AIRCRAFT RADIO NAVIGATION VARIABLES
The tables below indicate the properties for the 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
NOTE: When Microsoft Flight Simulator 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".
You can find a complete index of all available SimVars here: SimVar Index
ADF
Simulation Variable | Description | Units | Settable |
---|---|---|---|
ADF ACTIVE FREQUENCY:index |
ADF frequency. Index of 1 or 2. | Frequency ADF BCD32 | |
ADF AVAILABLE:index |
True if ADF is available | Bool | |
ADF CARD |
ADF compass rose setting | Degrees | |
ADF EXT FREQUENCY |
Deprecated, use ADF ACTIVE FREQUENCY |
Frequency BCD16 | |
ADF FREQUENCY |
Deprecated, use ADF ACTIVE FREQUENCY |
Frequency BCD16 | |
ADF IDENT |
ICAO code | String | |
ADF LATLONALT: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 for ADF 1 and ADF 2. |
structure |
|
ADF NAME:index |
Descriptive name | String | |
ADF RADIAL:index |
Current direction from NDB station | Degrees | |
ADF RADIAL MAG:index |
Returns the magnetic bearing to the currently tuned ADF transmitter. | Degrees | |
ADF SIGNAL:index |
Signal strength | Number | |
ADF SOUND:index |
ADF audio flag. Index of 0 or 1. | Bool | |
ADF STANDBY AVAILABLE:index |
True if ADF Standby is available | Bool | |
ADF STANDBY FREQUENCY:index |
ADF standby frequency | Hz | |
ADF VOLUME |
Returns the volume of the ADF | Percent Over 100 |
ATC
COM
FLARM
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
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.
Simulation Variable | Description | Units | Settable |
---|---|---|---|
GPS APPROACH AIRPORT ID |
ID of airport. | String | |
GPS APPROACH APPROACH ID |
ID of approach. | String | |
GPS APPROACH APPROACH INDEX |
Index of approach for given airport. | Number | |
GPS APPROACH APPROACH TYPE |
Approach type. |
Enum: |
|
GPS APPROACH IS FINAL |
Is approach transition final approach segment. | Bool | |
GPS APPROACH IS MISSED |
Is approach segment missed approach segment. | Bool | |
GPS APPROACH IS WP RUNWAY |
Waypoint is the runway. | Bool | |
GPS APPROACH MODE |
Sub mode within approach mode. |
Enum:
|
|
GPS APPROACH SEGMENT TYPE |
Segment type within approach. |
Enum:
|
|
GPS APPROACH TIMEZONE DEVIATION |
Deviation of local time from GMT. | Seconds | |
GPS APPROACH TRANSITION ID |
ID of approach transition. | String | |
GPS APPROACH TRANSITION INDEX |
Index of approach transition. | Number | |
GPS APPROACH WP COUNT |
Number of waypoints. | Number | |
GPS APPROACH WP INDEX |
Index of current waypoint. | Number | |
GPS APPROACH WP TYPE |
Waypoint type within approach mode. |
Enum:
|
|
GPS CDI NEEDLE |
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 simvar. |
Number | |
GPS CDI SCALING |
The full scale deflection of the CDI due to GPS cross-track error, in meters. | Meters | |
GPS COURSE TO STEER |
Suggested heading to steer (for autopilot). | Radians | |
GPS DRIVES NAV1 |
GPS is driving Nav 1 indicator. Note this setting will also affect the SimVars HSI_STATION_IDENT and HSI_BEARING . |
Bool | |
GPS ETA |
Estimated time of arrival at destination. | Seconds | |
GPS ETE |
Estimated time en route to destination. | Seconds | |
GPS FLIGHTPLAN TOTAL DISTANCE |
This is the complete flightplan length from start to end. Essentially the cumulative length of all the flight plan legs added together. |
Meters |
|
GPS FLIGHT PLAN WP COUNT |
Number of waypoints. | Number | |
GPS FLIGHT PLAN WP INDEX |
Index of waypoint. | Number | |
GPS GROUND MAGNETIC TRACK |
Current magnetic ground track. | Radians | |
GPS GROUND SPEED |
Current ground speed. | Meters per second | |
GPS GROUND TRUE HEADING |
Current true heading. | Radians | |
GPS GROUND TRUE TRACK |
Current true ground track. | Radians | |
GPS GSI SCALING |
The full scale deflection of the vertical GSI due to GPS glidepath deviation, in meters. | Meters | |
GPS HAS GLIDEPATH |
Whether or not the GPS system has a presently available glidepath for guidance. Only applicable with GPS_OVERRIDDEN . When true and in GPS OVERRIDDEN , HSI_GSI_NEEDLE_VALID will also be true. |
Bool | |
GPS HSI NEEDLE |
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 simvar. |
Number | |
GPS IS ACTIVE FLIGHT PLAN |
Flight plan mode active. | Bool | |
GPS IS ACTIVE WAY POINT |
Waypoint mode active. | Bool | |
GPS IS ACTIVE WP LOCKED |
Is switching to next waypoint locked. | Bool | |
GPS IS APPROACH ACTIVE |
Is approach mode active. | Bool | |
GPS IS APPROACH LOADED |
Is approach loaded. | Bool | |
GPS IS ARRIVED |
Is flight plan destination reached. | Bool | |
GPS IS DIRECTTO FLIGHTPLAN |
Is Direct To Waypoint mode active. | Bool | |
GPS MAGVAR |
Current GPS magnetic variation. | Radians | |
GPS OBS ACTIVE |
Whether or not the OBS mode is currently active (disable the automatic sequencing of waypoints in GPS flight plan). | Bool | |
GPS OBS VALUE |
This is the currently selected OBS course in degrees, from 0 to 360. | Degrees | |
GPS OVERRIDDEN |
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 | |
GPS POSITION ALT |
Current GPS altitude. | Meters | |
GPS POSITION LAT |
Current GPS latitude. | Degrees | |
GPS POSITION LON |
Current GPS longitude. | Degrees | |
GPS TARGET ALTITUDE |
Altitude of GPS target. | Meters | |
GPS TARGET DISTANCE |
Distance to target. | Meters | |
GPS VERTICAL ANGLE |
Glidepath in degrees. | Degrees | |
GPS VERTICAL ANGLE ERROR |
Vertical error in degrees from GlidePath. | Degrees | |
GPS VERTICAL ERROR |
Vertical deviation in meters from GlidePath. | Meters | |
GPS WP BEARING |
Magnetic bearing to waypoint. | Radians | |
GPS WP CROSS TRK |
Cross track distance. | Meters | |
GPS WP DESIRED TRACK |
The required heading (magnetic) from the previous waypoint to the next waypoint. | Radians | |
GPS WP DISTANCE |
Distance to waypoint. | Meters | |
GPS WP ETA |
Estimated time of arrival at waypoint. | Seconds | |
GPS WP ETE |
Estimated time en route to waypoint. | Seconds | |
GPS WP NEXT ALT |
Altitude of next waypoint. | Meters | |
GPS WP NEXT ID |
ID of next GPS waypoint. | String | |
GPS WP NEXT LAT |
Latitude of next waypoint. | Degrees | |
GPS WP NEXT LON |
Longitude of next waypoint. | Degrees | |
GPS WP PREV ALT |
Altitude of previous waypoint. | Meters | |
GPS WP PREV ID |
ID of previous GPS waypoint. | String | |
GPS WP PREV LAT |
Latitude of previous waypoint. | Degrees | |
GPS WP PREV LON |
Longitude of previous waypoint. | Degrees | |
GPS WP PREV VALID |
Is previous waypoint valid (i.e. current waypoint is not the first waypoint). | Bool | |
GPS WP TRACK ANGLE ERROR |
Tracking angle error to waypoint. | Radians | |
GPS WP TRUE BEARING |
True bearing to waypoint. | Radians | |
GPS WP TRUE REQ HDG |
Required true heading to waypoint. | Radians | |
GPS WP VERTICAL SPEED |
Vertical speed to waypoint. | Meters per second |
HSI
Simulation Variable | Description | Units | Settable |
---|---|---|---|
HSI BEARING |
If the GPS_DRIVES_NAV1 variable is true and the HSI BEARING VALID variable is true, this variable contains the HSI needle bearing. If the GPS DRIVES NAV1 variable is false and the HSI BEARING VALID variable is true, this variable contains the ADF1 frequency. |
Degrees | |
HSI BEARING VALID |
This will return true if the HSI BEARING variable contains valid data. |
Bool | |
HSI CDI NEEDLE |
Needle deflection (+/- 127). | Number | |
HSI CDI NEEDLE VALID |
Signal valid. | Bool | |
HSI DISTANCE |
DME/GPS distance. | Nautical miles | |
HSI GSI NEEDLE |
Needle deflection (+/- 119). | Number | |
HSI GSI NEEDLE VALID |
Signal valid. | Bool | |
HSI HAS LOCALIZER |
Station is a localizer. | Bool | |
HSI SPEED |
DME/GPS speed. | Knots | |
HSI STATION IDENT |
Returns the ident of the the next GPS waypoint, if 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 | |
HSI TF FLAGS |
Nav TO/FROM flag. |
Enum:
|
MARKERS
NAV
Simulation Variable | Description | Units | Settable |
---|---|---|---|
NAV ACTIVE FREQUENCY:index |
Nav active frequency. Index is 1 or 2. | MHz | |
NAV AVAILABLE:index |
Flag if Nav equipped on aircraft. | Bool | |
NAV BACK COURSE FLAGS:index |
Returns the listed bit flags. |
Flags:
|
|
NAV CDI:index |
CDI needle deflection (+/- 127). | Number | |
NAV CLOSE DME:index |
Closest DME distance. Requires an index value from 1 to 4 to set which NAV to target. Note that this SimVar will only work if the |
Nautical miles | |
NAV CLOSE FREQUENCY:index |
Closest Localizer course frequency. Requires an index value from 1 to 4 to set which NAV to target.
Note that this SimVar will only work if the |
Hz | |
NAV CLOSE IDENT:index |
ICAO code. Requires an index value from 1 to 4 to set which NAV to target.
Note that this SimVar will only work if the |
String | |
NAV CLOSE LOCALIZER:index |
Closest Localizer course heading. Requires an index value from 1 to 4 to set which NAV to target.
Note that this SimVar will only work if the |
Degrees | |
NAV CLOSE NAME:index |
Descriptive name. Requires an index value from 1 to 4 to set which NAV to target.
Note that this SimVar will only work if the |
String | |
NAV CODES |
Returns bit flags with the listed meaning. |
Flags:
|
|
NAV DME |
DME distance. | Nautical miles | |
NAV DMESPEED |
DME speed. | Knots | |
NAV DME LATLONALT:index |
Returns the DME station. | SIMCONNECT_DATA_LATLONALT structure |
|
NAV FREQUENCY |
Localizer course frequency | Hz | |
NAV GLIDE SLOPE |
The glide slope gradient. The value returned is an integer value formed as follows: sin(slope) * 65536 * 2 So, for example, a glide slope of 2.7º would return a value of 6174. TO get the value in degrees, then use |
Number | |
NAV GLIDE SLOPE ERROR |
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 | |
NAV GLIDE SLOPE LENGTH |
The distance between the plane and the Glide beacon. | Feet | |
NAV GSI |
Glideslope needle deflection (+/- 119). Note that this provides only 8 bit precision, whereas NAV GLIDE SLOPE ERROR provides 32 bit floating point precision. | Number | |
NAV GS FLAG |
Glideslope flag. | Bool | |
NAV GS LATLONALT:index |
Returns the glide slope. | SIMCONNECT_DATA_LATLONALT structure |
|
NAV GS LLAF64 |
Nav GS latitude, longitude, altitude. | SIMCONNECT_DATA_LATLONALT structure |
|
NAV HAS CLOSE DME |
Flag if found a close station with a DME. | Bool | |
NAV HAS CLOSE LOCALIZER |
Flag if found a close localizer station. | Bool | |
NAV HAS DME |
Flag if tuned station has a DME. | Bool | |
NAV HAS GLIDE SLOPE |
Flag if tuned station has a glideslope. | Bool | |
NAV HAS LOCALIZER |
Flag if tuned station is a localizer. | Bool | |
NAV HAS NAV |
Flag if Nav has signal. | Bool | |
NAV HAS TACAN |
Flag if Nav has a Tacan. | Bool | |
NAV IDENT |
ICAO code. | String | |
NAV LOCALIZER |
Localizer course heading. | Degrees | |
NAV LOC AIRPORT IDENT |
The airport ICAO ident for the localizer that is currently tuned on the nav radio (like 'EGLL' or 'KJFK') | String | |
NAV LOC RUNWAY DESIGNATOR |
The letter code for the runway that the currently tuned localizer is tuned to. | String
|
|
NAV LOC RUNWAY NUMBER |
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
|
|
NAV MAGVAR |
Magnetic variation of tuned Nav station. | Degrees | |
NAV NAME |
Descriptive name. | String | |
NAV OBS |
OBS setting. Index of 1 or 2. | Degrees | |
NAV RADIAL |
Radial that aircraft is on. | Degrees | |
NAV RADIAL ERROR |
Difference between current radial and OBS tuned radial. | Degrees | |
NAV RAW GLIDE SLOPE |
The glide slope angle. | Degrees | |
NAV RELATIVE BEARING TO STATION |
Relative bearing to station. | Degrees | |
NAV SIGNAL |
Nav signal strength. | Number | |
NAV SOUND:index |
Nav audio flag. Index of 1 or 2. | Bool | |
NAV STANDBY FREQUENCY:index |
Nav standby frequency. Index is 1 or 2. | MHz | |
NAV TOFROM |
Returns whether the Nav is going to or from the current radial (or is off). |
Enum:
|
|
NAV VOLUME |
The volume of the Nav radio. | Percent | |
NAV VOR DISTANCE |
Distance of the VOR beacon. | Meters | |
NAV VOR LATLONALT:index |
Returns the VOR station latitude, longitude and altitude. | SIMCONNECT_DATA_LATLONALT structure |
|
NAV VOR LLAF64 |
Nav VOR latitude, longitude, altitude. | SIMCONNECT_DATA_LATLONALT structure |
TACAN
The table below lists all the SimVars related to the Tacan 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 file.
Simulation Variable | Description | Units | Settable |
---|---|---|---|
TACAN ACTIVE CHANNEL:index |
The active channel used by the indexed Tacan receiver on the aircraft, from 1 to 127. | Number | |
TACAN ACTIVE MODE:index |
The active mode used by the indexed Tacan receiver on the aircraft, where 0 = X and 1 = Y. | Bool | |
TACAN AVAILABLE:index |
Will be TRUE (1) if NAV1, NAV2, NAV3 or NAV4 can receive Tacan (depending on the index - 1, 2, 3, or 4), or FALSE (0) otherwise. | Bool | |
TACAN DRIVES NAV1:index |
Tells whether the Tacan is driving the Nav 1 indicator (TRUE, 1) or not (FALSE, 0), for autopilot purposes. | Bool | |
TACAN OBS:index |
The Tacan OBS setting, in degrees. | Degrees | |
TACAN STANDBY CHANNEL:index |
The standby channel used by the indexed Tacan receiver on the aircraft, from 1 to 127. | Number | |
TACAN STANDBY MODE:index |
Indicates the indexed Tacan receiver standby mode, where 0 = X and 1 = Y. | Bool | |
TACAN STATION CDI:index |
The CDI needle deflection amount(course deviation) to the station. Can be +/- 127. | Number | |
TACAN STATION DISTANCE:index |
The distance between the Tacan station position and the aircraft position. The index value refers to the Tacan receiver connected to the station (1 or 2). | Meter | |
TACAN STATION IDENT:index |
The tuned station identifier for the indexed Tacan. | String | |
TACAN STATION LATLONALT:index |
Retrieves the latitude, longitude and altitude of the Tacan station. |
structure |
|
TACAN STATION RADIAL:index |
The radial between the Tacan station and the aircraft. | Degrees | |
TACAN STATION RADIAL ERROR:index |
Difference between the current radial and OBS tuned radial, in degrees. | Degrees. | |
TACAN STATION TOFROM:index |
Returns whether the indexed Tacan is going to or from the current radial (or is off). |
Enum:
|
|
TACAN VOLUME:index |
The volume value of the indexed Tacan receiver on the aircraft. | Percent Over 100 |
Misc.
Simulation Variable | Description | Units | Settable |
---|---|---|---|
COPILOT TRANSMITTER TYPE |
On which channel the copilot is transmitting. |
Enum:
|
|
COPILOT TRANSMITTING |
Whether or not the copilot is transmitting. | Bool | |
PILOT TRANSMITTER TYPE |
On which channel the pilot is transmitting. |
Enum:
|
|
PILOT TRANSMITTING |
Whether or not the pilot is transmitting. | Bool | |
RADIOS AVAILABLE |
Currently not used within the simulation. | - | |
RADIO HEIGHT |
Radar altitude. | Feet | |
TRANSPONDER AVAILABLE |
True if a transponder is available. | Bool | |
TRANSPONDER CODE:index |
4-digit code. | BCD16 | |
TRANSPONDER IDENT |
This can set the Ident transponder using the KEY_XPNDR_IDENT_SET , KEY_XPNDR_IDENT_TOGGLE , KEY_XPNDR_IDENT_ON or KEY_XPNDR_IDENT_OFF Event IDs (see XPNDR (Transponder) section for more information). When set to true, it will automatically turn false after 18 seconds. |
Bool | |
TRANSPONDER STATE |
Transponder State. |
Enum:
|