TM 55-1510-219-10
to INS circuits. It is dedicated only to updating the INS,
is activated when the INS is operational, and is
controlled only by the INS. The INS TACAN consists of
a range unit and a distance indicator, both located on
the INS equipment rack and both identical to their
counterparts in the avionics TACAN, and an antenna
located on the underside of the fuselage. No controls
are required or provided for the INS TACAN system.
The system is protected by a circuit breaker on the INS
junction box.
d.
Controls and Indicators.
CONTROL/
FUNCTION
INDICATOR
TEST switch
Activates system self-test.
Channel
Displays TACAN channel select-
indicator
ed.
X-Y switch
Selects X or Y mode for TA-
CAN channels.
VOL control
Adjusts TACAN volume.
Channel
Dual knob for manual selection
selectors
of operating channel.
Outer knob
Selects tens and hundreds part
of channel number.
Inner knob
Selects units part of channel
number.
ON-OFF switch
Activates or deactivates system.
NM indicator
Displays slant range distance in
nautical miles from aircraft to
selected TACAN ground station.
KT indicator
Displays ground speed in knots.
MIN indicator
Displays time to TACAN station
in minutes.
e.
Avionics TACAN Operation.
(1)
Turn-On.
1. ON-OFF switch (TACAN panel) ON.
2. VOL knob As required.
3. Course
indicator
switches
(instrument panel) -Select TACAN.
NOTE
The pilot and copilot should not
select TACAN simultaneously for
test.
(2)
Normal operation.
1. Pilot's
single
needle
switch
VOR/TACAN.
Figure 3-17. TACAN Control Panel and Range Indicator (ID-2218)
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