Rudder Rigging; Rudder Trim Tab; Balance Cable Rigging; Elevators - Thrush Aircraft S2R-R1340 Maintenance Manual

THRUSH AIRCRAFT, INC – MODEL S2R-R1340

RUDDER RIGGING

Ref. Figure 7-6
A. Position the rudder pedals at mid-
adjustment position
adjustment channel.
B. Center and lock the rudder.
C. Adjust the turnbuckles in each
rudder cable, at fuselage station
175.12, to bring the rudder pedals
approximately 11.00 inches from the
back of the hopper.
* NOTE *
If the turnbuckles run out of
adjustment,
adjustment strap on rudder
horn to shorten cable.
D. Safety-wire the turnbuckles using
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.

RUDDER TRIM TAB

A fixed-position trim tab is attached to the
lower edge of the rudder. An out-of-trim
rudder can be trimmed by bending the
metal trim tab. Use forming blocks when
bending tab and do not bend more than
0.50 inch deflection in either direction.

BALANCE CABLE RIGGING

The Thrush incorporates a rudder-aileron
balance cable/spring system.
cables are attached to the rudder pedals
and routed out of the cockpit and to the
spring which is attached to the opposite
aileron bell crank.
accomplished with
located on each cable. The system is
correctly adjusted when the rudder and
ailerons simultaneously align in the
neutral position. Ensure there is no
contact between balance springs.
7-12
AIRCRAFT MAINTENANCE MANUAL
in the
relocate the
The
Adjustments are
the turnbuckles

ELEVATORS

Ref. Figure 7-7 & 7-8
Each elevator is attached to the rear spar
of the horizontal stabilizer at two hinge
points. The control stick is connected to
the elevators through the use of a
belcrank, idler, push tubes and elevator
horn. The right and left elevators are
attached to a common elevator horn and
hinge.

ELEVATOR DOWN SPRING

The elevator system has a down spring
attached to the elevator bell crank via a
cable from the top.
around a pulley to the spring which is
attached back to bell crank support
bracket. The cable and spring are
connected with a turnbuckle for final
adjustments. With the flaps up and the
elevator in neutral, the pulley stand
assembly is clamped to flap torque tube
at 48° from center on fwd side. Rig the
cable to obtain a spring length of 39".
The dual cockpit elevator balance spring
is connected to the lower portion of the
forward elevator bell crank and to the left
lower longeron at
193.43. With flaps up and elevator
neutral, adjust the turnbuckle so that the
dual cockpit spring is 36 inches in length.

ELEVATOR REMOVAL

A. Disconnect aft
elevator horns.
B. Disconnect the trim tab push rods at
elevator trim-tab.
C. Remove hardware attaching both of
the elevators horns together.
D. Remove all hinge bolts from leading
edge of elevator.
E. Remove the elevator from aircraft.

ELEVATOR INSTALLATION

A. Position elevator on aircraft.
B. Attach the elevator to the horizontal
stabilizer hinges.
C. Bolt the two elevator horns together.
The cable goes
fuselage station
push tube from
Effective: 01/01/08