Garmin G3X Pilot’s Guide190-01115-00 Rev. GAppendix D335SystemOverviewFlightInstruments EISCNSInterfaceGPSNavigationFlightPlanningHazardAvoidanceAdditionalFeaturesIntegratedAutopilot Annun/Alerts Appendix IndexAPPENDIX D: MAP DATUM AND LOCATIONFORMATSMAP DATUMSA datum is a mathematical model of the Earth that approximates the shape of theEarth and enables calculations to be carried out in a consistent and accurate manner.The datum is physically represented by a framework of ground monuments (such astrig. stations) whose locations have been accurately measured and calculated on thisreference surface. Lines of latitude and longitude on a chart are referenced to a specificmap datum. Every chart has a map datum reference and the G3X can be set to matchmost of those commonly used.LOCATION FORMATSYour current location can be viewed on the GPS in the form of coordinates. Sincedifferent charts use different location formats, Garmin GPS units allow you to choosethe correct coordinate system for the type of chart you are using. The most commonformat is latitude and longitude, which is used by all Garmin units. You can change thelocation format to use with other coordinate systems.Map Datum and Location Format selection can be performed on the Position SetupPage.Changing position settings:1) Press the MENU Key twice to display the Main Menu.2) Turn or move the FMS Joystick to highlight ‘System Setup...’ and press theENT Key.3) Turn or move the FMS Joystick to highlight ‘Position’ and press the ENTKey.4) Move the FMS Joystick to highlight the desired field, and select the desiredoption by turning the FMS Joystick.5) Press the FMS Joystick, the CLR Key, the EXIT Softkey or the MENU Key toremove the menu.
