TM 55-1510-221-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
(4)
STAB OFF switch Push ON.
(5)
While flying level (0° pitch, 0° roll),
adjust TILT control to obtain a video
pattern throughout the upper range
marks Note TILT control setting If the
inner ring of video is not parallel to the
range mark, the error is caused by
mechanical
displacement
of
the
antenna about the roll axis of the
aircraft. Use TILT control to determine
exact error Correct on ground, If
necessary,
before
further
inflight
calibration.
(6)
Push off the STAB OFF button to
restore stabilization.
(7) Pattern observed in step (5) should not
change If the pattern shifts either left or
right around the second range marks,
ground check leveling of the gyro and
accuracy of the horizon indicator. Use
TILT control to find exact error
(8) Roll the aircraft 20° right For perfect
stabilization, the terrain band should be
displayed throughout the third range
marks.
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