Garmin 430w Manual

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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 issued if the test fails. 
Garmin TERRAIN is a non-TSO-C151b-certified 
terrain awareness system provided as a standard feature 
of 400W-Series units to increase situational awareness 
and help reduce controlled flight into terrain (CFIT). 
For units with installed in helicopters or equipped 
with optional HTAWS, refer to 400W/500W Series Garmin 
Optional Displays, P/N 190-00356-30 Rev G, or later. 
Operating Criteria
TERRAIN requires the following to operate properly: 
• The system must have a valid 3-D GPS position 
solution. 
• The system must have a valid terrain/obstacle/air-
port terrain database. 
Terrain Limitations
TERRAIN displays terrain and obstructions relative 
to the altitude of the aircraft.  The displayed alerts are 
advisory in nature only. Individual obstructions may be 
shown if available in the database. However, all obstruc-
tions may not be available in the database and data may 
be inaccurate. Never use this information for navigation 
or to maneuver to avoid obstacles. 
Terrain information is based on terrain elevation 
information in a database that may contain inaccuracies.  
Terrain information should be used as an aid to situational 
awareness. Never use it for navigation or to maneuver to 
avoid terrain. 
TERRAIN 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 displayed information 
should never be understood as being all-inclusive. 
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 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 
alerts. GSL altitude accuracy is affected by factors such 
as satellite geometry, but it is not subject to variations in 
pressure and temperature that normally affect pressure 
altitude devices. GSL altitude does not require local 
altimeter settings to determine MSL altitude. Therefore, 
GPS altitude provides a highly accurate and reliable MSL 
altitude source to calculate terrain and obstacle alerts. 
TERRAIN utilizes terrain and obstacle databases that are 
referenced to mean sea level (MSL). Using the GPS position 
and GSL altitude, TERRAIN displays a 2-D picture of the 
surrounding terrain and obstacles relative to the position 
and altitude of the aircraft. Furthermore, the GPS position 
and GSL altitude are used to calculate and “predict” the 
aircraft’s flight path in relation to the surrounding terrain 
and obstacles. In this manner, TERRAIN can provide 
advanced alerts of predicted dangerous terrain conditions. 
Detailed alert modes are described later in this section. 
Baro-Corrected Altitude
Baro-corrected altitude (or indicated altitude) is derived 
by adjusting the altimeter setting for local atmospheric 
conditions. The most accurate baro-corrected altitude 
can be achieved by frequently updating the altimeter 
setting to the nearest reporting station along the flight 
path. However, because actual atmosphere conditions 
seldom match the standard conditions defined by the 
International Standard Atmosphere (ISA) model (where 
pressure, temperature, and lapse rates have fixed values), 
it is common for the baro-corrected altitude (as read from 
the altimeter) to differ from the GPS-MSL altitude. This 
variation results in the aircraft’s true altitude differing from 
the baro-corrected altitude. 
Terrain Page 
To display the TERRAIN Page, select the NAV 
group and turn the small right knob until the 
TERRAIN Page is displayed. The page displays terrain 
information, aircraft ground track, and GPS-derived 
MSL altitude (GSL altitude). Altitude is shown in 
increments of 20 feet or in increments of 10 meters, 
depending on unit configuration. 
The TERRAIN Page has two selectable view 
settings: 
• 360˚ View—View from above aircraft depicting 
surrounding terrain on all sides 
• 120˚ View—View of terrain ahead of and 60˚ to 
either side of the aircraft flight path 
TERRAIN Page
 NOTE:  The TERRAIN Page gives a “Track Up” dis-
play orientation, as indicated by the “TRK” label 
shown on the display. This is the only orientation 
available on this page. 
Terrain Operation
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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 such as airports, VORs, 
and other navaids can be turned on or off from the 
TERRAIN Page. 
To show or hide aviation data:
1.  Select the TERRAIN Page and press MENU. 
2.  Select “Show (or Hide) Aviation Data” and 
press ENT. Pressing the CLR key when the 
TERRAIN Page is displayed will also toggle 
aviation information on or off. 
Inhibit Mode
The Garmin TERRAIN system provides an 
“inhibit mode”. This mode is designed to deactivate 
Premature Descent Alert/Forward Looking Terrain 
Avoidance (PDA/FLTA)  visual alerts when they are 
deemed unnecessary by the pilot. Flying VFR into 
an area where unique terrain exists could cause the 
system to annunciate a nuisance alert. Pilots should 
use discretion when inhibiting the TERRAIN system 
and always remember to enable the system when 
appropriate. When terrain is inhibited, the Terrain 
page will still be active, but alerts and messages will 
not be generated. See the Terrain Alerts section for 
more information on terrain alerts. 
TERRAIN configured units will restore the “inhibit 
state” at startup to the last pilot-selected setting. 
Inhibiting Terrain
To  inhibit TERRAIN:
1.  Select the TERRAIN Page and press MENU. 
“Inhibit Terrain?” is selected by default. 
2. Press ENT. The TERRAIN system is inhibited.  
The  annunciation is displayed in 
the terrain annunciator field whenever terrain 
is inhibited. 
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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 altitude. Each color is associated with an 
alert severity level. Terrain graphics and visual annun-
ciations also use these color assignments. 
 NOTE:  If an obstacle and the projected flight 
path of the aircraft intersect, the display auto-
matically zooms in to the closest potential point 
of impact on the TERRAIN page. 
Terrain Operation
Obstacle Symbol
Unlighted Obstacle Lighted ObstacleColor
(Alert Level) TERRAIN/Obstacle  
Location
<  1000’ AGL >  1000’ AGL<  1000’ AGL>  1000’ AGL
Red
(Warning)
Terrain/Obstacle above or 
within 100 ft below current 
aircraft altitude 
Yellow
(Caution)Terrain/Obstacle between 
100 ft and 1000 ft below the 
aircraft altitude 
Terrain Color Symbology
Potential Impact Point
Unlighted Obstacle
Projected Flight Path
1000 ft 
100 ft Threshold 
Te
rrain more than 1000 ft below the aircraft altitude (Black) Te
rrain between 100 ft and 1000 ft below the 
aircraft altitude (Y ellow)
Terrain above or
 within 100 ft 
below the aircraft
altitude (Red)
 
TERRAIN Altitude/Color  Correlation
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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. Garmin accurately processes and cross-
validates the data, but cannot guarantee the 
accuracy and completeness of the data. 
The terrain/obstacle databases are contained on a 
datacard which is inserted in the right-most slot of the 
400W Series units. 
Database Versions
The version and area of coverage of each terrain/
obstacle database is shown on the Terrain Data-
base Versions Page, located in the AUX Page Group. 
Databases are checked for integrity at power-up. If a 
database is missing or corrupt, the TERRAIN system 
will fail the self-test and issue a failure message. 
TERRAIN Database Information
Database Updates
Terrain/Obstacle databases are updated periodi-
cally with the latest terrain and obstacle data. Visit the 
Garmin website to check for newer versions of terrain/
obstacle databases. Compare database cycle numbers 
to determine if a newer version is available. 
The database update process includes either 
reprogramming or replacing the database card and 
inserting the updated card in the right card slot on the 
unit front panel. The terrain/obstacle database may 
be downloaded via the intenet and the card repro-
grammed using a USB programmer available from 
Garmin. Contact Garmin at 800-800-1020 or at www.
garmin.com for more information. 
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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 describes the area of coverage avail-
able in each database. Regional definitions may change 
without notice. 
DatabaseCoverage Area
Worldwide (WW)Latitudes:  N 75° to S 60° 
Longitudes: W 180° to E 180° 
United States (US)
Limited to the United States plus 
some areas of Canada, Mexico, 
Caribbean, and the Pacific. 
US/Europe
Alaska, Austria, Belgium, Canada*, 
Caribbean*, Czech Republic, 
Denmark, Estonia, Finland, France, 
Germany, Greece, Hawaii, Iceland, 
Ireland, Italy, Latvia, Lithuania, 
Mexico*, Netherlands, Norway, 
Poland, Portugal, Slovakia, Spain, 
Sweden, Switzerland, United 
Kingdom, United States 
* Indicates partial coverage
 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 necessarily 
charted and therefore may not be contained in 
the Obstacle Database. 
Navigation Database
It is therefore important to also have the latest 
Navigation Database installed to ensure correct Terrain 
alerting. 
TERRAIN Alerts
TERRAIN alerts are issued when flight conditions 
meet parameters that are set within the TERRAIN system 
software algorithms. When an alert is issued, visual 
annunciations are displayed. Annunciations appear in a 
dedicated field in the lower left corner of the display. 
TERRAIN Annunciation and Pop-Up 
Alert
TERRAIN Annunciation  Field TERRAIN  Pop-Up Alert
Pop-up Alerts
On any page except the TERRAIN Page, when a terrain 
or obstacle alert is issued, a pop-up window is displayed 
with the appropriate alert. 
To acknowledge the pop-up alert and return to 
the currently viewed page: 
Press the CLR key. 
To acknowledge the pop-up alert and quickly 
display the TERRAIN Page: 
Press the ENT key. 
Terrain Operation
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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 also provided. 
“TERRAIN ADVISORY” advisory—Similarly, an 
“OBSTACLE ADVISORY” alert is also provided. 
Phase of FlightLevel FlightDescending
En Route700 ft.500 ft.
Terminal350 ft. 300 ft.
Approach150 ft.100 ft.
Departure100 ft.100 ft. 
Minimum Terrain  Clearance Values
 NOTE: During the final approach phase of flight, 
FLTA alerts are automatically inhibited when the 
aircraft is below 200 feet AGL while within 0.5 
NM of the approach runway or is below 125 feet 
AGL while within 1.0 NM of the runway. 
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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
The TERRAIN system continually monitors 
several system-critical items, such as database validity, 
hardware status, and GPS status. Should the system 
detect a failure, a message is annunciated “TERRAIN 
has failed”. 
“TERRAIN has failed” message
Terrain Alerts
700
600
500
400
300
200
100
Height Above Terrain (Feet)
Distance From Destination Airport (nm)
   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15
PDA Alerting Area PDA Alerting Area
Runway
Threshold
Premature  Descent Alerting  (PDA) Threshold
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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
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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 being below minimum clearance values. 
Obstacle FLTA advisory generated by predicted or present 
aircraft altitude being below minimum clearance values. Un-
less there is a change in conditions a OBSTACLE AHEAD alert 
may be generated. 
(FLASHING)(FLASHING)
Obstacle FLTA alert generated by predicted or present aircraft 
altitude being below minimum clearance values. 
PDA alert when the aircraft is significantly below the normal 
approach path to the runway. 
TERRAIN Alerts Summary
Terrain Alerts
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