System Constraints - Honeywell EGPWS MK V Pilot's Manual

Mark V and Mark VII EGPWS Pilot's Guide
System System constraints for the EGPWS are:
Constraints
• If terrain data is unavailable for a particular area, then
• The display of terrain and obstacle information is intended
• If there is no source of aircraft position data meeting the
• TAD/TCF functions should be manually inhibited:
• When the TAD/TCF functions are inhibited and the
• Terrain clearance or descent rates that are not compatible
060-4241-000
Rev H, August 2011
Terrain and Obstacle alerting and display is not available
for that area and the affected display area is colored
MAGENTA (normally only displayed at or near North and
South Poles dependent upon airplane flight path and
location).
to serve as a situational awareness tool. It does not provide
the accuracy and/or fidelity to be the sole source for
deciding terrain or obstacle avoidance. Navigation must not
be predicated upon the use of the EGPWS terrain/Obstacle
display.
accuracy requirements for the TAD and TCF functions,
then these enhanced functions are automatically inhibited
with a resultant Terrain inoperative or unavailable
indication.
• Within 15 nm on approach to an airport or runway that is
not in the airport/runway database to avoid unwanted
alerts.
• During QFE operations if GPS data is unavailable or
inoperative.
EGPWS is otherwise functional, the EGPWS reverts to
providing basic GPWS functions (Modes 1 to 6 and
Windshear). In this state, the EGPWS may give little or no
advance warning time for flight into precipitous terrain
where there are few or no preceding obstructions. This
particularly applies if:
• The aircraft is in the landing configuration.
• The aircraft is in a stabilized descent at a normal
approach descent rate.
• There is no ILS Glideslope signal being received by the
EGPWS (not tuned, not available, or inoperative).
with required minimum regulatory standards for Ground
Proximity Warning equipment may cause unwanted alerts.
Operational Procedure
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