Cessna 172P Pilot's Operating Handbook And Flight Manual page 329

PILOT'S OPERATING HANDBOOK
SUPPLEMEIVT
19
CESSNA
SOOA
AUTOPII,OT
(TYPE AF-39õA)
SUPPLEMENT
CESSNA NAVOMATIC
3OOA
AUTOPILOT
(Type
AF-39541
sEcTtoN
I
GENERAL
The
Cessna 8004 Navomatic
is
an
all electric, single-axis (aileron
control) autopilot system that provides
added
lateral
and directional
stability.
Components &re
&
computer-a¡nplifier, a
turn
coordinator,
a
directional glfro,
&n
aileron actuator
and a course
deviation indicator(s)
incorlrorating
a
localizer reversed (BC) indicator light.
Roll
and
yaw motions
of
the airplane
are
sensed
by
the
turn coordina-
tor gyro. Deviations from
the selectod
heading
aro sensed
bythe direction-
al gyro.
The computer-amplifier eloctroniaally computes tho necessary
correction
and
signals the actuator to move the ailerons to maintain the
airplane in the
commanded
lateral
a,ttitude
or heading.
The
actuator includes
a thermoetatic switch which monitors
the
operating temperature
of the
motor. If
the
temperature
becomes
abnormal,
the thermostatic switch opens and disengages the autopilot to remove
power from
the
actuator. After approximately
10
minutes,
the
switch
wiII
automatically
close
to
reapply power
to the actua,tor and a,utopilot
system.
The
3004 Navomatic
will
also íntercept
and
track
a
VOR
or
localizer
course using signals from
a
VHF navigation receiver.
The
operating controls for the
Cessna 3004
Navomatic
are
located on
the front panel of the computer-amplifier and on tho directional gyro,
shown
in Figure
1.
The
primary function
pushbuttons (HDG SEL, NAV
INT,
and
NAV
TRK), are interlocked
so
that only
one
function
oan
be
selected
at
a time. The
HI
SENS and BACK CIìS pushbuttons are not
interlocked
so
that either
or
both
of these
funotions
can
be
selected
at
any
time.
30
May
1980
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