Warning Systems Flashcards
The primary method for alerting the crew to non-normal conditions is
“system alert messages.”
Equipment faults which may affect airplane dispatch capability are shown by
status messages.
The rectangular icon is removed when the checklist is
complete or when inhibited by the checklist of another message.
There are three priority levels with the EICAS alert messages.
These are
warning, caution and advisory level.
The red EICAS alert messages
will always remain displayed and cannot be
cancelled by the flight crew.
Amber EICAS alert messages
can be cancelled and
recalled by pushing the CANC/RCL switch.
Communication alerts are
displayed in white below the alert messages.
The communication alerts cannot
be cancelled by pushing the CANC/RCL switch.
To provide a cross reference
to the item or system for dispatch capability,
all status messages are
listed in the Minimum Equipment List (MEL).
Each successive page can be displayed by pushing the
CANC/RCL switch.
Warning messages are displayed at the top of each page.
There is no page numbering for numerous warning messages.
It is not possible to display other pages
in this situation until the warnings no longer exist.
The most recent EICAS memo message is displayed
at the bottom of the memo messages.
If there are additional status pages, pushing the
STAT button will display each succeeding page.
This works in a similar manner to the CANC/RCL switch.
To display currently displayed engine indications
and additional EICAS
maintenance information,
the EICAS EVENT RCD switch
is pushed.
Up to five events may be recorded by the first five pushes.
When a system parameter is exceeded, the system will automatically
record the out of limit parameters and related conditions.
The siren cannot be silenced until the condition is corrected,
but the master WARNING light is
extinguished by pushing the master WARNING / CAUTION reset switch.
There are some messages associated with the siren that can be silenced ex. Cabin Altitude
Pilot Response
A high-low chime announces a new EICAS
medium-level communication alert.
The respective EICAS warning message CONFIG is displayed if
the airplane is on the ground,
with the FUEL CONTROL switches in the RUN position,
and either engine thrust is in takeoff range,
the thrust reversers are not unlocked or deployed,
and the airspeed is less than V1.
For the warning message CONFIG GEAR STEERING airspeed must be less
than 80 kt.
Takeoff configuration warnings are annunciated for any of the following configurations:
an entry, forward cargo, or aft cargo door is not latched and locked;
flaps not in the takeoff position;
main gear steering not locked;
parking brake set;
rudder trim not centered;
SPEED BRAKE lever not in DOWN detent;
stabilizer trim not in the green band.
he EICAS warning message CONFIG GEAR is displayed if
the airplane is in flight and any landing gear is not down and locked,
with either thrust lever closed and radio altitude less than 800 ft,
or the FLAP lever in the landing position.
o prevent potential conflicts between required maneuvers during alerts,
the three warning systems are prioritized as follows:
Windshear, GPWS and TCAS.
If a GPWS or PWS warning alert occurs
and TA/RA has been selected
on the transponder,
the RA mode will
automatically be inhibited.
All RA aircraft will now be shown as TA aircraft.
When the GPWS and PWS warning alerts are no longer in effect,
the RA mode inhibit will end.
Certain EICAS alert messages are time delayed,
even though
related flight deck panel annunciator lights are illuminated.
Automatic display of new TCAS warnings,
EGPWS/GPWS terrain alerts or PWS alerts are
inhibited in the event of an immediate windshear alert.
If a new EGPWS / GPWS terrain alert occurs when both NDs
are in MAP, MAP CTR, VOR, or APP mode,
TERR will be automatically selected for both NDs.
If a new EGPWS/GPWS terrain alert occurs and only one ND is
in MAP, MAP CTR, VOR, or APP mode,
TERR will be automatically selected for that ND.
If a new PWS occurs
when both ND’s are in
MAP, MAP CTR, VOR, or APP mode,
the WXR is automatically selected for both ND’s.
If a new PWS alert occurs when only one ND
is in MAP, MAP CTR, VOR, or APP mode,
the WXR is automatically selected for that ND.
While on the ground and with both FUEL CONTROL switches in CUTOFF,
the beeper and master CAUTION lights
are inhibited for all EICAS messages.
During engine start,
all new EICAS caution and advisory messages are inhibited,
except those listed here.
The inhibit begins when
the engine START/IGNITION selector is moved to START
and ends when the engine reaches idle RPM,
or the start is aborted, or five minutes elapse.
TCAS TA voice alerts for TCAS TAs are inhibited below
500 ft.
TCAS CLIMB RAs are inhibited until approximately
1,100 ft AGL (climb) and 900 ft AGL (descent).
TCAS DESCEND RAs are inhibited for
T/O until 1,100 ft RA and below 1,100 ft RA during landing.
The STATUS cue is inhibited
for all EICAS status messages
from engine start to 30 minutes after lift-off.
From the time either engine is advanced to takeoff thrust
through 400 feet RA or until 20 seconds after rotation,
all EICAS communication messages
(except CABIN ALERT and the aural chime) are inhibited.
The master CAUTION lights and beeper are inhibited
for new EICAS caution messages displayed during the inhibit period,
which begins at 80 kt airspeed and ends at 400 ft Radio Altitude or 20 seconds
after lift-off, whichever occurs first.
If a rejected takeoff is initiated above 80 kt, the inhibit continues
until the airspeed is less than 75 kt.
If the master CAUTION lights illuminate before reaching 80 kt airspeed,
they continue to be illuminated when 80 kt airspeed is exceeded
and cannot be extinguished until the inhibit ends.
All EICAS advisory messages are inhibited from 80 kt airspeed
until 400 ft Radio Altitude or 20 seconds after lift-off,
whichever occurs first, or
if takeoff thrust is not selected on both engines.
The master WARNING lights and fire bell are inhibited at V1
until one of the following, whichever occurs first;
400 ft Radio Altitude or 25 seconds after V1.
If the master WARNING lights illuminate and the fire bell sounds before reaching V1,
they continue to be illuminated and sound when V1 is exceeded.
New PWS caution alerts are inhibited from
New PWS warning alerts are inhibited from
80 kt airspeed to 400 ft Radio Altitude.
100 kt airspeed to 50 ft Radio Altitude.
EICAS takeoff configuration warnings are inhibited
when airspeed exceeds V1.
All PWS alerts are inhibited from 1,200 ft Radio Altitude on takeoff
until on approach.
All PWS alerts are inhibited from
T
2,300 ft Radio Altitude down to 1,200 ft Radio Altitude.
All EICAS communication messages, except CABIN ALERT,
are inhibited from
800 ft Radio Altitude until 75 kt airspeed on landing.
The STATUS cue for all EICAS status messages is inhibited from
800 ft Radio Altitude until 75 kt airspeed on landing.
The EICAS alert message WINDSHEAR SYS is inhibited from
400 ft Radio Altitude to 80 kt airspeed on landing.
New PWS caution alerts are inhibited below
400 feet Radio Altitude.
New PWS warning alerts are inhibited below
50 ft Radio Altitude.
When LAND 2 or LAND 3 is displayed on the PFD
and the aircraft is at 200 ft Radio Altitude on approach,
the master CAUTION lights and beeper
are inhibited for all EICAS caution messages,
except
AUTOPILOT,
AUTOTHROTTLE DISC,
NO AUTOLAND
and SPEEDBRAKE EXTENDED.
The inhibit ends at 75 kt airspeed on landing,
or when 40 seconds have elapsed,
or at 800 ft Radio Altitude on go-around.
Failure of the EGPWS terrain functions
will not affect the operation of the basic GPWS functions.
If the GPS position is lost,
EGPWS capabilities are also lost.
With the terrain function enabled (OVRD not selected),
an automatic pop-up display feature provides
automatic display of terrain for both pilots if
an alert occurs and neither pilot has the terrain display selected.
The display will remain until the following occurs:
the threat no longer exists,
or the TERR switch is manually deselected.
When the terrain display is selected to the ND,
terrain is depicted as variable density dot patterns in
green, amber, and red. Magenta will be shown in areas of
the world where terrain data is not available.
Note that although no antennas are associated with the EGPWS,
the terrain display is generated from
the radar display bus.
Therefore, a sweep is built into the display.
The Ground Proximity Warning System (GPWS) is distinct from the EGPWS previously discussed.
Below 2,450 feet the GPWS provides
immediate alerts for potentially hazardous
flight conditions involving imminent impact
with obstacles and the ground.
GPWS immediate alerts are based on
Radio Altitude,
Barometric Altitude,
ADIRS,
glideslope deviation,
and airplane configuration.
A GPWS caution or warning does not necessarily guarantee
obstacle or terrain clearance
as some obstacles or terrain
ahead of the airplane
may exceed the available climb performance.
When the airplane is higher than 2,000 ft
above the terrain, obstacles and terrain peaks are displayed
using solid, high density,
and low density contours of green.
When an OBSTACLE alert occurs
while a TERRAIN alert message is displayed,
the OBSTACLE alert message
replaces the TERRAIN alert message.
Both messages will not be displayed at the same time.
When the aircraft is 40 to 60 sec from projected impact with terrain,
the voice annunciation
CAUTION TERRAIN, CAUTION TERRAIN sounds.
When the aircraft is 20 to 30 sec from projected impact with terrain,
the voice annunciation TERRAIN, TERRAIN, PULL UP, PULL UP sounds.
GPWS windshear detection begins at rotation and is enabled
while the aircraft is below 1,500 ft Radio Altitude.
In flight with the WXR switch pushed or not pushed,
the weather radar begins scanning
for windshear below 2,300 ft radio altitude
and PWS alerts are enabled below
1,200 ft radio altitude.
The advisory message CONFIG WARNING SYS indicates
that a fault has been detected in the configuration warning system.
Radio altitude voice callouts and other aural alerts may not be available.
The advisory message GND PROX SYS indicates
some or all ground proximity alerts may not be provided.
Ground proximity alerts which occur are valid.
The advisory message TERR POS indicates position data for the ND terrain
map and look-ahead terrain alerts have been lost.
Ground proximity alerts which occur
are valid.
