Elevator Trim Controls; Removal Of Elevator Trim Assembly (Control Pedestal); Installation Of Elevator Trim Assembly - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
g. Check control operation and direction of travel, bolts and turnbuckles for safety and installation of
cable guards.
h. Check the complete elevator control system (including autopilot, if installed) to determine the fric-
tion in the system. Refer to paragraph 5-29. i. Install access plates and panels, tail cone and seats.
5-29. ELEVATOR CONTROL SYSTEM FRICTION MEASUREMENT. (Refer to Section IV.)
5-30. ELEVATOR TRIM CONTROLS.
5-31. REMOVAL OF ELEVATOR TRIM ASSEMBLY (Control Pedestal). (Refer to Figure 5-6.)
a. Remove the access plates attached to the sides of the control pedestal.
b. Remove the aileron trim control knob by removing the roll pin that secures the knob to the screw
assembly shaft and remove knob. Remove the covers from the face of the control pedestal.
c. Remove the right pilot's seat and the right row of passenger seats.
d. Remove the floor panel located aft of the control pedestal, the right panel forward of the main
spar, the right first and second panels aft of the main spar and the panel lateral to the entrance door.
e. Remove the interior access panel to the aft section of the fuselage.
f. To prevent the cables from unwrapping from their drums, block the forward trim cables (6) at the
trim screw assembly within the control pedestal and the aft cables ( 13) at bulkhead 317.75. by one of the
methods shown in Figure 5-10. If the aft screw assembly (19) is also to be removed, remove the access plate
attached to the underside of the horizontal stabilizer, and block the cables at the screw assembly instead of in
the fuselage.)
g. Mark one set of cable ends at station 291.00 to facilitate installation and disconnect the cables at
the tumbuckles (12).
h. Remove the cable guard pins at fuselage station 78.00, 99.00 and 244.00.
i.
Remove one screw from each set of rub blocks at stations 162.50,174.00 and 215.00 and open
them far enough to allow the cable ends to pass through.
j.
Remove the screw that secures the elevator trim control wheel on the spline shaft and remove
wheel.
k. Remove the screws that attach the screw assembly to the control pedestal.
5-32 INSTALLATLON OF ELEVATOR TRIM ASSEMBLY (Control Pedestal). (Refer to Figure 5-6.)
a. Ascertain that the cable is evenly wrapped on the trim drum (centered) and blocked to prevent
unwrapping. (Refer to Wrapping the Trim Drum. paragraph 5-57.)
b. Position the trim screw assembly in the control pedestal and secure.
c. Draw the cables from the pedestal through the fuselage to the aft section of the fuselage.
d. If the trim cables (13) from the elevator are installed, connect the cable ends. (If the cables from
the elevator are not installed, pull the cables tight and block them in the fuselage at bulkhead 244.00.)
e. With the cables installed and connected, install the cable guard pins at stations 78.00, 99.00 and
244.00, and close and secure the rub blocks at stations 162.50, 174.00 and 215.00.
f. Remove the cable blocks.
g. Install the trim control wheel on the trim screw shaft at the side of the pedestal and secure with
screw.
h. Set cable tension with the turnbuckles ( 12) at station 291.00 per Table V-ll and check rigging and
adjustment per paragraphs 5--7 and 5--8.
i.
Install the cover on the face of the control pedestal and the aileron control knob and secure knob
with roll pin.
j.
Install access plates, panels, and seats.
Revised: 3/31/94
SURFACE CONTROLS
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