Hydraulics Flashcards
There are 3 separate and independent hydraulic systems. Designated as:
Green, Blue, Yellow
Recall the power sources of each hydraulic system.
Green - Eng pump (primary) and PTU
Blue - Electric pump (primary) and RAT (alternate)
Yellow - Eng pump (primary), PTU, electric pump and hand pump
Explain the displays of the hydraulic system’s reservoir quantity indicator on the ECAM HYD page.
Green pointer
Green rectangle
Amber rectangle
Green pointer - fluid quantity
Green rectangle - range of full quantity
Amber rectangle - ECAM RSVR LO LVL caution message
BLUE ELEC PUMP when its pb is selected AUTO (lights out).
On the ground: pump auto activated and runs continuously with first engine start
Inflight: pump runs continuously regardless of engine operation provided AC power is available
Fire Shutoff valve indications on the ECAM HYD page.
o Green and Yellow system Fire Shut off valves are
depicted below the green engine pump depictions.
o Controlled by the respective ENG 1(2) FIRE pb.
Recall which pumps are depicted on the ECAM HYD page.
o Green Sys ENG 1 PUMP
o Blue Sys ELEC PUMP
o Yellow Sys ENG 2 PUMP
o Yellow Sys ELEC Pump
o PTU (Power Transfer Unit)
o Ram Air Turbine (RAT)
Yellow Electric Pump is selected ON.
▪ ON (white) appears on the YELLOW ELEC PUMP pb.
▪ The triangle on the ECAM HYD page next to the white
ELEC indication turns solid green.
Explain the function of the Power Transfer Unit (PTU).
The PTU is a bidirectional hydraulic motor/pump which provides an alternate power source to either the Green or Yellow hydraulic systems.
NOTE: The PTU transfers power and not fluid between the Green and Yellow systems.
Describe the PTU indications on the ECAM HYD page.
Green arrows
Amber arrows
Solid green arrow pointing left
Solid green arrow pointing right
o Green arrows pointing away from the white PTU label
indicate that the PTU is armed and not operating.
o Amber arrows indicate the PTU pb has be either been
selected OFF or inhibited.
o Solid green arrows pointing to the left indicate that the
PTU is supplying pressure to the Green hydraulic system.
o Solid green arrows pointing to the right indicate that thePTU is supplying pressure to the Yellow hydraulic system.
Recall the indication on the E/WD memo section when the PTU is operating.
HYD PTU
Describe the conditions that will automatically inhibit PTU operation.
o When ENG MASTER switches are in opposite positions (one ON the other OFF), and either:
- Parking brake is on.
or
- Nose wheel steering is disconnected by the towing lever on the nose gear.
o When the Yellow Electric pump is activated through either cargo door’s operation.
FAULT light in the PTU pb.
Low air pressure
Low fluid level
High fluid temp
Note: The FAULT light does not represent the status or condition of the PTU.
RAT MAN ON pb.
o Used to manually deploy the Ram Air Turbine (RAT), which provides alternate power to pressurize the Blue hydraulic system.
o The emergency generator is not energized with use of this pb.
NOTE: The RAT will not automatically deploy with a failure of the Blue Electric pump.
Indications when the RAT is deployed.
RAT OUT on E/WD
White hollow arrow next to RAT indication turns solid green and a line connects to the blue system
