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Part Three: Section 2
TAWS Alerts
Section 3: TAWS Alerts
Alerts are issued when flight conditions meet
parameters that are set within TAWS software
algorithms. TAWS alerts typically employ either a
CAUTION
or a
WARNING
alert severity level, or
both. When an alert is issued, visual annunciations
are displayed. Aural alerts are simultaneously issued.
Annunciations appear in a dedicated field in the lower
left corner of the display.
TAWS Annunciation Field
TAWS Annunciation Field
Annunciations are color-coded according to the
TAWS Alert Summary table. Pop-up terrain alerts can
also appear during an alert, but
only when the TAWS
Page is not displayed
. There are two options when
an alert is displayed:
To acknowledge the pop-up alert and return to
the currently viewed page:
Press the
CLR
button.
To acknowledge the pop-up alert and quickly
access the TAWS Page:
Press the
ENT
button.
NOTE:
To further capture the attention of the pilot,
TAWS issues aural (voice) messages that accompany
visual annunciations and pop-up alerts. Some aural
messages are configurable during installation of the
system. For a summary of aural messages, see the
TAWS Alert Summary table.
NOTE:
TAWS Caution Alerts are displayed as constant
black text on a yellow background; TAWS Warning
Alerts are displayed as constant white text on a red
background.
Forward Looking Terrain Avoidance
The unit will issue terrain alerts not only when the
aircraft altitude is below the terrain elevation but
also when the aircraft is projected to come within
minimum clearance values of the terrain. This
alerting, called Forward Looking Terrain Avoidance
(FLTA), is also provided for obstacles. Any potential
impact points are depicted on the display. There
are 2 levels of severity for FLTA alerts. They are
cautionary (amber) and warning (red) in nature and
are described in further detail below.
CAUTION—Estimated potential impact in approximately 30 sec-
onds after a FLTA Caution pop-up alert and annunciation. FLTA
caution alerts are accompanied by the aural message “
Caution
Terrain; Caution Terrain
” OR “
Terrain Ahead; Terrain Ahead
”.
Similarly, a
“Caution Obstacle; Caution Obstacle”
or
“Obstacle
Ahead; Obstacle Ahead”
alert is also provided. The time to an
alert can vary with conditions, therefore there is no guarantee
of a 30 second caution alert being issued.
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