TM 55-1510-222-MTF
P R O C E D U R E
T R O U B L E S H O O T I N G
R E F E R E N C E
(4) Left-hand and right-hand
displays
-
Read
arc-
seconds related to present
inertial position to the
nearest a tenth of a sec-
ond.
(5) HOLD key - Depress to
return to INS normal op-
eration.
h. Magnetic variation - Check as
follows:
(1) Keys 3 and 9 - Depress si-
multaneously.
(3) Right-hand display - Read
magnetic variation to a
tenth of an arc-minute.
Compare with local val-
ues.
NOTE
While operating in the NAV mode, magnetic
variation is computed when aircraft roll is
less than 9° and the magnetic heading input
is valid (absence of error code 17).
(3) DATA/SELCTOR - Mo-
mentarily set to any posi-
tion except L/L WYPT to
return to normal INS dis-
play mode.
i. Distance and Time to Next
Waypoint - Check as follows:
(1)
Data
selector
-
DIS/
TIME.
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