TM 55-1520-240-23-6
7-290
POWER STEERING
7-290
DESCRIPTION
A power steering system is fitted to the aft right landing
gear. The system uses electrical control and hydraulic
power to steer the helicopter during ground maneuvers.
When power steering is not being used, swivel locks can
be engaged to hold the aft wheels in a trailing position.
The locks are operated by the same electrical and
hydraulic system as the power steering.
NO BREAK - WORK HARDER
The system consists of a control module, a control
switch, a swivel lock switch, a control box, and actuators
for the power steering and the swivel locks.
NO BREAK - WORK HARDER
The module is located on the right side of the cabin
at sta. 485. It contains an accumulator, two solenoid
valves, and a check valve. The accumulator reduces
surges and ensures a constant pressure when high
demands are placed on the system. The valves control
fluid flow to the swivel lock actuators and the power
steering actuator. The check valve prevents backflow
between the two solenoid valves.
NO BREAK - WORK HARDER
A swivel lock actuator is on each aft landing gear. The
actuators direct hydraulic pressure to lock and unlock
the swivel locks. A power steering actuator is mounted
on top of the aft right gear. All three actuators are
engaged and disengaged by a switch on the power
steering control box in the cockpit center console.
NO BREAK - WORK HARDER
The entire system can be isolated from the rest of the
utility hydraulic system by a solenoid valve in the utility
pressure control module. The normally open valve is
closed by a switch on the overhead hydraulic control
panel in the cockpit.
7-1077
