TM 55-1510-220-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
F.
AVIONICS FLIGHT CHECKS (CONT)
f.
Latitude and longitude position - Check as follows:
(1) Data selector - L/L POS.
(2) Displays - Read present position latitude in the left-hand display and present position longitude
in the right-hand display. Both display indications are to a tenth of a minute.
(3) HOLD key - Depress. Key will illuminate. Latitude and longitude displays will freeze at the
values which were present when the HOLD key was depressed.
NOTE
While the HOLD key is illuminated, TACAN and data link
updates are prohibited.
g
Latitude and longitude inertial position - Check as follows: Data selector - L/L WYPT (HOLD key
should still be illuminated).
(1) Left-hand and right-hand displays - Read latitude and longitude of present position to a tenth of
a degree. Compare with values noted in latitude and longitude position check above.
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