Hydraulics Flashcards
What are the main components of the Hydraulic systems?
Controls and Indications, Hydraulic Systems 1, 2, and 3, EICAS Messages
What functions do the hydraulic systems provide power for?
- Landing gear and main landing gear doors
- Nose wheel steering
- Brakes
- Flight controls (ailerons, elevators, rudder, ground, and multifunction spoilers)
- Thrust reversers
How is the hydraulic system controlled?
Using the hydraulic control panel on the overhead panel in the cockpit
What do the MFD Hydraulic synoptic pages display?
- Actual values
- Pictorial gauges
- Flow paths
- Pump status
- PTU availability
- Shut off valve status
What does the PTU knob do when set to AUTO?
Operates the PTU automatically during takeoff and landing if engine 2 or engine driven pump 2 fails
What indicates a failed PTU on the synoptic page?
A gray circle and a white windmill beneath an amber cross
What is depicted on the synoptic page for engine driven and electrical pumps?
A circle with an internal windmill, with engine driven pumps and PTU displayed larger than electrical pumps
What pressure is the hydraulic system designed to operate at?
Nominal pressure of 3000 psig
What does a cyan reverse video indicate on the quantity indications?
Low quantity
What does an amber dashed line indicate on the hydraulic synoptic page?
Invalid information or a value out of displayable range
Which systems does Hydraulic System 1 supply?
- Left outboard elevator
- Upper rudder
- Left Engine 1 Thrust Reverser
- Left and Right Multifunction spoilers, Panels 4 and 5
- Left and right Ground spoilers, Panel 2
- Outboard brakes
- Emergency parking brake
Which systems does Hydraulic System 2 supply?
- Left and right hand inboard PCUs
- Left and right hand inboard Ailerons
- Right Engine Thrust Reverser
- Left and right Multifunction spoilers, panels 3 and 6
- Left and right Ground spoilers, panel 1
- Inboard brake
- Nose wheel steering
- Main landing gear (MLG) and doors
- Landing gear retraction and extension
- Emergency parking brake
What does Hydraulic System 3 supply?
- Right hand outboard elevator
- Lower rudder actuator
- Left and right hand outboard ailerons
What is the purpose of the power transfer unit (PTU)?
Transfers hydraulic power from system 1 to system 2 without mixing fluids
What conditions must be met for the PTU to automatically start?
- Flaps not set to zero or landing gear not up and locked
- EDP 1 not failed
- Hydraulic reservoir 2 quantity is above 15%
What happens in the event of an engine flameout regarding the EDP?
FADEC automatically commands the unload of the respective EDP, reducing hydraulic system pressure
What does a high temperature display indicate on EICAS for hydraulic systems?
Amber inverse video and a respective HI TEMP EICAS caution message
What is the role of pressure accumulators in systems 1 and 2?
Maintain a constant pressure during periods of transient flow demands and avoid pump cavitation
What is the primary power source for Hydraulic System 3?
Electric hydraulic pump 3A
Fill in the blank: Hydraulic fluid cannot be transferred from one system to another as there is no _______.
fluid communication point
True or False: The electric hydraulic pumps in systems 1 and 2 operate without pilot action during normal operation.
True
