CBT - HYD Flashcards
How many hydralic sources are ther on the A380?
Two Hydraulically Powered Systems (G+Y)
Backup Electrical Powered system
What is special about the HYD fluid reserviors?
G Reservoir is ENG 1
Y is ENG 4
They are pressurized by engine bleed to prevent pump cavitation
What is the role of the fire shut off valved?
Prevents HYD fluid from flowing into the fire and sustaining it in case of engine fire
What proivides the pressure for the G+Y HYD?
What is the pressue?
Four Engine Driven Pumps (EDPs) (two per engine) pressurize each hydraulic system.
Two EDPs are sufficient to pressurize one hydraulic system.
Pressurized at approx 5000 psi
How can HYD pressure be provided on the ground when engines are not running?
Four electric motor pumps (ELEC PMPS) can provide hydraulic power only on the ground and when the engines are not running.
They operate automatically to open cargo doors with the G and BWS with Y
What computer monitors, controls and relays HYD information?
Each hydraulic system is controlled and monitored by its on-side Hydraulic System Monitoring Unit (HSMU).
One can take over the other’s functions in case the other fails
What logic does the HYD ELEC Pump pb sw follow?
So if during pushback the yellow is manually set to on it will inhibit the auto function for the BWS and degrade its performace
When does the pressure indication turn amber?
below approx 2900 psi
What do these indications mean on the HYD SD page
What HYD fails may be able to be recovered for appraoch?
Low air pressure in the resrvoir and overheat may be be no longeer the case by the time you shoot the approach. i.e. the fauly lights going off foe overheat and no pressure fluctuations occuring if the pumps are turned back to on on a lower altitude for the approach.
Before Walkaround procedures
When checking the Hydraulics, the Green system level can be done from the refill level due Cargo doors.
How much do the doors drain?
How many liters does the refill level represent?
The current hydraulic fluid volume (green band) in the Green hydraulic system reservoir decreases of 1.5 l per open cargo door.
The normal filling range (or movable index) is displayed in green on the right hand side of the reservoir. This movable index represents the normal volume of fluid with a +/- 3 l margin.
