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Section 8 Terrain Awareness Warning System
1
st
Ed Nov 2018
IDU-450 EFIS Software Version 8.0H (Rotorcraft)
8-9
Table 8-5: HTAWS GPWS Mode 2A Envelopes (NOT in Landing
Configuration)
AGL
Rate
(fpm)
AGL Altitude (ft
.
)
Caution
Threshold
Warning
Threshold
1905
125%
AGL Rate
1600
66%
Caution
Threshold
1905
20% of the lesser of:
Airspeed
KIAS
AGL Rate
fpm
90
3120
90 to 130
3120
72
Airspeed
90
130
6000
or
AGL Rate
Table 8-6: HTAWS GPWS Mode 2B Envelopes (Landing
Configuration)
AGL Altitude (ft
.
)
Caution Threshold
Warning Threshold
Lesser of:
300 or
20%
AGL Rate
2000
66%
Caution Threshold