• If enabled, the EGPWS uses onboard measurement of air
• The EGPWS terrain/obstacle database includes cataloged
Refer to an appropriate AFM or EGPWS AFMS for specific
system limitations and procedures.
The EGPWS is fully active when the following systems are
powered and functioning normally:
• Radio Altimeter
• Air Data
• ILS or Glideslope Receiver
• IRS, AHRS, VG (attitude)
• GPS, FMS, or IRS (position)
• Landing gear
• Landing flaps
• Stall warning or AOA (windshear only)
• Weather Radar, EFIS, or a dedicated terrain display
In the event that required data for a particular function is not
available, then that function is automatically inhibited and
annunciated (e.g., if position data is not available or
determined unacceptable, TAD and TCF is inhibited, any
active terrain display is removed, and "TERR INOP", "TERR
UNAVAIL" (or equivalent) is indicated).
Some installations utilize redundant systems so that if the
primary source of data fails, the EGPWS continues on the
EGPWS status annunciations are provided for GPWS
inoperative (mode 1-6 functions), Terrain inoperative
(TAD/TCF functions), and windshear inoperative.
RAAS status messages are provided on the dedicated Terrain
display and can be configured to be shown on a separate
mass parameters and aircraft acceleration for detection of
windshear. This is a reactive system and cannot predict
windshear, which may be ahead of the aircraft.
man-made obstructions 100 feet high or greater within
North America and portions of Europe, Asia and the
Caribbean. The database is not all-inclusive and newer,
smaller, or unknown obstructions could be encountered.
(if terrain/obstacle display enabled)
Mark V and Mark VII EGPWS Pilot's Guide
Rev H, August 2011