Garmin GNC 420 - Manual (Page 6)

GNC 420(A) Pilot’s Guide and Reference iv
WARNINGS,
CAUTIONS, AND NOTES
WARNING: Navigation and terrain separation must NOT be predicated upon the use of the TerraiN function.
The TerraiN feature is NOT intended to be used as a primary reference for terrain avoidance and does not
relieve the pilot from the responsibility of being aware of surroundings during flight. The TerraiN feature is
only to be used as an aid for terrain avoidance and is not certified for use in applications requiring a certified
terrain awareness system. Terrain data is obtained from third party sources. Garmin is not able to independently
verify the accuracy of the terrain data.
WARNING: The terrain data should be used only as an aid for situational awareness. Terrain data must not
be used as the sole basis for decisions or maneuvers to avoid terrain or obstacles. Terrain data must not be
used for navigation.
WARNING: The altitude calculated by GNC 420 GPS receivers is geometric height above Mean Sea Level and
could vary significantly from the altitude displayed by pressure altimeters in aircraft. GPS altitude should never
be used for vertical navigation. always use pressure altitude displayed by pressure altimeters in the aircraft.
WARNING: The Jeppesen database used in the GNC 420 system must be updated regularly in order to ensure
that its information remains current. Updates are released every 28 days. a database information packet is
included in the GNC 420 package. Pilots using an outdated database do so entirely at their own risk.
WARNING: The basemap (land and water data) must not be used for navigation, but rather only for non-nav-
igational situational awareness. any basemap indication should be compared with other navigation sources.
WARNING: For safety reasons, GNC 420 operational procedures must be learned on the ground.
WARNING: The United States government operates the Global Positioning System and is solely responsible
for its accuracy and maintenance. The GPS system is subject to changes which could affect the accuracy and
performance of all GPS equipment. Portions of the Garmin GNC 420 utilize GPS as a precision electronic
NaVigation aiD (NaVaiD). Therefore, as with all NaVaiDs, information presented by the GNC 420 can be
misused or misinterpreted and, therefore, become unsafe.
WARNING: The GTS 8XX interface is intended for advisory use only to aid the pilot in visually acquiring traffic.
No avoidance maneuvers should be based solely upon TaS or TCaS traffic information. it is the responsibility
of the pilot in command to see and manuever to avoid traffic.
190-00140-20 Rev. K