREQUENCY` | Navigation Index | Nav standby frequency. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | MHz |  {{< check/bad >}}  |
| {{< anchor id="NAV-TOFROM" />}}`NAV TOFROM` | N/A | Returns whether the Nav is going to or from the current radial (or is off). | Enum:<span></span>{{< params/smallfont >}}0 = Off<span></span>1 = TO<span></span>2 = FROM{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="NAV-VOLUME" />}}`NAV VOLUME` | N/A | The volume of the Nav radio. | Percent |  {{< check/bad >}}  |
| {{< anchor id="NAV-VOR-DISTANCE" />}}`NAV VOR DISTANCE` | N/A | Distance of the {{< glossterm >}}vor{{< /glossterm >}} beacon. | Meters |  {{< check/bad >}}  |
| {{< anchor id="NAV-VOR-LATLONALT" />}}`NAV VOR LATLONALT` | Navigation Index | Returns the {{< glossterm >}}vor{{< /glossterm >}} station latitude, longitude and altitude. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | [Struct `struct`](../../simulation-variable-units/#latlonalt) structure |  {{< check/bad >}}  |
| {{< anchor id="NAV-VOR-LLAF64" />}}`NAV VOR LLAF64` | Navigation Index | Nav {{< glossterm >}}vor{{< /glossterm >}} latitude, longitude, altitude. Index of 1-4, depending on how many were defined in the [Nav.N](../../../../content-configuration/cfg-files/systems.cfg/#Nav.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | [Struct `struct`](../../simulation-variable-units/#latlonalt) structure |  {{< check/bad >}}  |

{{< /table-wrapper >}}


### TACAN

The table below lists all the SimVars related to the {{< glossterm >}}tacan{{< /glossterm >}} system on an aircraft. You can have either 1 or 2 of these systems, and in so all these SimVars require an index value of 1 or 2, depending on which one you want to target. Note that you must have first enabled the Tacan using the `Tacan.N` parameter in the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/) file.


{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="TACAN-ACTIVE-CHANNEL" />}}`TACAN ACTIVE CHANNEL` | Tacan Index | The active channel used by the indexed {{< glossterm >}}tacan{{< /glossterm >}} receiver on the aircraft, from 1 to 127. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Number |  {{< check/bad >}}  |
| {{< anchor id="TACAN-ACTIVE-MODE" />}}`TACAN ACTIVE MODE` | N/A | The active mode used by the indexed {{< glossterm >}}tacan{{< /glossterm >}} receiver on the aircraft, where 0 = *X* and 1 = *Y*. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="TACAN-AVAILABLE" />}}`TACAN AVAILABLE` | Tacan Index | Will be `TRUE` (1) if NAV1, NAV2, NAV3 or NAV4 can receive the indexed {{< glossterm >}}tacan{{< /glossterm >}}, or `FALSE` (0) otherwise. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="TACAN-DRIVES-NAV1" />}}`TACAN DRIVES NAV1` | Tacan Index | Tells whether the indexed {{< glossterm >}}tacan{{< /glossterm >}} is driving the Nav 1 indicator (`TRUE`, 1) or not (`FALSE`, 0), for autopilot purposes. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="TACAN-OBS" />}}`TACAN OBS` | Tacan Index | The indexed {{< glossterm >}}tacan{{< /glossterm >}} OBS setting, in degrees. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STANDBY-CHANNEL" />}}`TACAN STANDBY CHANNEL` | Tacan Index | The standby channel used by the indexed {{< glossterm >}}tacan{{< /glossterm >}} receiver on the aircraft, from 1 to 127. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Number |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STANDBY-MODE" />}}`TACAN STANDBY MODE` | Tacan Index | Indicates the indexed {{< glossterm >}}tacan{{< /glossterm >}} receiver standby mode, where 0 = *X* and 1 = *Y*. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Bool |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-CDI" />}}`TACAN STATION CDI` | Tacan Index | The CDI needle deflection amount (course deviation) to the indexed {{< glossterm >}}tacan{{< /glossterm >}} station. Can be +/- 127. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Number |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-DISTANCE" />}}`TACAN STATION DISTANCE` | Tacan Index | The distance between the indexed {{< glossterm >}}tacan{{< /glossterm >}} station position and the aircraft position. The index value refers to the Tacan receiver connected to the station. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Meter |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-IDENT" />}}`TACAN STATION IDENT` | Tacan Index | The tuned station identifier for the indexed {{< glossterm >}}tacan{{< /glossterm >}}. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | String |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-LATLONALT" />}}`TACAN STATION LATLONALT` | Tacan Index | Retrieves the latitude, longitude and altitude of the indexed {{< glossterm >}}tacan{{< /glossterm >}} station. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | [Struct `struct`](../../simulation-variable-units/#latlonalt)<span></span>structure |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-RADIAL" />}}`TACAN STATION RADIAL` | Tacan Index | The radial between the indexed {{< glossterm >}}tacan{{< /glossterm >}} station and the aircraft. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-RADIAL-ERROR" />}}`TACAN STATION RADIAL ERROR` | Tacan Index | Difference between the current radial and OBS tuned radial of the indexed {{< glossterm >}}tacan{{< /glossterm >}} station, in degrees. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Degrees. |  {{< check/bad >}}  |
| {{< anchor id="TACAN-STATION-TOFROM" />}}`TACAN STATION TOFROM` | Tacan Index | Returns whether the indexed {{< glossterm >}}tacan{{< /glossterm >}} is going *to* or *from* the current radial (or is off). Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | Enum:<span></span>{{< params/smallfont >}}0 = Off<span></span>1 = TO<span></span>2 = FROM{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="TACAN-VOLUME" />}}`TACAN VOLUME` | Tacan Index | The volume value of the indexed {{< glossterm >}}tacan{{< /glossterm >}} receiver on the aircraft. Index of 1 or 2, depending on how many were defined in the [Tacan.N](../../../../content-configuration/cfg-files/systems.cfg/#Tacan.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). | {{< glossterm >}}percent_over_100{{< /glossterm >}} |  {{< check/bad >}}  |

{{< /table-wrapper >}}


#### TCAS

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="TCAS-INTRUDER-BEARING" />}}`TCAS INTRUDER BEARING` | N/A | The bearing of {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft. | Degrees |  {{< check/bad >}}  |
| {{< anchor id="TCAS-INTRUDER-DATA" />}}`TCAS INTRUDER DATA` | N/A | The {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft data structure, which contains data about the perceived threat, returned as a struct. Struct member variables are as follows:<span></span>{{< params/smallfont >}}`id` (U64): the network ID of the intruding plane so that they are remembered in order to compute their trajectory.<span></span>`bearing` (FLOAT64): The intruder bearing, in degrees (this is bearing from track axis and not bearing from the airplane axis).<span></span>`distance` (FLOAT64): The distance between the aircraft and the intruder, in meters.<span></span>`verticalSpeed` (FLOAT64): The vertical speed of the intruder aircraft.<span></span>`relativeAltitude` (FLOAT64): The relative altitude of the intruder compared to the aircraft, in meters.<span></span>`relativeSpeed` (Vec3): The relative speed of the intruder compared to the aircraft, in {{< glossterm >}}ft{{< /glossterm >}} per second, on the x, y, and z axis.{{< /params/smallfont >}} | Struct |  {{< check/bad >}}  |
| {{< anchor id="TCAS-INTRUDER-DISTANCE" />}}`TCAS INTRUDER DISTANCE` | N/A | Disatance of {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft. | {{< glossterm >}}nm{{< /glossterm >}} |  {{< check/bad >}}  |
| {{< anchor id="TCAS-INTRUDER-NETWORK-ID" />}}`TCAS INTRUDER NETWORK ID` | N/A | Network ID of {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft. | Number |  {{< check/bad >}}  |
| {{< anchor id="TCAS-INTRUDER-RELATIVE-ALTITUDE" />}}`TCAS INTRUDER RELATIVE ALTITUDE` | N/A | Relative Altitude of {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft. | {{< glossterm >}}ft{{< /glossterm >}} |  {{< check/bad >}}  |
| {{< anchor id="TCAS-INTRUDER-RELATIVE-SPEED" />}}`TCAS INTRUDER RELATIVE SPEED` | N/A | Relative Speed of {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft. | [`SIMCONNECT_DATA_XYZ`](../../../simconnect/api-reference/structures-and-enumerations/simconnect_data_xyz/) struct, miles per second. |  {{< check/bad >}}  |
| {{< anchor id="TCAS-INTRUDER-VERTICAL-SPEED" />}}`TCAS INTRUDER VERTICAL SPEED` | N/A | Vertical Speed of {{< glossterm >}}tcas{{< /glossterm >}} intruder aircraft | {{< glossterm >}}ft{{< /glossterm >}} per second |  {{< check/bad >}}  |
| {{< anchor id="TCAS-MODE" />}}`TCAS MODE` | N/A | The current {{< glossterm >}}tcas{{< /glossterm >}} mode. | Integer:<span></span>{{< params/smallfont >}}0: STBY (OFF)<span></span>1: XPNDR<span></span>2:TA ONLY<span></span>3: AUTO (TA_RA){{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="TCAS-RECEIVED-RESOLUTION-ADVISORY" />}}`TCAS RECEIVED RESOLUTION ADVISORY` | N/A | Received RAs from intruders. | Number |  {{< check/bad >}}  |
| {{< anchor id="TCAS-SEND-RESOLUTION-ADVISORY" />}}`TCAS SEND RESOLUTION ADVISORY` | N/A | RAs to send to intruders, settable if external {{< glossterm >}}tcas{{< /glossterm >}} is defined. | Number |  {{< check/good >}}  |

{{< /table-wrapper >}}


### Misc.

{{< table-wrapper "colclass-2=font-size:0.75rem" "200px" "100px" "" "150px" "100px" >}}

| Simulation Variable | Index | Description | Units | Settable |
|---|---|---|---|:---:|
| {{< anchor id="COPILOT-TRANSMITTER-TYPE" />}}`COPILOT TRANSMITTER TYPE` | N/A | On which channel the copilot is transmitting. | Enum:<span></span>{{< params/smallfont >}}0 = COM1<span></span>1 = COM2<span></span>2 = COM3<span></span>3 = TEL<span></span>4 = NONE{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="COPILOT-TRANSMITTING" />}}`COPILOT TRANSMITTING` | N/A | Whether or not the copilot is transmitting. | Bool |  {{< check/bad >}}  |
| {{< anchor id="PILOT-TRANSMITTER-TYPE" />}}`PILOT TRANSMITTER TYPE` | N/A | On which channel the pilot is transmitting. | Enum:<span></span>{{< params/smallfont >}}0 = COM1<span></span>1 = COM2<span></span>2 = COM3<span></span>3 = TEL<span></span>4 = NONE{{< /params/smallfont >}} |  {{< check/bad >}}  |
| {{< anchor id="PILOT-TRANSMITTING" />}}`PILOT TRANSMITTING` | N/A | Whether or not the pilot is transmitting. | Bool |  {{< check/bad >}}  |
| {{< anchor id="RADIOS-AVAILABLE" />}}`RADIOS AVAILABLE` | N/A | *Currently not used within the simulation.* | - |  {{< check/bad >}}  |
| {{< anchor id="RADIO-HEIGHT" />}}`RADIO HEIGHT` | N/A | Radar altitude. | Feet |  {{< check/bad >}}  |
| {{< anchor id="TRANSPONDER-AVAILABLE" />}}`TRANSPONDER AVAILABLE` | N/A | `TRUE` if a transponder is available. | Bool |  {{< check/bad >}}  |
| {{< anchor id="TRANSPONDER-CODE" />}}`TRANSPONDER CODE` | Transponder Index | 4-digit code. Index should always be 1 and it needs to have been created in the [Transponder.N](../../../../content-configuration/cfg-files/systems.cfg/#Transponder.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). More than 1 transponder is not currently supported by the simulation. | [Bco16](../../simulation-variable-units/#Bco16) |  {{< check/bad >}}  |
| {{< anchor id="TRANSPONDER-IDENT" />}}`TRANSPONDER IDENT` | Transponder Index | This can set the Ident transponder using the [`XPNDR_IDENT_SET`](../../../key-events/aircraft-radio-navigation-events/#XPNDR_IDENT_SET), [`XPNDR_IDENT_TOGGLE`](../../../key-events/aircraft-radio-navigation-events/#XPNDR_IDENT_TOGGLE), [`XPNDR_IDENT_ON`](../../../key-events/aircraft-radio-navigation-events/XPNDR_IDENT_ON) or [`XPNDR_IDENT_OFF`](../../../key-events/aircraft-radio-navigation-events/#XPNDR_IDENT_OFF) Event IDs (see [XPNDR (Transponder)](../../../key-events/aircraft-radio-navigation-events/#xpndr-transponder) section for more information). When set to `TRUE`, it will automatically turn `FALSE` after 18 seconds. Index should always be 1 and it needs to have been created in the [Transponder.N](../../../../content-configuration/cfg-files/systems.cfg/#Transponder.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). More than 1 transponder is not currently supported by the simulation. | Bool |  {{< check/good >}}  |
| {{< anchor id="TRANSPONDER-STATE" />}}`TRANSPONDER STATE` | Transponder Index | The indexed transponder State. Index should always be 1 and it needs to have been created in the [Transponder.N](../../../../content-configuration/cfg-files/systems.cfg/#Transponder.N) parameter of the [systems.cfg](../../../../content-configuration/cfg-files/systems.cfg/). More than 1 transponder is not currently supported by the simulation. | Enum:<span></span>{{< params/smallfont >}}0 = Off<span></span>1 = Standby<span></span>2 = Test<span></span>3 = On<span></span>4 = Alt<span></span>5 = Ground{{< /params/smallfont >}} |  {{< check/good >}}  |

{{< /table-wrapper >}}