Hydraulics Flashcards
Recall the function of the AUX hydraulic switch (ON, OFF)
ON – auxiliary pump is commanded on
OFF – auxiliary pump is commanded of
The electrically driven auxiliary pump, located in the right wheel well has two
purposes: to back up the right engine-driven pump and to pressurize the hydraulic systems on the ground when the engines are not running. The auxiliary pump has built-in thermal protection and automatically shuts down if it overheats.
If the right engine driven pump fails, or the right engine fails, the AUX pump may
be used to operate all right system components, including the landing gear.
The auxiliary pump has built-in thermal protection and automatically shuts down if
it overheats
Recall the function of the HYD CONT RUDDER switch
Allows selection of manual rudder operation. When the switch is pushed, OFF illuminates, hydraulic power to the rudder is shut off, and the rudder reverts to manual operation.
Recall the function of the TRANS pump switch (ON, OFF)
The transfer pump, located in the left wheel well, enables a pressurized system to mechanically power an unpressurized system when both system reservoir quantities are normal.
ON – opens valve on each side of Power Transfer Unit (PTU) to connect left and right systems
OFF - closes valve on each side of PTU to disconnect left and right systems
Recall associated precautions with Hydraulic System Test
WARNING: Do not establish hydraulic power which will result in flap, slat, or spoiler movement unless the wing/flap area has been cleared of personnel and equipment. Use an outside observer.
If possible, pressurize the hydraulic system for the first flight of the day exterior inspection. Coordinate with ground crew or another flight deck crewmember to obtain clearance to turn on the TRANS and AUX HYDRAULIC pumps. If no outside observer is
available, the TRANS and AUX pumps may be turned on using an alternate procedure.
Recall the effect of electrical failure on the Engine Driven Hydraulic Pumps
When electrical power is removed from an engine-driven pump, the pump defaults to ON
Recall what items are controlled by the left hydraulic system (3)
Left Hydraulic System • Left and right inboard spoilers • Left engine thrust reverser • Elevator augmentation system
Recall what items are controlled by the right hydraulic system (4)
Right Hydraulic System • Left and right outboard spoilers • Rudder • Right thrust reverser • Landing gear
Recall what items are controlled by both hydraulic systems (5)
Both Hydraulic Systems • Slats • Flaps • Rudder stop limiter • Nosewheel steering • Brakes
Recall the effect on a hydraulic system when pulling an engine fire handle
The associated engine hydraulic shutoff valve is closed and fluid supply to the engine is stopped.
