Pilot's Operating Handbook
Supplement 49
GARMIN TAWS system
Edition 2 - December 31, 2015
Rev. 2
Page 9.49.10
2. Premature descent alerting
A Premature Descent Alert (PDA) is issued when the system detects that the airplane
is significantly below the normal approach path to a runway (Figure 9.49.1).
PDA alerting begins when the airplane is within 15 Nm of the destination airport. PDA
alerting ends when the airplane is either :
-
0.5 Nm from the runway threshold
or
-
at an altitude of 125 feet AGL while within 1.0 Nm of the threshold.
Figure 9.49.1 - PDA alerting threshold
PDA Alerting Area
The aural/displayed messages associated with the PDA function are described in the
table 9.49.3.
Alert Type
PFD/MFD
TAWS Page
Annunciation
MFD Map Page
Pop-Up Alert
Aural Message
Premature Descent
Alert Caution
(PDA) (Amber)
TERRAIN
TOO LOW - TERRAIN
”Too low, Terrain”
Table 9.49.3 - PDA alerts
PIM - DO NOT USE FOR FLIGHT OPERATIONS
