TM 55-1510-219-MTF
PROCEDURE TROUBLESHOOTING REFERENCE
NOTE
The pitch and roll output levels from the vertical gyro
are governed by the 115 volt, 400 Hz excitation and
the linearity of the gyro, plus the ability of the gyro to
follow the motion of the aircraft. The accuracy
contributed by the antenna is its ability to respond to
the gyro outputs. As a result of these factors, the
stabilization system accuracy can vary up to 10%
of the pitch or roll angle of the aircraft.
(1)
Fly to an altitude above 10,000 feet.
(2)
MODE switches - WX.
(3)
RANGE switches - 120 or 60.
(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.
4-37
