through 7-4.) Study figure 7-4 as you read about the
send a negative (port) or positive (starboard) electrical
components and their functions.
signal through the control system electronic package
(CSEP) and to the rudder actuator, thereby causing the
There are two rudders mounted vertically across the
rudder to move left or right as directed. The pedal
trailing edge of each propeller duct. The rudders are used
controls are spring-loaded to allow them to return to the
with the bow thrusters to provide turning capability. The
neutral position after the rudder has moved to the
function of the rudders is to deflect propeller slipstream
commanded position.
which, in turn, provides a turning force at the stern of
the craft.
CSEP AND RUDDER INTERFACE AS-
SEMBLY.-- The function of the CSEP is to control and
Operation of the rudder control system is based on
send the command signals initiated by the operator in
hydraulic pressure. In fact, a hydraulic pressure system
the control station to the various components in the craft
supplies power to both the rudder control system and the
control system. The LCAC has two identical CSEPs,
propeller pitch control system. There is a separate
labeled CSEP A and CSEP B. Each CSEP has a single
hydraulic system for each side of the craft, consisting of
circuit specifically for rudder control. A rudder control
pumps, valves, actuators, and piping. The control station
signal initiated by the control station operator will be
operator controls the rudders by moving the rudder
routed through one of these channels to the rudder
control pedals forward or aft, as required. Movement of
control components. The operator can use either CSEP
a rudder control pedal is converted into an electrical
A or CSEP B to route a rudder control signal.
signal. The electric signal, in turn, controls a hydraulic
position actuator that moves the rudder for that side of
RUDDER POSITION DRIVE AS-
the craft to the selected position. Figure 7-3 shows the
S E M B L Y . -- The rudder position drive assembly
location of the rudder control pedals at the steering
contains a valve coil, hydraulic drive servo motor, and
control station. Figure 7-5 shows a side view of the
feedback potentiometer. The CSEP sends an electrical
rudder pedal assembly.
drive signal to the electric drive servo motor through the
valve coil to position the rudders. As the rudders are
P E D A L C O N T R O L S . The control station
positioned, a feedback signal goes to the CSEP. When
operator moves the rudders by operating the two pedals
the feedback signal is equal and opposite to the drive
on the rudder control assembly. (See shaded areas of
signal, the rudders are in the desired position.
figs. 7-3 and 7-5.) The rudder pedals pivot on an axle
to allow the operator to move the rudders in both
RUDDER BLADES. The craft's two rudders are
directions. To move the rudders to full port or full
mounted vertically across the trailing edge of each
starboard, the operator pushes the port or starboard
propeller shroud. The rudder blades are broad, flat,
pedal forward. This action causes a potentiometer to
aerodynamic, movable devices that measure 10.4 feet
Figure 7-5.--Rudder pedals.
7-4
