Rudder Electric Trim Tab; Electric Trim Actuator Replacement - Thrush Aircraft S2R–T660 Maintenance Manual

B. Center and lock the rudder.
C. Adjust the turnbuckles in each rudder cable, at fuselage station 208.00, to bring the rudder pedals
approximately 11.00 inches from the back of the hopper.
If the turnbuckles run out of adjustment, relocate adjustment strap
on rudder horn to shorten cable.
D. Safety-wire the turnbuckles with 0.041 stainless steel wire.
E. Adjust and lock the rudder stop bolts, located at the base of the rudder post, to limit the travel of the
rudder to 22 (±1) degrees left and right of center. (Fig. 7-8)
RUDDER ELECTRIC TRIM TAB (Fig. 7-10)
Thrush Aircraft Inc has an electric rudder trim unit that replaces the fixed position trim tab and is rigged to
obtain straight flight; then it can be electrically adjusted to maintain straight flight.
The rudder has a large trim tab which is electrically operated and also serves as a servo. The tab's travel is
to the left to assist in right rudder. Rigging is accomplished by locking the rudder and trim tab in the center
position. Place the electric actuator in the retracted position and bellcrank in the vertical toward the actuator
as much as possible without contact with vertical. Adjust connecting rod to align with bellcrank and install
hardware. Set outside connecting rod to connect to bellcrank and trim tab. Operate trim tab to ensure
proper operation and smooth travel. The tab can be adjusted from this point to suit the operation. Max
deflection 8.6° trailing edge left.

ELECTRIC TRIM ACTUATOR REPLACEMENT

A. Remove service cover on left side of vertical.
B. Disconnect the electrical wires. Mark each wire for identification.
C. Remove bolt connecting to bellcrank.
D. Remove bolt holding motor to vertical and remove actuator.
The new actuator will need to have knife splices
placed on wire.
E. Install new motor in the reverse procedure as outlined for removal.
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THRUSH AIRCRAFT INC - T660 TURBO THRUSH
AIRCRAFT MAINTENANCE MANUAL
*NOTE *
* NOTE *
Effective: 01/10/05