HYDRAULIC SYSTEM

Question 1

How many hydraulic systems does the E170 have?

Answer 1

3

Question 2

Consumers of hydraulic

Answer 2

1) Primary and secondary flight controls

2) Landing Gear

3) Brakes

4) Nose Wheel steering

5) Thrust reversers

Question 3

Nominal pressure

Answer 3

3000 psig

Question 4

Main components of hydraulic system

Answer 4

1) 2 engine driven pumps

2) 4 electric hydraulic pumps

3) 1 PTU

4) 3 hydraulic reservoirs

Question 5

Sources of pressure for system 1/2 — main and backup

Answer 5

Main — Engine driven pumps

Backup — AC electrical pump

Question 6

Sources of pressure for system 1/2 — main and backup

Answer 6

Main — Engine driven pumps

Backup — AC electrical pump

Question 7

When is an electric pump used? (Normal and abnormal)

Answer 7

During takeoff and landing

In case of engine / engine-driven pump failure

Question 8

Where is the PTU installed? The purpose of PTU?

Answer 8

Between system 1 and 2

Purpose — to transfer the power between systems without mixing the fluid (for landing gear only)

Question 9

Source of system 3 power — main and auxiliary

Answer 9

Main electric pump (main)

Auxiliary electric pump (backup)

Question 10

PTU operations limitations?

Answer 10

PTU activation is inhibited if:

1) on ground

2) airspeed < 50 kt

Question 11

Philosophy of redundancy of hydraulic system parts

Answer 11

In case of failure of even two system, no critical control functions will lost

Question 12

Location of HS1 installation?

Answer 12

Left center fuselage bay

Question 13

HS1 consumers

Answer 13

1) ELEV OUTBD LH
2) RUD UPPER
3) ENG 1 REVERSER
4) MF SPOILERS 3/4
5) GND SPOILER 2
6) OUTBD BRAKES

7) EMER PARK BRAKE

Question 14

HS2 consumers

Answer 14

1) ELEV INBD
2) AIL INBD
3) ENG 2 REVERSER
4) MF SPOILER 5
5) GND SPOILER 1
6) BRAKE INBD
7) NOSE WHEEL STEERING

8) EMER/PARK BRAKE

9) LANDING GEAR

Question 15

Location of HS2 installation?

Answer 15

Right center fuselage bay

Question 16

Location of HS2 installation?

Answer 16

Right center fuselage bay

Question 17

Location of HS3 installation?

Answer 17

In the aft fuselage

Question 18

HS3 consumers

Answer 18

1) ELEV OUTBD RH
2) RUD LOWER
3) AIL OUTBD

Question 19

ELEC PUMP 1/2 or 3 — AUTO logic

Answer 19

Elec pumps 1/2 turn ON automatically

1) during takeoff and landing

2) in case of MAIN PUMP

Elec pump 3 B turns on automatically

1) 3 A pump failure (INHB during TO/LDG)

Question 20

PTU activation logic

Answer 20

In case of engine 2 failure during TO or LDG

FLAPS ARE NOT SET TO 0

Question 21

What provides electric pumps control?

Answer 21

AUTO — SPDU

ON — DIRECT ELECTRICAL CONNECTION FROM CKPT TO ACTUATORS

Question 22

Conditions of starting ELECTRICAL PUMPS 1/2/3

Answer 22

1/2:
— FLAPS greater than 0 degrees
— TLs set to TO thrust or GS > 50 kts

1:
— EDP is not operational

2:
— EDP 2 is not operational

3B:
— 3A PUMP is not operational

Question 23

How is the 3A pump power provided in case of engine failure?

Answer 23

1) 3A pump will initially turns off due to a loss of electrical power

2) System Accumulator will provide pressure to flight controls until RAT is deployed and energized

Question 24

Purpose of pressure accumulator?

Answer 24

1) maintains constant pressure

2) keeps residuals pressure in reservoir to avoid pump cavitations

HYD SYS 3:

1) provides hydraulic to flight controls from the beginning of RAT deployment until 3A PUMP is AC powered

Question 25

Conditions of AC pump start

Answer 25

In flight:
— EDP/ENG FAIL
— FLAPS > 0
+ 60 s during landing

On ground:
— FLAPS > 0
— TL’s set to T/O thrust or GS > 50 kts
+ 60 s during takeoff

+ AC PUMP 2:
— ENG 1 started & PARK BR released
— Durnig ENG 1 start (N2 > 40%) if PARK BR has been applied within last 6 min

AC PUMP 2 automatically turns OFF after 6 minutes elapsed from PARK BR application

Question 26

PTU logic (OFF-AUTO-ON)

Answer 26

PTU will automatically turn ON if:
— ENG/EDP 2 fail
— FLAPS > 0
— ENG/EDP 1 NOT FAIL
— Fluid Quantity 2 > 12%

!!! Activation on ground is inhibited

Question 27

HYD SYS 3: PUMP UNLOADER VALVE & FLOW LIMITER VALVE

Answer 27

In case of electrical emergency avoid overload in the RAM:

1) PUMP UNLOADER — reduces pressure of pump during its start-up

2) FLOW LIMITER — reduces flow to decrease load on RAT