Hydraulics & Landing Gear Flashcards
What is normal system operating pressure?
3000 psi
2500 psi when powered by the RAT
What pressurises the green system?
A pump driven by engine 1
What pressurises the yellow system?
- pump driven by engine 2
- can also be pressurised by an electric pump which allows yellow hydraulics to be used on the ground with no engine
- hand pump for the cargo doors when no electrical power is available
What pressurises the blue system
- electric pump
- pump driven by the RAT in an emergency
How does the PTU work?
- enables the yellow system to pressurise the green and vice versa
- works when differential pressure is greater than 500 psi
- therefore allows green system to be pressurised on the ground
How is the fire shut off valves closed?
Crew will press the ENG 1(2) FIRE pb
How are the reservoirs pressurised?
- HP bleed air from engine 1 automatically
- If bleed air pressure is too low it will be taken from the crossfeed duct
- systems maintain a high enough pressure to prevent their pumps from cavitating
When will a FAULT light come on the ENG 1(2) pump pb?
- reservoir level too low
- reservoir overheats
- reservoir air pressure is low
- pump pressure is low (inhibited on the ground)
When does the blue elec pump work in AUTO?
Operates after first engine start
When will you get a FAULT light on the PTU pb?
- green or yellow reservoir overheats
- green or yellow reservoir has low pressure
- green or yellow reservoir has low fluid level
What does the BLUE PUMP OVRD pb do on the maintenance panel?
You can put the blue elec pump on and use blue system on the ground
How is the landing gear controlled?
electrically controlled, hydraulically operated
What controls the landing gear extension and retraction?
2 Landing Gear Control and Interface Units (LGCIUs)
Can be extended by a hand crank on the centre pedestal if hydraulics or electrics are lost
Which hydraulic systems is connected to the landing gear?
Green
What is the speed limit for landing gear operation?
260 kt
What supplies the landing gear indicator panel?
LGCIU 1
What supplies the ECAM wheel page?
LGCIU 1 - left triangle
LGCIU 2 - right triangle
What happens when you operate the landing gear handcrank?
- handle turned clockwise for three turns
- system is isolated from the green hydraulics - cut off valve shuts off pressure
- unlocks landing gear doors and main and nose gear
- allows gravity to drop gear
- gear doors remain open
What happens if one LGCIU fails?
The other one takes over
In normal ops they swap after each cycle
What does the red arrow mean on the landing gear lever?
If the landing gear is not locked down when the aircraft is in landing config, red warning appears on ECAM
What system supplies the nose wheel steering?
Yellow
What is the BSCU?
Brake and Steering Control Unit - two onboard
Controls normal braking and anti-skid
A changeover between the channels occurs at each DOWN landing gear lever selection or in case one channel fails
When does the steering system receive hydraulic pressure?
- A/SKID and N/W STRG are on
- towing control lever is in a normal position
- at least one engine running
- aircraft is on the ground
How far can the handle turn the nosewheel?
75 degrees in either direction
