Directional Gyro Indicator - Piper Cherokee Six Service Manual

PIPER CHEROKEE SIX SERVICE MANUAL
9-20. TROUBLESHOOTING.
TABLE IX-II. DIRECTIONAL GYRO INDICATOR
Trouble
Cause Remedy
Excess drift in either
direction.
Setting error.
See Part 9-19.
Defective instrument.
High or low vacuum.
If vacuum is not
correct, check for the
following:
a. Relief valve im-
properly adjusted.
b. Incorrect gauge
reading.
c. Pump failure.
d. Vacuum line kinked
or leaking.
Replace instrument.
a. Adjust.
b. Replace gauge.
c. Repair or replace.
d. Check and repair.
Check for collapsed
inner wall of hose.
Dial spins during turn.
Dial spins continuously.
Limits (55
°
bank) of
gimbal exceeded.
Defective mechanism.
Recage gyro in level
flight.
Replace.
9-21. REMOVAL AND REPLACEMENT. Refer to Paragraph 9-74 of this section.
9-22. GYRO HORIZON.
9-23. GENERAL. The gyro horizon is essentially an air driven gyroscope rotating in a
horizontal plane and is operated by the same principal as the directional gyro. Due to the
gyroscopic inertia, the spin axis continues to point in the vertical direction, providing a
constant visual reference to the attitude of the airplane relative to pitch and roll axis. A bar
across the face of the indicator represents the horizon and aligning the miniature airplane to
the horizon bar simulates the alignment of the airplane to the actual horizon. Any deviation
simulates the deviation of the airplane from the true horizon. The gyro horizon is marked
for different degrees of bank.
INSTRUMENTS
Issued: 8/17/72
2K14