13. Hydraulics Flashcards
Recall HYDRAULIC SD symbology and color-coding
Pre-Flight Hydraulic Fluid Level
Cyan – Normal (levels depicted are post engine start)
L/R Engine Hyd Pump
White – Commanded off
Green – Commanded on
Amber – Commanded on with low pressure. “P” displayed
Auxiliary Pump
White – Commanded off
Green – Commanded on
Amber – Commanded on with low pressure. “P” displayed
Hydraulic Pressure
White – Pressure within limits
Amber – Pressure exceeds high or low limits (value will be boxed)
Hydraulic Power Transfer Unit (PTU)
White - Commanded OFF
Green - Commanded ON
Hydraulic Fluid Quantity
White – Fluid level within limits
Amber - Fluid level below limits (value will be boxed)
Hyd Fluid TEMP HI
Amber – Fluid temp exceeds high limit (display will be boxed)
Hydraulic Fluid Reservoir
White - Fluid level within limits (Reservoir outlined)
Gray - Fluid level within limits
(Fluid shaded)
Amber - Fluid level below limits
Recall the function of the AUX hydraulic switch
ON - auxiliary pump is commanded on
OFF - auxiliary pump is commanded off
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 electrically driven auxiliary pump, located in the right wheel well, has two purposes: to back up the right hydraulic system in flight 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
Recall the function of the HYD CONT RUDDER switch
When the switch is pushed, OFF illuminates, hydraulic power to the rudder is shut off, and the rudder reverts to manual operation
Allows selection of manual rudder operation
Recall the function of the TRANS pump switch
ON - pump shutoff valve commanded open: transfer pump operative
OFF - pump shutoff valve commanded closed: transfer pump is inoperative
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
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
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 L/R hydraulic systems
Right Hydraulic System
Left and right outboard spoilers
Rudder
Right thrust reverser
Landing gear
Left Hydraulic System
Left and right inboard spoilers
Left engine thrust reverser
Elevator augmentation system
Both Hydraulic Systems
Slats
Flaps
Rudder limiter
Nosewheel steering
Brakes
Anti-skid
