EGPWS

Question 1

With a predicted terrain conflict: what is the difference between CAUTION &
WARNING alerts?

Answer 1

• Predicted terrain/obstacle collision within 60 secs. vs. 30 secs.
• Appear in AMBER v. RED on the PFD/ND
• Aural alerts do not include “PULL UP” (Caution) v. always include “PULL UP”
  (Warning).

Question 2

If the FMC containing the terrain database is failed, what modes of EGPWS still
function?

Answer 2

1. Excessive sink rate
2. Excessive terrain closure rate
3. Altitude loss after takeoff
4. Gear and or Flaps not in correct config. for landing
5. Descent below glideslope

Question 3

How are the EGPWS Caution QRH procedures different in VMC/daytime vs IMC/night
time conditions?

Answer 3

PF must still correct flight path and/or configuration. In daylight VMC, if positive visual
verification is made that no obstacle or terrain hazard exists prior to any terrain or obstacle
warning – can continue. If night-time or IMC, perform GPWS recovery/escape maneuver.

Question 4

Why should we keep the configuration untouched during EGPWS recovery?

Answer 4

The recovery maneuver must be flown precisely without distractions. Reaching for
gear/flap handle/switches etc. could potentially distract the PF and affect the accuracy of
the maneuver flown.

Question 5

Why shouldn’t we retract the landing gear?

Answer 5

Drag produced by the opening/closing of the gear doors could negatively affect A/C
performance during terrain recovery maneuver.