Section 2 System Overview
2-24
IDU-450 EFIS Software Version 8.0H (Rotorcraft)
1
st
Ed Nov 2018
Table 2-4: Time-Critical Warning and Caution Alerts
Visual Alert
Voice Alert
“--” No Voice Alert
Condition
** No time delay
“Pull Up,
Pull Up”
Within GPWS Mode 1 warning
envelope.
Half-second time delay.
“Terrain, Terrain,
Pull Up, Pull Up”
Within GPWS Mode 2 warning
envelope.
Half-second time delay.
“Glideslope,
Glideslope”
Within GPWS Mode 5 warning
envelope.
Half-second time delay.
“Check Gear, Check
Gear”
Activates if aircraft is below 150’
AGL, is descending, and any
landing gear is not down.
2-second time delay.
“Caution Terrain,
Caution Terrain”
Within GPWS Mode 2 caution.
Terrain cell within TAWS FLTA
caution envelope.
Half-second time delay.
“Sink Rate,
Sink Rate”
Within GPWS Mode 1 caution
envelope.
Half-second time delay.
“Too Low Terrain,
Too Low Terrain”
Within GPWS Mode 3 envelope.
Half-second time delay.
Within GPWS Mode 4-1 “Too
Low Terrain” envelope.
Half-second time delay.
“Too Low Gear, Too
Low Gear”
Within GPWS Mode 4-2 “Too
Low Gear” envelope.
Half-second time delay.
“Glideslope,
Glideslope”
Within GPWS Mode 5 caution
envelope.
Half-second time delay.
“Caution
Obstruction, Caution
Obstruction”
Obstruction within TAWS FLTA
caution envelope.
Half-second time delay.
“Traffic, Traffic”
Not given if own aircraft below
400’ AGL nor if target is below
200’AGL (ground target). **