Wipaire Wipline 2100, Руководство по обслуживанию и инструкции

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SERVICE MANUAL & ICA
WIPLINE 2100 & 2350 FLOATS
Page 32 Revision N P/N 1002549
Retraction and extension of the main and nose landing gear is affected by a hydraulic actuation system shown
schematically in Figures 5-1, 5-1B, 5-1C, or 5-1D.
The gear system is hydraulically actuated and driven by one reversible electric pump.
A pressure of between 500 psi and 700 psi in the down and up position is maintained in the supply line. When
the pressure falls below 500 psi in the down position and 500 psi in the up position, the pressure switch activates
the pump solenoid, providing power to the pump. When the pressure reaches 700 psi in the down position and
700 psi in the up position, the pressure switch deactivates the solenoid and the pump motor stops. Figure 5-2
shows the electrical schematic of the system. A check valve on the output side of the pump retains pressure in
the system while the pump is off. The pump has an interval relief valve that directs oil back to the pump reservoir
when the line pressure exceeds 800 +100/-0 psi. The system also has an internal relief valve to protect against
thermal expansion when line pressure exceeds 1100 +100/-0 psi.
See Section 8 for disassembly, service and troubleshooting.
The system requires hydraulic oil (Mil-H-5606 Red). To check the fluid level, fill the reservoir with hydraulic oil and
cycle the gear. If the reservoir empties (i.e., fluid disappears in sight glass), stop the cycle by pulling the circuit
breaker on the control panel. Fill the reservoir again and complete the cycle. Continue this procedure until the
fluid level in the reservoir stabilizes (it will vary in level between up and down positions). If the fluid level continues
to decline during gear cycles, check for external leaks. If pump cycles on and off during gear cycle, it may be
necessary to select hand pump to “UP.” Cycle gear “UP” with electric pump, then select gear “DOWN” on hand
pump and cycle gear “DOWN” with electric pump. Repeat if necessary. This manually bleeds system.
NOTE: Fluid level in reservoir in “UP” position is full; “DOWN” position reservoir is half full. Don’t over
fill in “DOWN” position.
A cockpit-mounted switch accomplishes the selection of gear up or gear down. Each landing gear has an
individual indicator light on the selector head allowing the pilot to confirm that each gear has fully retracted or
extended.
At the top of each float deck just forward of the step, a visual indicator is provided for the main gear. Nose gear up
may be determined visually for position.
An emergency hand pump and selector valve is provided in case of total electric pump failure or loss of fluid. The
reservoir has additional hydraulic fluid available only to the hand pump.
The main gear has an over-center lock in both up and down positions. Retraction takes place when pressure
is exerted on the actuator piston driving the actuating arm along the slide track (refer to Figure 6-1). A reverse
process affects extension. Gear position light proximity switches are closed when the cylinder piston (containing
the magnetic material) is adjacent to the switch.
The nose gear has an over-center down lock. Retraction occurs when pressure is applied to the forward face
of the actuator piston and the carriage is drawn along the tracks in the nose box as shown in Figure 8-1. Gear
position light proximity switches are closed when the piston containing the magnetic material has reached either
end of its travel.
6.1 DESCRIPTION AND OPERATION