Hydraulic Flashcards
What is the normal pressure of the HYD system ?
3000PSI
2500PSI if powered by RAT
What system can pressurizes the Yellow HYD system ?
ENG 2 pump
Can be ELECT Pump or hand pump
What system can pressurizes the Blue HYD system ?
Elect pump
And RAT in an emergency
Can any fluid be transferred with the PTU ? And when will it automatically start ?
No
Diff pressure of 500PSI
When will the RAT automatically deploy ?
when AC BUS 1 & 2 are lost
What system pressurises the HYD reservoirs
HP bleed from ENG 1, if too low can use the pressure from crossbleed duct
It’s avoid cavitation
What are the main systems powered by the green HYD ?
Landing gear
Flaps/slats
Reverser 1
Normal brakes
flight controls
What are the main systems powered by the Blue HYD ?
Emer gen
Slats
flight controls
What are the main systems powered by the Yellow HYD ?
Flaps
Alternate braking
Parking brake
NWS
Flight controls
Reverser 2
Cargo door
What are the main operational consequences of loosing Green HYD ?
-No landing gear retract => Gravity extension
-Loss of autobrakes and normal brakes
-landing distance due to 2 spoilers lost and 1 rev
What are the main operational consequences of loosing Blue HYD ?
- Loss of emer gen if loss of fluid
- loss of redundancy
- slightly longer landing distance
What are the main operational consequences of loosing Yellow HYD ?
- can’t vacate due to no NWS
- landing distance due to 2 spoilers and Rev 2 lost
- loss of alternate braking => Check pressure on stand for park brake
For a dual HYD failure, how would you describe by few words the main consequences of loss of B+Y, G+B, G+Y ?
B+Y => Least detrimental
G+B => controllability
G+Y => Stopping
What are the main operational consequences of dual HYD failure B+Y ?
- Normal law but no AP
- no NWS
- increased landing distance
- Landing gear gravity extension to protect remaining system
- no Speed brakes
What are the commun consequences of any dual HYD failure ?
- CAT 1 landing capability due to AP1&2 Lost
- Landing gear by gravity so no gear retract
- increase landing distance
What are the main operational consequences of dual HYD failure G+Y ?
- Alternate law so direct law landing
- landing distance massively increased due to loss of 4 spoilers, Rev 1&2, antiskid
- No flaps so use of QRH flaps/slats jammed
- No THS
- no NWS
- For landing Gear gravity extension
For landing => All the way to config 3 THEN gear down to maintain some auto trim as long as possible
In dual HYD failure G+Y, how should you configure the A/C for landing and why ?
Use flaps slat jammed QRH
Configure up to Flaps 3 then gear down.
Allow to maintain some auto trim with the elevator and provide sufficient elevator control for the flare.
What are the main operational consequences of dual HYD failure G+B ?
- Alternate law so direct law landing
- Controllability issue due to loss of ailerons => Roll only with 2 spoilers and only one elevator
- loss of slats => So QRH flaps/slats jammed
- for landing gear gravity extension
- For better controllability => at 200kt gear down => Better elevator response in direct law
Why in flight does the G reservoir level always show slight less than the other 2 ?
After gear retraction some fluid is still in the system and not back in the reservoir
What is the purpose of priority valves ?
Disconnect heavy load user if HYD pressure gets low.
What is the purpose of the accumulator ?
help maintain constant pressure by covering transient demands
When does the HYD system PR becomes amber ?
pressure of less than 1450PSI
On G+B SYS fault why do you extent the LDG gear at 200kt ?
Better pitch control in direct law
On G+Y SYS fault, why do you select Flap 3 before gear down ?
once gear is extended you loose the autotrim via the elevators + it provide sufficient elevator control to flare A/C on landing
What HYD service power the ailerons
G+B
