TM 55-1510-219-MTF
PROCEDURE TROUBLESHOOTING REFERENCE
F.
AVIONICS FLIGHT CHECKS (CONT)
(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.
(9)
If the terrain band shifts to the right around the second
range marks, increase tilt angle using TILT control until
pattern is displayed throughout the third range marks. Note
new position of TILT control. It should not be more than two
degrees above that noted in step (5).
(10) If the terrain band shifts (in step 8) to the left around the
second range marks, decrease tilt angle using TILT control
until pattern is displayed
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