Garmin aera 795/796 Pilot’s Guide190-01194-00 Rev. AAppendix I179Overview GPS Navigation Flight Planning Hazard Avoidance Additional Features Appendices IndexAPPENDIX I: 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 onthis reference surface. Lines of latitude and longitude on a chart are referenced to aspecific map datum. Every chart has a map datum reference and the aera 795/796 canbe set to match most 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. Several other grids, including auser-definable grid (for the advanced user), are available.
