GPS 400 Pilot’s Guide and Reference
190-00140-60 Rev. E
9-3
SECTION 9
TERRAIN
9.2 TERRAIN PAGE
See Section 2.5 for a complete description of the
TERRAIN Page and its operation.
TERRAIN Symbols
The symbols and colors in Figure 9-1 and Table
9-1 are used to represent obstacles and potential
impact points on the TERRAIN Page. TERRAIN
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 annunciations also use
these color assignments.
Potential Impact Point
Unlighted Obstacle
Projected Flight Path
1000 ft
100 ft Threshold
Terrain more than 1000 ft below the aircraft altitude (Black)
Terrain between 100 ft and 1000 ft below the
aircraft altitude (Yellow)
Terrain above or
within 100 ft
below the aircraft
altitude (Red)
Figure 9-1 Terrain Altitude/Color Correlation
Unlighted Obstacle
Lighted Obstacle
Potential
Impact
Points
Obstacle Location
Alert Level
< 1000’
AGL
> 1000’
AGL
< 1000’
AGL
> 1000’
AGL
Obstacle Symbol
Obstacle above or within
100’ below current aircraft
altitude
WARNING
(Red)
Obstacle between 100’ and
1000’ below current aircraft
altitude
CAUTION
(Yellow)
Table 9-1 Terrain/Obstacle Colors and Symbology
NOTE: If an obstacle and the projected flight path
of the aircraft intersect, the display automatically
zooms in to the closest potential point of impact
on the TERRAIN Page.
