Flashcards in Hydraulics - Complete Deck (45):
The Thrust Reverser is powered by what?
The left engine thrust reverser is powered by... ?
Hydraulic System 1
The EICAS message HYD 1 HIGH TEMP indicates what?
Hydraulic Fluid temp has reached 100 degrees
What happens when hydraulic fluid temp reaches 125 degrees?
The hydraulic SOV closes, isolating the EDP from the flow line.
What does the hydraulic system 1 supply?
Elevator - Left side outboard actuators
Rudder - Upper actuator
Thrust Reverser - Left engine
Multi Function Spoilers - Left and Right panels 3 and 4
Ground Spoilers - Left and Right panel 2
Emergency Parking Brake
The Emergency Parking Brake is powered by... ?
Hydraulic System 1
Turning the PTU switch to ON accomplishes what?
It operates the PTU continuously, bypassing system logic.
What does the EICAS message HYD 1 OVERHEAT mean
Hydraulic fluid temp has reached 145 degrees
What can be done if you have an HYD 1 OVERHEAT warning message
manually shut the SOV via the ENG PUMP SHUTOFF guarded switch.
How is the hydraulic system effected in the event of an engine flameout?
The FADEC depressurizes the hydraulic system to reduce torque loads to facilitate a windmill start.
The engine 1 ACMP hydraulic pump is powered by?
AC Bus 2
When is ACMP 1 activated with the pump switch in the auto position?
EDP or Engine failure
Flaps selected to any position out of 0
What do the ACMPs do during landing?
They operate for 60 seconds to avoid abrupt pressure bumps incase of engine failure
With the selector to AUTO, the ACMPs are activated on the ground when??
Flaps are selected to any position greater than 0
thrust levers set to Takeoff or
Ground Speed greater than 50 KTS
What hydraulic system powers the nose wheel steering?
When the Thrust Levers are advanced to TOGA, what happens to the ACMPs
the ACMPs will be activated for 60 seconds to avoid pressure variations in the event of engine failure.
ACMP 2 turns off automatically when?
After 6 minutes have elapsed after setting the parking brake.
The inboard brakes are are activated by which hydraulic system
Hydraulic System 2
ACMP 2 is powered by which bus
AC BUS 1
ACMP 2 is automatically powered on the ground when?
Engine 1 is running and parking brake released
During Engine 1 start if parking brake has been applied within the last 6 minutes.
What is the purpose of the PTU
To assist the landing gear retraction or extension, should a right engine failure or right hydraulic EDP failure occur
What does hydraulic system 2 supply?
Elevator - left and right inboard
Ailerons - right and left inboard actuator
Thrust Reverser - Engine 2
Multi Function Spoilers - left and right panels 5
Ground Spoilers - Left and Right panel 1
Nose Wheel Steering
Landing Gear - Extension and Retraction
Emergency Parking Brake
On the hydraulics page, what happens in the event of any failure?
The size of the letters inside the associated distribution box increase to attract attention.
On the hydraulic synoptic page what does a amber dashed circle with no line represent
On the hydraulic synoptic page what does a white circle with a diagonal line represent
On the hydraulic synoptic page what does a white circle beneath an amber cross
On the hydraulic synoptic page what does a flow line with a white / amber dashed line represent
pressure is undetermined
How does the PTU function
It is a hydraulic pump in system 2 driven by a hydraulic motor in system 1
Should a right engine failure or hydraulic EDP failure occur, how is the landing gear pressurized?
By the PTU on Hydraulic System 2
The PTU will automatically be started when...
When ALL of the following:
Flaps not set to 0
EDP 1 not failed
Hydraulic reservoir 2 quantity above 12%
In the event of hydraulic overheat conditions are the associated pumps turned off?
Yes... except for System 3. But only in an electrical emergency
During an electrical emergency the overheat protection is inhibited to prevent Hydraulic system 3 from being shut off.
the PTU will automatically be activated if in the AUTO position when... ?
If Engine 2 or EDP 2 fails during takeoff and landing.
Hydraulic System 3 provides pressure to what systems?
Elevator - right hand outboard actuators
Rudder - lower actuator
Ailerons - left and right outboard actuators
During an electrical emergency, what indications will there be for hydraulic system 3 overheat?
No EICAS messages as they are inhibited to prevent from the crew from shutting down hydraulic system 3
When does hydraulic pump 3B turn on?
When ACMP 3A fails
How does the Hydraulic system 3 accumulator differ from the other accumulators?
It is the same except during electrical emergencies.
The Hydraulic 3 accumulator will provide hydraulic pressure to its respective flight controls from the beginning of RAT deployment till the time the ACMP 3A is powered by the Essential Bus
What does the pump unloader valve and what system is it on?
System 3 incorporates 2 dedicated valves which are used in the event of electrical emergency. The pump unloader valve reduces the discharge pressure during ACMP 3A start up, reducing torque and therefore electrical demand on the RAT
What does the pump flow limiter valve do?
In the event of an electrical emergency, the pump limiter valve (one of 2 dedicated valves in system 3) is used to reduce the amount of flow provided by the ACMP 3A, thus limiting the electrical demand on the RAT.
EICAS message HYD 3 VLV FAIL indicates what?
That one or both of the dedicated valves in system 3 used during electrical emergencies have failed.
What type of hydraulic fluid is used and what is the pressure?
Skydrol at 3000 psi
What happens when hydraulic fluid temperature reaches 125 degrees C
The hydraulic SOV closes
Which hydraulic 3 pump is the primary vs. backup
3A is primary, 3B is backup
How does Hydraulic 3 avoid overloading the RAT in the event of an electrical emergency
2 dedicated valves
Flow Limiter Valve - reduces flow to limit electrical draw
Pump Unloader Valve - reduces torque to start the pump
Where are the Hydraulic Systems located?
Systems 1 and 2 are under and behind the wing
System 3 is in the rear fuselage behind the pressure bulkhead