Forward Looking Terrain Avoidance - Garmin GTN 750 Pilot's Manual Upgrade Supplement

Alert Type
Voice Call Out
(VCO-500)
* Alerts with multiple messages are configurable at installation and are
installation-dependent. Alerts for the default configuration are indicated with asterisks.
11.5.6.2

Forward Looking Terrain Avoidance

Reduced Required Terrain Clearance (RTC), Reduced Required Line
Clearance (RLC), and Reduced Required Obstacle Clearance (ROC) alerts
are issued when the aircraft flight path is above terrain, yet is projected to come
within the minimum clearance values in the FLTA Alert Minimum Terrain and
Obstacle Clearance Values table. When an RTC, RLC, and/or a ROC alert is
issued, a threat location indicator is displayed on the Terrain page.
Imminent Terrain Impact (ITI), Imminent Line Impact (ILI), and
Imminent Obstacle Impact (IOI) alerts are issued when the aircraft is below
the elevation of a terrain or obstacle cell in the aircraft' s projected path. ITI, ILI,
and IOI alerts are accompanied by a threat location indicator displayed on the
Terrain page. The alert is annunciated when the projected vertical flight path is
calculated to come within minimum clearance altitudes in the following table.
Flight Phase
En Route
Terminal
Approach
Departure
Table 11-9 FLTA Alert Minimum Terrain and Obstacle Clearance Values
During final approach, FLTA alerts are automatically inhibited when the
aircraft is below 200 feet AGL while within 0.5 NM of the approach runway or
below 125 feet AGL while within 1.0 NM of the runway threshold.
190-01007-03 Rev. Q
Alert
Annunciation
None
Table 11-8 Alerts Summary
Minimum Clearance Altitude (feet)
Level Flight
700
350
150
100
GTN 725/750 Pilot's Guide
Aural Message
"Five-Hundred"
Descending
500
300
100
100
Foreword
Getting
Started
Audio &
Xpdr Ctrl
Com/Nav
FPL
Direct-To
Proc
Charts
Wpt Info
Map
Traffic
Terrain
Weather
Nearest
Services/
Music
Utilities
System
Messages
Symbols
Appendix
11-17
Index