Piper Cherokee Six - Directional Gyro Indicator

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