2 - NAV PAGES45Terrain OperationTo update the terrain or obstacle database:1. Acquire a new terrain data card fromGarmin.2. Turn off the power to the 400W Series unit.3. Remove the old terrain data card from andinsert the new card into the right-most slot ofthe 400W Series unit.4. Turn on the 400W Series unit and verify that theTERRAIN system passes the self-test. The “TERTEST” annunciator will clear after checking andno failure message appears.Terrain/Obstacle Database Areas of CoverageThe following describes the area of coverage avail-able in each database. Regional definitions may changewithout notice.The terrain and airport terrain databases includeworldwide coverage that includes: Latitudes South 60°to North 75°.The obstacle database provides coverage for theUSA and Europe that includes:United States: Limited to the United States, someareas of Canada, Mexico, the Caribbean, and thePacific.Europe: Limited to Austria, Belgium, Czech Repub-lic, Denmark, Estonia, Finland, France, Germany,Greece, Iceland, Ireland, Italy, Latvia, Lithuania, Neth-erlands, Norway, Poland, Portugal, Slovakia, Spain,Sweden, Switzerland, and the United Kingdom.CAUTION: Obstacles 200 feet and higher are in-cluded in the Obstacle Database. It is very impor-tant to note that not all obstacles are necessarilycharted and therefore may not be contained inthe Obstacle Database.Navigation DatabaseAs explained in the “Premature Descent Alert-ing (PDA)” section, the Garmin TERRAIN prema-ture descent alerting (PDA) algorithms utilize datacontained in the Navigation Database. It is thereforeimportant to also have the latest Navigation Databaseinstalled to ensure correct TERRAIN alerting.Terrain Phase of FlightThe TERRAIN Phase of Flight definitions are listedbelow:En Route Phase - Defined as when the conditionsfor Terminal, Approach, and Departure Phases are notmet.Terminal Phase - Defined as when all three of thefollowing conditions are met:• The aircraft is 15 NM or less from the destinationrunway.• The distance to the destination runway thresholdis decreasing.• The aircraft is at or below (lower than) a straightline drawn between the two points specified in thetable below (relative to the destination runway).Distance to Runway Height above Runway15 NM 3500 feet5 NM 1900 feetApproach Phase - Defined as when all three ofthe following conditions are met:• The distance to the destination runway thresholdis equal to or less than 5 NM.• The height above the destination runway thresh-old elevation is equal to or less than 1000 feet.• The distance to the destination runway thresholdis decreasing.
