The aural message is enunciated twice for each 20%
degradation in altitude. Upon establishing a positive rate of
climb, the EGPWS caution lights extinguish and the aural
alert will cease.
If the Aural Declutter feature is disabled, the warning is
enunciated continuously until positive climb is established.
Mode 4 provides alerts for insufficient terrain clearance with
respect to phase of flight, configuration, and speed. Mode 4
exists in three forms, 4A, 4B, and 4C.
• Mode 4A is active during cruise and approach with the gear
• Mode 4B is active during cruise and approach with the gear
• Mode 4C is active during the takeoff phase of flight with
Mode 4 alerts activate the EGPWS caution lights and aural
To reduce nuisance alerts caused by over-flying another
aircraft, the upper limit of the Mode 4A/B alerting curve can
be reduced (from 1000) to 800 feet. This occurs if the airplane
is above 250 knots with gear and flaps not in landing
configuration and a sudden change in Radio Altitude is
detected. This is intended to eliminate nuisance alerts while
flying a holding pattern and an aircraft over-flight occurs
(with 1000 foot separation).
With version -210-210 and later models, Mode 4 airspeed
expansion is disabled (upper limit held at lowest airspeed
limit) when the Terrain Alerting and Display (TAD) function
is enabled and available. This is due to the enhanced alerting
capability provided with TAD, resulting from high integrity
GPS Altitude and Geometric Altitude data. This change to the
Mode 4 envelopes reduces the potential for nuisance alerts
when the aircraft is not in the landing configuration.
Mode 4A is active during cruise and approach with gear and
flaps up. This provides alerting during cruise for inadvertent
flight into terrain where terrain is not rising significantly, or
the aircraft is not descending excessively. It also provides
alerting for protection against an unintentional gear-up
and flaps not in the landing configuration.
in the landing configuration and flaps not in the landing
either the gear or flaps not in the landing configuration.
Mark V and Mark VII EGPWS Pilot's Guide
Rev H, August 2011