Hydraulics Flashcards
Electric Hydraulic Pump OVERHEAT Lights
Illuminated: Hydraulic fluid used to cool and lubricate the corresponding electric driven pump has overheated or the pump itself has overheated
Hydraulic Pump LOW PRESSURE Lights
Illuminated: output pressure of associated pump is low
ELECTRIC HYDRAULIC PUMPS switches
ON - provides power to associated electric motor-driven pump
OFF - electrical power removed from pump
ENGINE HYDRAULIC PUMP switches
ON - deenergizes blocking valve in pump to allow pump pressure to enter system
NOTE: should remain ON at shutdown to prolong solenoid life
OFF - energizes blocking valve to block pump output
Normal and Max pressure for the hydraulic system pressure
Normal: 3000psi
Max: 3500 psi
When will you get a REFILL indication for hydraulics?
When will it show?
What HYD LOW QUANTITY is always armed?
STBY HYD LOW PRESSURE
76%
o Only shows when airplane on ground and both engines shutdown or after landing with flaps up during taxi-in
o STANDBY HYD LOW QUANTITY: always armed
o STANDBY HYD LOW PRESSURE: Armed only when standby pump is operation has been selected or automatic standby function is activated
FLIGHT CONTROL switches
STBY RUD: activates standby pump and opens standby rudder shutoff valve to pressurize standby rudder power control unit
OFF: closes flight control shutoff valve isolating ailerons, elevators, and rudder from associated hydraulic system pressure
ON: (guarded postion) normal operating postion
Flight Control (LOW PRESSURE) lights
Illuminated:
Indicates low hydraulic system (A OR B) pressure to ailerons, elevator and rudder
deactivated when associated FLIGHT CONTROL switch is positioned to STBY RUD and standby rudder shutoff valve opens
STANDBY HYDRAULIC LOW QUANTITY light
Illuminated: Indicates low quantity in standby hydraulic reservoir
always armed
STANDBY HYDRAULIC LOW PRESSURE LIGHT Light
Illuminated:
- indicates output pressure of standby pump is low
- armed only when standby pump operation has been selected or automatic standby function is activated
ALTERNATE FLAPS master switch
OFF - normal operating position
ARM - closes trailing edge flap bypass valve, activates standby pump, and arms ALTERNATE FLAPS position switch
STBY RUD ON light
illuminated:
- indicates the standby hydraulic system is commanded on to pressurize the standby rudder power control unit
How many hydraulic systems?
A / B / standby
What does the hydraulic systems power?
Flight controls Leading edge flaps and slats Trailing edge flaps Landing gear Wheel brakes Nose wheel steering Thrust reversers Autopilots
Can only A or B power all flight controls?
yes, with no decrease in controllability.