Cessna SKYMASTER 337 Series User Manual

RIGGING
PROCEDURES
FOR
CESSNA
400
AUTOPILOT
(Type
AF-420A)
USED
ON
1979
337, T337
AND
P337
MODELS
ONLY
GENERAL.
To ensure proper operation of the 400 autopilot sys-
tem, the autopilot's rigging should be checked every
200 hours of airplane operation.
AUTOPILOT RIGGING PROCEDURES.
Aileron
Rigging. For checkout
of aileron rigging,
proceed as follows:
NOTE
Before
proceeding
with
the following
proce-
dures,
be sure
the aileron
control
system
has been
rigged in accordance
with instruc-
tions
provided in the
basic airplane's Service
Manual.
Step 1.
Place control wheels
in neutral position
of
ailerons, and secure control
wheels in neutral
po-
sition by using the control lock (P/N 1500027-10).
Step 2.
Remove access plates
to gain access
to
the
autopilot equipment
installed in the right
wing.
Step 3. Ensure that the actuator assembly (16)
is
securely bolted to
the adapter (15), support
assembly (14A) and bracket (14).
Step
4. Check that the
chain portion of the
chain
and
cable assembly
(5)
is closely
centered on
the
actuator sprocket (18).
CAUTION
If the chain
and cable assembly
(5) is to be
replaced,
it is necessary
to remove the two
chain guard posts (17). When chain guard
posts
are being unscrewed
for removal,
use caution
to
not lose
the locking
washers.
Step 5. Ensure
that cable portion
of the chain
and
cable assembly
(5)
is properly
routed thru
pul-
ley bracket
(19) and
on to pulleys
(23) and
is secured
to
pulley bracket
(19)
as shown
on sheet
4.
Step 6.
Ensure
that the
chain and
cable assem-
bly
(5) and
turnbuckle
(3)
are
secured
to the
bell-
crank
assembly
(1) using
bolt (9),
washer
(8), nut
(6)
and
cotter
pin
(7).
Step 7. Attach cable
tensiometer (24)
to chain
and cable
assembly
(5). Tensiometer
should indi-
cate
20 to 30
lbs. If cable
tension
is above
or be-
low 20 to
30 lbs., make
the following
adjustments
to bring
cable tension
to the
desired
tension.
a. Remove
safety
wire (4) from
turnbuckle
(3).
b. If cable
tension is too high,
loosen turn-
buckle (3).
c.
If cable
tension is
too low,
tighten turn-
buckle (3).
d. Reinstall
safety wire (4) on turnbuckle
(3).
Step 8. Remove
cable tensiometer
(24) from
chain and
cable assembly
(5).
Step 9. Remove
control lock securing
the con-
trol wheels.
Step
10. On
control
unit,
pull
out PULL
TURN
control
and leave in detent.
Center roll TRIM con-
trol.
Set GYRO
switch, on
rear of control
unit,
to
OUT.
Step
11. Turn
aircraft
master
switch, avionics
power switch,
and autopilot
(ON-OFF)
switch
to ON
position and allow
actuator to run
to electrical
neutral.
Step
12. After
actuator
has run
to its electrical
neutral position,
turn
autopilot
(ON-OFF)
switch to
OFF
position.
Step 13. While holding ailerons in position where
actuator stopped, insert screwdriver into slot of the
potentiometer adjustment screw (located adjacent to
actuator
sprocket)
and disengage
feedback
potentio-
meter
in
actuator
by twisting
fully
clockwise
and hold
potentiometer
in this
position.
Figure
6-1. Rigging
Procedures
for
Cessna
400 Autopilot
(Type AF-420A)
Used On
1979 337, T337
and P337
Models Only
(Sheet 1 of 5)
6-2

Cessna SKYMASTER 337 Series Specifications

General

Manufacturer	Cessna
Crew	1
Capacity	5 passengers
Length	9.07 m (29 ft 9 in)
Wingspan	11.63 m (38 ft 2 in)
Height	2.84 m (9 ft 4 in)
Power Output	210 hp (157 kW) each
Maximum Speed	322 km/h (200 mph, 174 kn)
Powerplant	2 × Continental IO-360-C
Service Ceiling	5, 791 m (19, 000 ft)