TM 55-1510-215-10
1.
Clock
5. Autopilot/yaw damp/trim switch
2.
Control wheel steering switch
6. Engine controls lock bar
3.
Electric trim switches
7. Rudder lock pin
4.
Microphone switch
AP011649
Figure 2-16. Control Wheels and Control Locks
neutral position by the largest of the two pins, which is
control pedestal. The dual element thumb switch is
installed horizontally through the pilot's rudder pedals.
moved forward for trimming nose down, and aft for nose
Removal sequence is a reverse of the installation
up. When released, the switch returns to the center (off)
procedure.
position. Any activation of the trim system through the
copilot's trim switch will be over ridden by activation of
2-43. Trim Tabs.
the pilot's switch. A preflight check of the dual element
switches should be accomplished before flight by moving
Trim tabs are provided for all flight control surfaces.
the switches individually on both control wheels. No one
These tabs are manually actuated, and are mechanically
switch alone should operate the system; operation of
controlled by a cable-drum and jack-screw actuator
elevator trim should occur only by movement of pairs of
system. Elevator and aileron trim tabs incorporate anti-
switches. The trim system disconnect is a bi-level, push
servo action, i.e., as the elevators or ailerons are
button, momentary type switch, located on each control
displaced from the neutral position, the trim tab moves in
wheel. Depressing the switch to the first of two levels
the same direction as the applied control surface, thus
disconnects the autopilot and yaw damp system, and the
increasing the effective control surface area and the
second level disconnects the electric trim system. The
manual force required to apply it. This action increases
manual trim control wheel and the electric trim system
control pressure. The rudder trim tab is adjustable left or
cannot be used simultaneously.
right as required and maintains an "as adjusted" position
throughout the full range of rudder deflection.
c. Aileron Trim Tab Control. The aileron trim tab
control, placarded AILERON TAB - LEFT, RIGHT, is on
a. Elevator Trim Tab Control. The elevator trim tab
the control pedestal and will adjust the left aileron trim
control wheel placarded ELEVATOR TAB - DOWN, UP,
tab only (fig. 2-6). The amount of aileron tab deflection,
is on the left side of the control pedestal and controls a
from a neutral setting, as indicated by a position arrow,
trim tab on each elevator (fig. 2-6). The amount of
is relative only and is not in degrees. Full travel of the
elevator tab deflection, in degrees from a neutral setting,
tab control moves the trim tab 7-1/2 degrees up and
is indicated by a position arrow.
down.
b. Electric Elevator Trim. The electric elevator trim
d. Rudder Trim Tab Control. The rudder trim tab
system is controlled by dual element thumb switches on
control knob, placarded RUDDER TAB - LEFT,
the control wheels, a trim disconnect switch on each
RIGHT on the control pedestal, controls adjustment
control wheel, and a circuit breaker located on the
of the rudder trim tab (fig. 2-6). The amount of rudder
2-34 Change 10
