User Guide

190-00592-02 Rev. A
Garmin G1000 Pilot’s Guide for the Diamond DA40/40F
6-45
HAZARD AVOIDANCE
PREMATURE DESCENT ALERTING
A Premature Descent Alert (PDA) is issued when the system detects that the aircraft is significantly below
the normal approach path to a runway (Figure 6-56).
PDA alerting begins when the aircraft is within 15 nm of the destination airport and ends when the aircraft
is either 0.5 nm from the runway threshold OR is at an altitude of 125 feet AGL while within 1.0 nm of the
threshold. During the final descent, algorithms will set a threshold for alerting based on speed, distance, and
other parameters.
Figure 6-50 PDA Alerting Threshold
EXCESSIVE DESCENT RATE ALERT
The purpose of the Excessive Descent Rate (EDR) alert is to provide suitable notification when the aircraft is
determined to be closing (descending) upon terrain at an excessive speed. Figure 6-57 shows the parameters
for the alert as defined by TSO-C151b.
5000
4500
4000
3500
3000
2500
2000
1500
1000
500
0
2000 4000 6000 8000 10000 12000
"PULL UP""
P
U
L
L
U
P
"
"
S
I
N
K
R
A
T
E
"
Descent Rate (FPM)
Height Above Terrain (Feet)
Figure 6-51 Excessive Descent Rate Alert Criteria