Rigging And Adjustment Of Stabilator Trim - Piper Dakota Maintenance Manual

INSTALLATION OF STABILATOR TRIM ASSEMBLY (AFT) (figure 27-l8)
1. Wrap trim barrel as follows:
a. Lay center (as measured equally from each end to center of cable) of trim cable in slot of barrel.
b. Bring upper cable through diagonal slot in flange at upper end of barrel and wrap down in a
counterclockwise direction.
c. Bring lower cable through diagonal slot in lower end of barrel and wrap up in a clockwise
direction.
d. Wrap cable as evenly as possible to obtain 23 wraps on barrel as viewed from side opposite slot
and with cables extending out from slotted side.
2. Block both cables by clamping them between two pieces of wood laid next to wraps to preven them
from unwrapping.
3. Ensure that barrel bushings are installed in rib plate and clip.
4. Lubricate bushings and install trim barrel in bushings between two support ribs. Attach bottom
diagonal rib to horizontal rib and secure with bolt, washers, and nuts.
5. Install thrust washer, washer, and snap ring on lower end of barrel.
6. Install trim screw in barrel and secure each end with a cotter pin through screw.
7. Route cables into fuselage and attach ends to forward trim cables.
8. Remove blocks holding forward cables tight and aft cables at barrel.
9. Set cable tension and check rigging and adjustment per Rigging and Adjustment of stabilator Trim.
10. Check safety of all turnbuckles.
11. Install tall cone and secure with screws.
12. Install access panel to aft section of fuselage.
RIGGING AND ADJUSTMENT OF STABILATOR TRIM (figure 27-l8)
1. Level airplane. (Refer to Leveling, chapter 8.)
2. Check for proper stabilator trim cable tension as given in figure 27-l5. If cables were disconnected,
rotate control wheel several times to allow cables to seat and recheck tension.
3. Secure stabilator in neutral position. To find neutral, place a rigging tool on upper surface of stabilator
as shown in figure 27-l6. Zero a bubble protractor, set it on rigging tool and tilt stabilator until bubble
is centered.
4. With stabilator centered, turn trim wheel until aft end of turnbuckle of right trim cable is
approximately two inches forward of double pulleys at top of rear bulkhead at station 228.3.
5. Check that trim screw is turned down until cotter pin stop in top of screw is contacting plate on
horizontal support rib of trim assembly. If stop is not contacting plate, links between screw and trim
control arm are not disconnected. Disconnect by removing connecting nut, washer, and bolt. Wi t h
turnbuckle still two inches from pulley, turn screw down until pin contacts plate.
6. Check rod end on tab actuating arm for approximately six threads forward of jam nut.
7. Connect links to trim screw and secure with bolt, washers, and nut.
8. Turn trim control wheel until trim tab streamlines with neutral stabilator.
9. Check bubble of protractor over neutral tab and then check tab travels as given in figure 27-l5. Degree
of travel on protractor is determined by taking difference between protractor reading at neutral and up,
and neutral and down. Bubble must be centered at each reading with airplane level.
10. To obtain correct travels, if incorrect, adjust by disconnecting links at actuating arm rod end and
turning end in or out as required. Reconnect links to rod end.
11. Secure jam nut on actuating arm rod end.
PIPER AIRCRAFT
PA-28-236
MAINTENANCE MANUAL
1L11
27- 35 - 00
Page 27 - 36
Reissued: August 1, 1986