TM 55-1510-220-10
Figure 3-11. Pilot's Horizontal Situation Indicator (331A-8G)
(3)
RMI select switch. Selects which of two
signals will be displayed on respective RMI single-needle
pointer, if single-needle switch is in the VOR-TACAN
position.
(a)
VOR 1. Selects VOR 1 bearing signals
for display.
(b)
TACAN. Selects TACAN bearing
signal for display.
c.
Indicators and Functions, RMI.
(1)
Double needle pointer. Indicates bearing
selected by double needle switch.
(2)
Compass card. Indicates aircraft heading at
top of dial.
(3)
Heading index. Reference point for aircraft
heading.
(4)
Warning flag. Indicates loss of compass
signal.
(5)
Double needle switch. Selects desired signal
to be displayed by double needle pointer.
(a)
ADF.
Selects
ADF
bearing
information.
(b)
VOR.
Selects
VOR
2
bearing
information.
(6)
Single needle pointer. Indicates bearing
selected by single needle switch.
(7)
Single needle switch. Selects desired signal to
be displayed on single needle pointer .
(a)
INS. Selects INS bearing to waypoint
position.
(b)
VOR-TACAN.
Selects
signal
as
determined by the RMI select switch on the instrument panel,
either VOR No. I or TACAN.
3-19. HORIZONTAL SITUATION INDICATORS.
a.
Description. The pilot and copilot have separate
HSI instruments on respective instrument panel sections (fig.
3-11 and 3-12). Each HSI combines displays to provide a
map-like presentation of the aircraft position. Each indicator
displays aircraft
Change 2
3-22
