E-Jet Hydraulics

Question 1

How many Hydraulic systems does the E-jet have?

Answer 1

3 independent hydraulic systems

Question 2

What do the Guarded SYS1 and SYS2 Engine Pump shutoff valve buttons do?

Answer 2

Closes the hydraulic SOV, isolating respective engine driven pump from the associated hydraulic system

Question 3

Which Hydraulic system operates the landing gear?

Answer 3

Sys 2

Question 4

Which system operates the nose wheel steering?

Answer 4

Sys 2

Question 5

At what temperature does the SOV for the Hyd Pumps shut off automatically?

Answer 5

125 degrees

Question 6

What is the function of the Electric Hydraulic 1 pump?

Answer 6

Functions as a back-up for the EDP1

Question 7

When does the Electric Hydraulic Pump 1 activate?

Answer 7

EDP or Engine fail, or when flaps are selected to greater than 0 in the air.

On the ground:
Flaps selected to greater than 0, and:
Thrust levers set to TOGA, or
Ground speed greater than 50kts

Question 8

What is the difference in Hyd 2 System reservoirs between the 170/175 and 190/195?

Answer 8

The reservoir in the 190/195 has a greater capacity

Question 9

When does the Electric Hydraulic Pump 2 activate on the ground?

Answer 9

Eng1 running and parking brake released

During Eng 1 start (once N2 reaches 40%) if parking brake has been applied within the last 6 mins

Question 10

What is the function of the PTU?

Answer 10

Consists of a hydraulic pump in system 2 driven by a hydraulic motor in system 1.

It assist the retraction or extension of the landing gear should the number 2 eng or EDP fail

Question 11

In Auto, when does the PTU activate?

Answer 11

Flaps not set to zero or landing gear not up and locked
EDP1 not failed
Hydraulic reservoir 2 quantity above 12%

Question 12

What is the Hydraulic System 1 comprised of?

Answer 12

EDP, Electric Hydraulic Pump, Reservoir, Accumulator

Question 13

What systems does the HYD 1 system supply?

Answer 13

-Elevator (LH Outboard Actuators
-Rudder (Upper Actuator)
-Thrust Reverser ENG1
-Multi-Function Spoilers Left and Right Panels 3 & 4)
-Ground Spoilers (Left and Right Panel 2)
-Outboard Brake
-Emergency Parking Brake

Question 14

What is the Hydraulic System 2 comprised of?

Answer 14

EDP, Electric Hydraulic Pump, Reservoir, Accumulator, and PTU

Question 15

What systems are supplied by HYD SYS2?

Answer 15

-Elevators (LH & RH inboard actuators)
-Ailerons (Left and Right Inboard Actuators)
-Eng 2 Thrust Reverser
-Multi-function Spoilers (Left and Right Panels 5)
-Ground Spoilers (Left and right panel 1)
-Inboard Brake
-Nose Wheel Steering
-Landing Gear

Question 16

What does the Hydraulic System 3 comprise of?

Answer 16

Reservoir, 2 Electric Hydraulic Pumps, Accumulator

Question 17

What systems are supplied by the Hyd 3 Hydraulic system?

Answer 17

-Elevator (RH Outboard Actuators)
-Rudder (Lower Actuator)
-Ailerons (Left and Right outboard Actuators)

Question 18

At what temperature would the Electric Hydraulic Pumps in System 3 automatically switch off?

Answer 18

125 degrees

Question 19

What action would be required is Hyd _ Overheat Eicas Warning message comes up for any of the hydraulic systems?

Answer 19

The temperature has reached 145 degrees.

For HYD Sys 1 (2), Eng PUMP SHUTOFF Guarded switch must be pressed to close the SOV

For Hyd Sys 3, both Electric Pump A and Electric Pump B must be switch off using the respective Rotator Knobs

Question 20

What is the Primary power source for Hyd Sys 3?

Answer 20

Electric Pump 3A, which needs to be turned on, or off manually by flight crew when during engine start and shutdown respectively

Question 21

During an electrical emergency, what maintains power to the associated flight controls? When would this happen?

Answer 21

Hydraulic system 3 Accumulator

When the RAT is deployed

Question 22

What is the function of the Pump unloader valve in Hyd Sys 3?

Answer 22

It limits the discharge pressure on the AC Electric Pump 3A to reduce the torque, and therefore reduce the electrical power required to start the pump.

Question 23

What is the function of the flow limiter valve?

Answer 23

It reduces the flow provided by the electrical pump 3A, reducing the electrical power that the pump can draw, and prevent the electric pump from stalling the RAT.

Question 24

If, after shutting down the associated EDP/SOV in a HYD 1(2) overheat Eicas message, the message still persists, what is the QRH action?

Answer 24

Associated engine shutdown procedure

Question 25

You receive the HYD PTU Fail message on the Eicas, what is the QRH action?

Answer 25

PTU Knob - ON

If message persists:
PTU Knob - OFF

Question 26

You receive the HYD 1 (2) HI TEMP Eicas message. What does this mean, and what are the QRH actions?

Answer 26

The associated system hydraulic temperature has reached 125 degrees.

Turn off the associated Electric Hydraulic Pump

Question 27

HYD 3 HI TEMP EICAS message. QRH actions?

Answer 27

Hyd 3 Electric Pump A - OFF

Question 28

HYD 1 (2) LO PRESS EICAS message. QRH actions?

Answer 28

associated system ELEC PUMP KNOB - ON

Question 29

HYD 3 LO PRESS EICAS message. QRH actions?

Answer 29

Electric Pump 3B - ON
Electric Pump 3A - OFF

If message persists:
Electric Pump 3B - OFF

Question 30

What does the HYD 3 VLV FAIL message mean?

Answer 30

Both HYD 3 Valves, used during an Electrical emergency, have failed.

Pressure is maintained through the accumulator only, and therefore minimum 130KIAS must be maintained as this works with RAT deployment.