Garmin 430w Manual

41
Terrain Operation
Restoring Factory Settings
“Restore Defaults?” resets all four user-selectable 
data fields to their original factory default settings. 
To restore the factory default settings, press 
MENU and turn the large right knob to highlight 
“Restore Defaults?”, then press ENT. 
Terrain Operation
During power-up of the 400W Series unit, the 
terrain/obstacle database versions are displayed along 
with a disclaimer. At the same time, the Terrain system 
self-test begins. A failure message is...

42
 NOTE:  The data contained in the TERRAIN data-
bases comes from government agencies. Garmin 
accurately processes and cross-validates the data 
but cannot guarantee the accuracy and complete-
ness of the data. 
TERRAIN Alerting
TERRAIN uses information provided from the GPS 
receiver to provide a horizontal position and altitude.  
GPS altitude is derived from satellite measurements. GPS 
altitude is converted to a mean sea level (MSL)-based 
altitude (GSL altitude) and is used to determine TERRAIN...

43
Terrain Operation
To display a 120˚ view: 
1.  Select the TERRAIN Page and press MENU. 
2.  Select “View 120˚?”. 
3. Press ENT. To switch back to a 360˚ view, 
repeat step 1, select “View 360˚?”, and press 
ENT. 
Seven display ranges are available, allowing for a 
more complete view of the surrounding area. 
To change the display range: 
1.  Select the TERRAIN Page and press up or down 
on the RNG key to select the desired range:  
1 NM, 2 NM, 5 NM, 10 NM, 25 NM, 50 NM, 
100 NM. 
Aviation information...

44
To  enable TERRAIN: 
Enabling Terrain
1.  Select the TERRAIN Page and press MENU.  
“Enable Terrain?” is selected by default. 
2. Press ENT. The TERRAIN system is functional 
again. 
Terrain Symbols
The symbols shown below are used to represent 
obstacles and potential impact points on the Terrain 
Page. Note that obstacle symbols are shown on display 
zoom ranges up to 10 NM: 
The Garmin TERRAIN system uses yellow (caution) 
and red (warning) to depict terrain information relative 
to aircraft...

45
Terrain Operation
General Database Information
The Garmin TERRAIN system uses terrain and 
obstacle information supplied by government sources. 
The data undergoes verification by Garmin to confirm 
accuracy of the content, per TSO-C151b. However, the 
information displayed should never be understood to 
be all-inclusive. Pilots must familiarize themselves 
with the appropriate charts for safe flight. 
 NOTE:  The data contained in the terrain and 
obstacle databases comes from government 
agencies....

46
To update the terrain or obstacle database:
1.  Acquire a new terrain data card from 
Garmin. 
2.  Turn off the power to the 400W Series unit. 
3.  Remove the old terrain data card from and 
insert the new card into the right-most slot of 
the 400W Series unit. 
4.  Turn on the 400W Series unit and verify that the 
TERRAIN system passes the self-test. The “TER 
TEST” annunciator will clear after checking and 
no failure message appears. 
Terrain/Obstacle Database Areas of Coverage
The following...

47
Terrain Alerts
Forward  Looking Terrain Avoidance
The unit will issue terrain alerts not only when the 
aircraft altitude is below the terrain elevation but also 
when the aircraft is projected to come within minimum 
clearance values of the terrain. This alerting, called 
Forward Looking Terrain Avoidance (FLTA), is also 
provided for obstacles. Any potential impact points will 
be depicted on the display. 
FLTA Severity Levels
“TERRAIN AHEAD” alert (flashing)—Similarly, an “OBSTACLE AHEAD’’ alert is...

48
Premature  Descent Alerting (PDA)
The TERRAIN system issues a Premature Descent 
Alert (PDA) when the system detects that the aircraft 
is significantly below the normal approach path to a 
runway. 
 PDA ends when the aircraft is either:   
•  0.5 NM from the runway threshold  
OR  
•  is below an altitude of 125 feet AGL while 
within  
   1.0 NM of the threshold. 
CAUTION — The above annunciation and pop-up 
terrain alert are displayed during a PDA alert. 
PDA Severity Levels
TERRAIN  Failure Alert...

49
Terrain Alerts
“TERRAIN  Not Available” Alert
The TERRAIN system requires a 3D GPS 
navigation solution along with specific vertical 
accuracy minimums. Should the navigation solution 
become degraded, or if the aircraft is out of the 
database coverage area, the annunciation “TERRAIN 
NOT AVAILABLE” is displayed on the TERRAIN Page. 
“TERRAIN NOT AVAILABLE” display
2 - NAV PAGES 
190-00356-00 Rev K  

50
AnnunciationPop-Up AlertDescription
NoneTERRAIN has failed
NoneTERRAIN has been inhibited
NoneTERRAIN not available due to degraded navigation solution 
or the aircraft is outside of the database coverage area. 
Terrain FLTA advisory generated by predicted or present 
aircraft altitude being below minimum clearance values. 
Unless there is a change in conditions a TERRAIN AHEAD 
alert may be  
generated. 
(FLASHING)(FLASHING)
Terrain FLTA alert generated by predicted or present aircraft 
altitude...