TM 55-1510-219-10
lamp remains illuminated until
NAV mode is selected.
Lamp lights momentarily during
alignment, if alignment accom-
plished while in NAV mode.
(2)
INS control display unit 6fig. 3-23).
CONTROL
FUNCTIONS
INDICATOR
HOLD key
Used with other CDU controls
to stop present position display
from changing, in order to up-
date position and to display re-
corded malfunction codes.
Lights when pressed first time;
goes out when pressed second
time or when inserted data is ac-
cepted by computer.
When pressed second time, al-
lows displays to resume showing
changing current present posi-
tion.
ROLL LIM key
Allows selection of Limited Roll
steering mode. Press to select
mode, key lights. Roll steering
output is limited to 10 degrees.
Press second time to exit mode,
key light extinguishes. Roll steer-
ing output returns to normal
limit of 25 degrees.
Data display, left
Composed of lamps which illu-
and right
minate to display numbers, deci-
mal points, degree symbols, left
and right directions, and latitude
or longitude directions.
INSERT/
Allows insertion of loaded data
ADVANCE/ HI
into computer. Enters displayed
PREC key
data into INS. When pressed be-
fore pressing any numerical key,
alternates display of normal and
high precision data.
ALERT lamp
Illuminates amber to alert pilot
1.3 minutes before impending
automatic course leg change. Ex-
tinguishes when switched to new
leg, if AUTO/MAN switch is set
to AUTO.
Flashes on and off when passing
waypoint, if AUTO/MAN switch
is set to MAN. Light will extin-
guish if AUTO is selected or if a
course change is inserted.
WARN lamp
Lights red to alert pilot INS self-
test circuits have detected a sys-
tem fault. Illumination may be
Figure 3-23. INS Control Display Unit (C-IV-E)
3-44
