hydraulic systems fail, the rudder servo cylinders
automatically receive hydraulic power from the
backup hydraulic system (flight control backup
module).
The rudder trim switch on the EXT
ENVIRONMENT/THROTTLE control panel enables
trimming of the aircraft in yaw. Setting the switch to
L or R provides a trim-left or trim-right input,
respectively, to the rudder trim actuator. The actuator
provides rudder movement through the rudder-feel
assembly, the yaw summing network, the reversing
network, and the rudder servo cylinders.
ELECTRONIC CONTROL SYSTEMS
All electronic flight control servo cylinders are
controlled by electrical impulses from computers.
The computers compare all data received from the
pilot’s control stick, airspeed indicator, altimeter,
angle of attack, and other sensors. They configure all
flight controls for best flight characteristics and
performance of the aircraft. An example of the
electrical portion that replaces the mechanical
Figure 9-15.—Rudder control system.
9-19
