Garmin 500W Series Pilot's Manual & Reference

Also see for 400W Series: Supplemental Flight manual Pilot's guide addendum Manual supplement Pilot's guide addendum Quick reference guide

Contents

Garmin 500W Series Pilot's Manual & Reference Manual pdf 53 page image

2 - NAV PAGES43190-00357-00 Rev BTerrain OperationDuring power-up of the 500W Series unit, theterrain/obstacle database versions are displayed alongwith a disclaimer. At the same time, the Terrain systemself-test begins. A failure message is issued if the test fails.Garmin TERRAIN is a non-TSO-C151b-certifiedterrain awareness system provided as a standard featureof 500W-Series units to increase situational awarenessand help reduce controlled flight into terrain (CFIT).TAWS is an optional feature on 500W-Series units.Information on TAWS is provided in the 400W/500WSeries Optional Displays Addendum,p/n 190-00356-30.Operating CriteriaTERRAIN requires the following to operate properly:• The system must have a valid 3-D GPS positionsolution.• The system must have a valid terrain/obstacle/air-port terrain database.Terrain LimitationsNOTE: 500W-Series units may display either a TERRAINPage or a TAWS Page, (or neither, but not both) dependingupon the installed hardware and conifguration.TERRAIN displays terrain and obstructions relative tothe altitude of the aircraft. The displayed alerts are advisoryin nature only. Individual obstructions may be shownif available in the database. However, all obstructionsmay not be available in the database and data may beinaccurate. Never use this information for navigation or tomaneuver to avoid obstacles.Terrain information is based on terrain elevationinformation in a database that may contain inaccuracies.Terrain information should be used as an aid to situationalawareness. Never use it for navigation or to maneuver toavoid terrain.TERRAIN uses terrain and obstacle informationsupplied by government sources. The data undergoesverification by Garmin to confirm accuracy of the content,per TSO-C151b. However, the displayed informationshould never be understood as being all-inclusive.NOTE: The data contained in the TERRAIN databasescomes from government agencies. Garmin accuratelyprocesses and cross-validates the data but cannotguarantee the accuracy and completeness of the data.TERRAIN AlertingTERRAIN uses information provided from the GPSreceiver to provide a horizontal position and altitude.GPS altitude is derived from satellite measurements. GPSaltitude is converted to a mean sea level (MSL)-basedaltitude (GPS-MSL altitude) and is used to determineTERRAIN alerts. GPS-MSL altitude accuracy is affectedby factors such as satellite geometry, but it is not subjectto variations in pressure and temperature that normallyaffect pressure altitude devices. GPS-MSL altitude does notrequire local altimeter settings to determine MSL altitude.Therefore, GPS altitude provides a highly accurate andreliable MSL altitude source to calculate terrain andobstacle alerts.TERRAIN utilizes terrain and obstacle databases thatare referenced to mean sea level (MSL). Using the GPSposition and GPS-MSL altitude, TERRAIN displays a 2-Dpicture of the surrounding terrain and obstacles relativeto the position and altitude of the aircraft. Furthermore,the GPS position and GPS-MSL altitude are used tocalculate and “predict” the aircraft’s flight path in relationto the surrounding terrain and obstacles. In this manner,TERRAIN can provide advanced alerts of predicteddangerous terrain conditions. Detailed alert modes aredescribed later in this section.Terrain Operation190-00357-00_0B 500W Pilot Guide43 43 9/7/2007 3:10:04 PM