GNS 530(A) Pilot’s Guide and Reference
190-00181-00 Rev. E 12-3

SECTION 12

TERRAIN
12.2 TERRAIN PAGE
See Section 3.5 for a complete description of the
TERRAIN Page and its operation.

TERRAIN Symbols

The symbols and colors in Figure 12-1 and Table

12-1 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 12-1 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 12-1 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.