Beechcraft C-12C Operator And Technical Reference Manual page 560

TM 1-1520-218-10
climb, or whenever the aircraft is out of the operating
altitude range of the radio altimeter.
(2) Hundred Foot Increment Aural Altitude
Advisories (Mode 2).
Thousand, Nine Hundred, Eight Hundred, Seven
Hundred, Six Hundred, Five Hundred, Four Hundred,
Three Hundred, Two Hundred, One Hundred" indicate
that the aircraft is at the associated radio altitude in
feet AGL. This advisory is cancelled when valid
information from the radio altimeter is lost, during
climb, or whenever the aircraft is out of the operating
altitude range of the radio altimeter.
(3) Aural "Localizer" Advisory (Mode 3). The
aural advisory "Localizer" indicates that the aircraft has
deviated from the center of the localizer beam in
excess of 1.3 to 1.5 dots. The localizer advisory is
armed when a valid localizer signal is detected and the
aircraft is below 1000 feet AGL. It will be repeated no
more that three times at 4-second intervals unless the
aircraft is returned to less than 1.3 to 1.5 dots from the
center of the localizer course. The localizer advisory is
disabled when a valid localizer signal has been lost,
during climb, below the decision height set on the
radio altimeter, or if the navigation receiver is not
tuned to a localizer frequency.
(4) Aural "Check Gear" Advisory (Mode 4).
The aural "Check Gear" advisory indicates that the
aircraft has descended to 500 feet AGL and the
landing gear is not down. This advisory is repeated
once at 100-foot intervals down to 100 feet AGL.
(5) Aural "Glideslope" Advisory (Mode 5).
The aural advisory "Glideslope" indicates that the
aircraft has exceeded 1.3 to 1.5 dots above or below
the center of the glideslope beam.
advisory is armed when a valid glideslope signal is
detected and the aircraft is below 1000 feet AGL. It
will be repeated no more than three times at 4-second
intervals unless the aircraft is returned to less than 1.3
to 1.5 dots from the center of the beam.
glideslope advisory is disabled upon loss of a valid
glideslope signal, during climb, on a localizer back
course, below the decision height set on the radio
altimeter or, if the navigation receiver is not tuned to a
localizer frequency. This advisory is inhibited by the
weight on wheels strut switch.
(6) Aural Advisory
(Mode 6). The aural advisory "Minimum, Minimum"
indicates that the aircraft is at the radio altitude
selected by the crew using the radio altimeter indicator
DH knob. This advisory is cancelled when valid
information from the radio altimeter is lost, during
climb, whenever the aircraft is above 1000 feet AGL,
3C-206
The aural advisories "One
The glideslope
"Minimum, Minimum"
or whenever the aircraft is out of the operating altitude
range of the radio altimeter.
(7) Aural
(Mode 7). The aural advisory "Altitude, Altitude"
indicates the approach to a pre-selected altitude as the
aircraft reaches a point 1000 feet from the selected
altitude or, after reaching the selected altitude, when
the aircraft deviates more than 250 feet from the
selected altitude.
(8) Aural "Check Trim, Check Trim, Check
Trim" Advisory.
Check Trim, Check Trim" indicates that the autopilot
has had a trim failure.
(9) Aural "Autopilot" Advisory.
advisory "Autopilot" indicates that the autopilot has
disengaged.
d. Emergency Procedures. If an emergency
or malfunction makes it necessary to disable the
GPAAS, pull the GPAAS POWER circuit breaker
located on the instrument panel. GPAAS audio may
be turned off by pressing the VOICE OFF switch.
3C-32. TRAFFIC
AVOIDANCE SYSTEM (TCAS II).
a. System Overview.
(1) The Traffic Alert and Collision Avoidance
System is an airborne system that interrogates mode
A/C and mode S transponders in nearby aircraft and
uses the replies to identify and display potential and
predicted collision threats to the flight crew.
system protects a volume of air space around your
own aircraft. Aural and visual advisories are provided
to the flight crew to assure adequate separation when
a system analysis of the intruding aircraft closure rate,
derived from
penetration of the protected airspace. The TCAS II is
The
controlled through the TTC-920 Transponder/TCAS
control panel located on the pedestal.
(2) Traffic alerts and resolution advisories
are indicated on the TVI-920 Transponder/TCAS
Display. Traffic alerts provide the flight crew with the
relative bearing and distance to intruding aircraft that
are approximately 40 seconds from Closest Point of
Approach (CPA). This alert provides aid in visually
acquiring the intruding aircraft.
commanded. The resolution advisory provides threat
resolution information in the form of a vertical
maneuver (corrective) or restricted vertical speed
range (preventive) that will increase aircraft separation
when the threat aircraft is approximately 25 seconds
from CPA.
"Altitude, Altitude"
The aural advisory "Check Trim,
ALERT AND
transponder replies,
No maneuvers are
Advisory
The aural
COLLISION
The
predicts a