You can access the following environment variables using the E: identifier in RPN, or through SimConnect (similar to SimVars). Note that most of these variables are read-only and cannot be set, unless otherwise specified:

 

VariableUnitsDescription
ABSOLUTE TIMESecondsThis returns the seconds since 12:00 am 1/1/1AD Zulu Time) See the Note On Zulu Time for more information.
ZULU TIMESecondsThis returns the seconds since midnight (00:00 Zulu Time) on the current day.
ZULU DAY OF WEEKNumberThis returns the current Zulu Time day of the week as an integer value between 0 and 6 (inclusive), where 0 is Sunday and 6 is Saturday. See the Note On Zulu Time for more information.
ZULU DAY OF MONTHNumberThis returns the current Zulu Time day of the month as an integer value between 1 and 31 (inclusive). See the Note On Zulu Time for more information.
ZULU MONTH OF YEARNumberThis returns the current Zulu Time month of the year as an integer value between 1 and 12 (inclusive), where 1 is January and 12 is December. See the Note On Zulu Time for more information.
ZULU DAY OF YEARNumberThis returns the current Zulu Time day of the year as an integer value between 0 and 365 (365 only on a leap year). See the Note On Zulu Time for more information.
ZULU YEARNumberThis returns the current Zulu Time year as an integer value. See the Note On Zulu Time for more information.
ZULU SUNRISE TIMESecondsThis returns the seconds since midnight until the sunrise based on Zulu Time. See the Note On Zulu Time for more information.
ZULU SUNSET TIMESecondsThis returns the seconds since midnight until the sunset based on Zulu Time. See the Note On Zulu Time for more information.
LOCAL TIMESecondsThis returns the seconds since midnight (00:00 local time) on the current day.
LOCAL DAY OF WEEKNumberThis returns the current day of the week as an integer value between 0 and 6 (inclusive), where 0 is Sunday and 6 is Saturday, within the local time reference.
LOCAL DAY OF MONTHNumberThis returns the current day of the month as an integer value between 1 and 31 (inclusive), within the local time reference.
LOCAL MONTH OF YEARNumberThis returns the current month of the year as an integer value between 1 and 12 (inclusive), where 1 is January and 12 is December, within the local time reference.
LOCAL DAY OF YEARNumberThis returns the current day of the year as an integer value between 0 and 365 (365 only on a leap year), within the local time reference.
LOCAL YEARNumberThis returns the current year (local time) as an integer value.
TIME ZONE OFFSETSecondsThis returns the offset between the local time and Zulu Time. See the Note On Zulu Time for more information.
TIME OF DAYEnum(Number)This will return an integer value representing the approximate time of day where:0 = dawn1 = day2 = dusk3 = night
TOOLTIP UNITSEnum(Number)This will return an integer value representing the current units used to display tooltip information, where:0 = default1 = metric (SI)2 = US (imperial)
UNITS OF MEASUREEnum(Number)This indicates the units used to express measurements and will return an integer value representing the following:0 - English1 - Metric with altitude in feet2 - Metric with altitude in meters
SIMULATION RATENumberThis is used to get/set the internal rate of passing time within the simulation(independently of the visual frame rate). The value will be clamped between 0.0625 and 128, and a value of 1 means that 1 second of game time is the same as 1 second of “real” time, and lower values will make the game time slower, and higher values will make the game time faster. Values are always multiples of two starting at 0.0625, so you can have: 0.0625, 0.125, 0.25, 0.5, 1, 2, 4, … 128
SIMULATION TIMESecondsThis returns a value for the seconds since the simulation has been started.
SIMULATION DELTA TIMENumberThis returns a value for the time passed between the last simulation frame and the current one.
IS IN VRBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the simulation is in VR mode or not.
IS USING MOTION CONTROLLERSBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the user is using 6DoF controllers in VR or not.
IS USING JOYSTICK THROTTLEBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the user is manipulating the throttle with a joystick device or not.
IS IN RTCBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the simulation is currently running an RTC or not.
IS AVATARBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the user is in “Avatar” mode or not.
IS AIRCRAFTBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the user is in “Aircraft” mode or not.
IS CAMERA LOCKEDBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether the camera is locked or not.
EFB BRIGHTNESSPercent Over 100This return the brightness of the EFB, from 0 to 1. If it is set to “auto brightness” within the EFB’s settings, then -1 will be returned.
SWITCH USER ALWAYS ALLOWEDBooleanThis returns either 1 (TRUE) or 0 (FALSE) to indicate whether there is no limitation to switch between avatar and aircraft mode or not.

Note On Zulu Time

It should be be noted that Zulu Time is calculated off of the local time using a table of time-zones. For example, if the simulation is in a timezone that is +9 hours, then Zulu Time will be considered as current time - 9h.