Honeywell MK VIII Pilot's Guide

060-4314-000 • Rev. C - May 2004
MK VI & MK VIII EGPWS Pilot Guide
41
Air Data
Radio
Altitude
System
Inputs
The EGPWS uses various input signals from other on-board
systems. The full complement of these other systems is depen-
dent on the EGPWS configuration and options selected. Systems
providing Altitude, Airspeed, Attitude, Glideslope, and position
are required for basic and enhanced functions. Inputs are also
required for discrete signal and control input.
The EGPWS utilizes signals from the following systems:
Uncorrected and corrected Barometric Altitude, Altitude rate,
Computed Airspeed, and Static Air Temperature are provided by
an Air Data system.
Radio Altitude is provided by a Radio Altimeter system. Decision
Height is provided by a Radio Altimeter system or sub-system.
The EGPWS performs Radio Altitude reasonableness checks based
on the Computed Terrain Clearance (pseudo-radio altitude).
Computed Terrain Clearance is computed by subtracting the ele
-
vation of the (database) terrain below the aircraft from Geometric
Altitude (ASL). Radio Altitude is considered unreasonable when
it indicates a terrain clearance that is less than the Computed
Terrain Clearance by more than 2000 feet. For example, if the
Computed Terrain Clearance is 10,000 feet and the Radio Alti
-
tude is any value (0-2500) then the Radio Altitude is considered
unreasonable. This is only performed if TAD is enabled, high
integrity terrain and position data is available (based on GPS/Geo
-
metric Altitude), and the Computed Terrain Clearance is greater
than 4000 feet (2500 feet with version -022 or later).
This feature reduces the potential for nuisance alerts caused by
false tracking of the Radio Altimeter.
FLIGHT DECK
SPEAKERS AN
D
INTERPHONE
ALERT LAMPS
OR EFI
S
DISPLA
Y
EFIS NAV.
DISPLAY OR Wx
RADAR
INDICATOR
AUDIO ALERT
MESSAGES
VISUAL ALER
T
MESSAGES
TERRAIN DISPLA
Y
DATA
AIRCRAFT
PARAMETERS
AIRCRAFT
SENSORS
AND
SYSTEMS
EGPWC
GPWS
ALGORITHM
S
AURAL
CALLOUTS
TERRAIN
AWARENESS
&
OBSTACLE
ALERTING AND
DISPLA
Y
ALGORITHM
S
TERRAIN
CLEARANCE
FLOO
R
ALGORITHM
S
WINDSHEA
R
DETECTION
AND ALERTING
ALGORITHMS
I
N
P
U
T
P
R
O
C
E
S
S
I
N
G
O
U
T
P
U
T
P
R
O
C
E
S
S
I
N
G
CONTROL/
DISCRETS
INPUTS

Honeywell MK VIII Specifications

General

Brand	Honeywell
Model	MK VIII
Category	Security System
Language	English