Garmin G1000 NXi Pilot’s Guide for the Cessna NAV III
190-02177-02 Rev. A
SY
STEM
O
VER
VIEW
FLIGHT
INSTRUMENTS
EIS
AUDIO P
ANEL
& CNS
FLIGHT
MANA
GEMENT
HAZARD
AV
OID
ANCE
AFCS
ADDITIONAL FEA
TURES
APPENDICES
INDEX
324
HAZARD AVOIDANCE
FORWARD LOOKING TERRAIN AVOIDANCE
The Forward Looking Terrain Avoidance (FLTA) feature of Terrain-SVT or TAWS-B compares the projected
flight path as derived from GPS data with terrain features and obstacles from the terrain and obstacle databases.
The system issues FLTA alerts when the projected flight path conflicts with terrain or obstacles.
The projected flight path is a calculated area ahead of, to the sides, and below the aircraft. The size of the
projected flight path varies based on factors including ground speed (the path ahead is larger when the ground
speed is higher), whether the aircraft is level, turning, or descending, and the proximity to the nearest runway
along the current track. As the aircraft approaches the runway, the projected flight path becomes narrower until
the system automatically disables FLTA alerts or the pilot manually inhibits them.
There are two types of FLTA alerts, Reduced Required Terrain/Obstacle/Line Clearance (RTC /ROC/RLC
respectively) and Imminent Terrain/Obstacle/Line Impact (ITI/IOI/ILI respectively).
0
100
200
300
400
500
600
700
800
0
5
10
15
20
25
30
Re
qu
ire
d T
er
ra
in
Cle
ar
an
ce
(F
T)
Level (FT)
Descending (FT)
Figure 6-68 FLTA Alert Minimum Terrain and Obstacle Clearance Values
Distance From Runway (NM)
Required Clear
ance (FT)
The system automatically disables FLTA alerts when the aircraft is less than 200 feet above the destination
runway elevation while within 0.5 nm of the approach runway or the aircraft is between runway ends.
ADDITIONAL TAWS-B ALERTING
In addition to the FLTA alerting discussed previously, TAWS-B provides the following additional types of
alerts.
EXCESSIVE DESCENT RATE ALERT
The purpose of the
Excessive Descent Rate (EDR)
alert is to provide notification when the aircraft is
determined to be closing (descending) upon terrain a rate that is calculated to be excessive relative to height
above terrain. The following figure shows the parameters for the alert.