Honeywell EGPWS MK VII - Page 47

Mark V and Mark VII EGPWS Pilot’s Guide
060-4241-000 System Description
Rev H, August 2011 41
Radio
Altitude
Continued
This is only performed if TAD is enabled, high integrity
terrain and position data is available (based on GPS/
Geometric Altitude), and the Computed Terrain Clearance is
greater than 4000 feet (2500 feet with version -218-218 or
later). This feature reduces the potential for nuisance alerts
caused by false tracking of the Radio Altimeter.
FMS, IRS,
AHRS
Pitch and Roll Attitude, Latitude and Longitude Position,
Body Normal and Longitudinal Accelerations, Magnetic and
True Track Angles, Magnetic and True Heading, Inertial
Altitude, Groundspeed, and Attitude Mode.
Global
Positioning
System
(GPS)
Latitude and Longitude Position, True Track Angle, GPS
Altitude, Groundspeed, Horizontal and Vertical Figure of
Merit (VFOM/HFOM), Horizontal and Vertical Dilution of
Precision (HDOP/VDOP), Horizontal Integrity Limit (HIL),
and sensor status.
Note: Runway Awareness and Advisory System (RAAS),
Stabilized Approach Monitor,
Takeoff Flap Configuration
Monitor, and Long Landing monitor functions require a GPS
source capable of providing Latitude (fine) and Longitude
(fine) data.
VHF Nav
Receiver
Glideslope, Localizer, ILS Tuned, Selected Runway Heading.
Terrain
Display
System
Display range, and if available the Hazard Bus from a
Predictive Windshear System (PWS). If EFIS, the EFIS
display mode is used in some configurations.
AOA Vane or
Stall Warning
Discretes
AOA, Stick Shaker Margin.
Discrete inputs are used for system configuration,
signal/status input, and control input functions.
EGPWS program pins are utilized to tell the system the type
of aircraft and interface that it is in. These are defined and
established during the EGPWS installation. EGPWS output
functions are consequently the result of the program pin state
read each time the EGPWS is powered on.
Signal/status discretes include signals suc
h as Decision
Height, Landing Flaps selected or Flap Position discretes,
Landing Gear selected, Terrain Display Range, and status
discretes such as Glideslope Valid, Localizer Valid, Radio
Altitude Valid associated with analog signal inputs.
Control discre
tes control EGPWS functions. These include
EGPWS Test, Glideslope Cancel, Glideslope Inhibit or
Glideslope Backcourse, Terrain (display) select, Terrain Inhibit,
Flap Override, Audio Inhibit, Altitude Callout Enable, Steep
Approach Enable, and ILS Tuned discretes.