Cockpit Reference Guide

Garmin G1000 Cockpit Reference Guide for the Cessna Nav III
190-00384-11 Rev. A
10-15
SECTION 10 – HAZARD
AVOIDANCE
Terrain Inhibit
Flying VFR into an area where unique terrain exists
could cause the system to annunciate a nuisance alert.
Inhibit TERRAIN-SVS:
While the TERRAIN-SVS Page is displayed, press
the INHIBIT Softkey. ‘TER INHB’ is annunciated in
the lower right of portion of the screen.
Enable TERRAIN-SVS:
If TERRAIN-SVS has been inhibited, from the
TERRAIN-SVS Page press the INHIBIT Softkey. The
‘TER INHB” annunciation is removed.
NOTE: If TERRAIN-SVS alerts are inhibited when
the Final Approach Fix is the active waypoint in
a GPS WAAS approach, a LOW ALT annunciation
may appear on the PFD next to the altimeter if the
current aircraft altitude is at least 164 feet below
the prescribed altitude at the Final Approach Fix.
Forward Looking Terrain Avoidance (FLTA)
The Forward Looking Terrain Avoidance alert is
composed of two sub-functions:
Reduced Required Terrain Clearance (RTC) and
Reduced Required Obstacle Clearance (ROC)
This provides alerts when the aircraft flight path
is above terrain and/or obstacles, yet is projected to
come within minimum clearance values outlined in the
following table.
Unlighted Obstacle
(Height is less than
1000’ AGL)
Lighted Obstacle
(Height is less than
1000’ AGL)
Unlighted Obstacle
(Height is greater than
1000’ AGL)
Lighted Obstacle
(Height is greater than
1000’ AGL)
Potential Impact Points
Figure 10-23 Terrain-SVS Symbols
Reduced Required Terrain Clearance (RTC) and
Reduced Required Obstacle Clearance (ROC)
This provides alerts when the aircraft flight path is
above terrain and/or obstacles, yet is projected to come
within minimum clearance values outlined in the following
table. When an RTC or ROC alert is issued, a potential
impact point is displayed on the TERRAIN-SVS Page as a
yellow or red ‘X’.
Imminent Terrain Impact (ITI) and Imminent
Obstacle Impact (IOI)
This provides alerts when the aircraft is below the
elevation of terrain in the aircraft’s projected path. ITI and
IOI alerts are accompanied by a potential impact point
displayed on the TERRAIN-SVS Page as a yellow or red
‘X’. The alert is given when the projected vertical flight
path is calculated to come within minimum clearance
altitudes in the following table.
Phase of Flight Level Flight Descending
Enroute 700 ft. 500 ft.
Terminal 350 ft. 300 ft.
Approach 150 ft. 100 ft.
Departure 100 ft. 100 ft.
During the final approach phase of flight, RTC/ROC/
ITI/IOI 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 nm of the
runway.