TM 55-1510-221-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
G. AVIONICS FLIGHT CHECKS (CONT)
(8)
Data selector - Set to DIS/TIME
(9)
Keys 7 and 9 - Depress
simultaneously Compare
distance to TACAN station
shown in the left-hand
display with the distance
shown on the INS
TACAN range display
(10) Mission control panel - Check that
INS UPDATE
annunciator light is illuminated.
(11) Data selector - Return INS to normal
by setting to
any
position except WYPT or DIS/TIME.
c.
Ground track angle and ground
speed - Check as
follows
(1)
Data selector - TK/GS.
(2)
Left-hand display - Read correct
ground track angle to the nearest
tenth of a degree. Compare with
course deviation indicator.
(3)
Right-hand display - Read correct
ground speed to the nearest knot.
Compare with airspeed indicator.
d.
Heading and drift angle - Check as
follows
4-12
