29 Hydraulic

Question 1

Green hydraulic reservoir capacity?

Answer 1

14.5L

Question 2

Blue hydraulic reservoir capacity?

Answer 2

6.5L

Question 3

Yellow hydraulic reservoir capacity?

Answer 3

12.5L

Question 4

Which systems have an accumulator?

Answer 4

All three!

Question 5

What is the hydraulic system pressure normally? (and when supplied by the RAT?)

Answer 5

3000psi +/- 50psi

2500psi if supplied by RAT

Question 6

When does the pressure displayed on the HYD SD page turn amber?

Answer 6

<1450psi

Question 7

When does the PTU kick in?

Answer 7

With a difference of 500psi between Green/Yellow system

Question 8

What is the hydraulic fluid ignition point?

Answer 8

450degC

Question 9

Where does the air come from to pressurise the hydraulic reservoirs and why?

Answer 9

HP bleed from engine 1 and to prevent cavitation

Question 10

What are priority valves used for in the hydraulic system?

Answer 10

To cut off hydraulic power to heavy load users if hydraulic pressure in a system gets low

Question 11

Which hydraulic system has a hand pump and why?

Answer 11

Only the yellow, for the cargo door

Question 12

On the HYD SD page, what does the circle represent towards the bottom of the Green and Yellow systems?

Answer 12

The hydraulic fire shut off valve (controlled through FIRE PB)

Question 13

What do the squares on the HYD SD page system lines represent?

Answer 13

Engine 1 + 2 (G + Y) engine driven hydraulic pumps, and the blue electric pump

Question 14

Which are the heavy load users that the priority system can isolate?

Answer 14

Green: Landing Gear, Slats + Flaps
Blue: Emer Gen, Slats
Yellow: Flaps

Question 15

Which systems use green hydraulic pressure to operate?

Answer 15

Landing Gear
Slats and Flaps

Rev Eng 1
Normal Brakes

Yaw Damper 1
Rudder
Stabiliser
L Elevator
L + R Spoiler 1
L + R Spoiler 5
L + R Aileron
L + R Slat WTB
R Flap WTB

Question 16

Which systems use blue hydraulic pressure to operate?

Answer 16

Emer Gen
Slats

Rudder
L + R Flaps WTB
L + R Slats WTB
L + R Elevator
L + R Spoiler 3
L + R Aileron

Question 17

Which systems use yellow hydraulic pressure to operate?

Answer 17

Flaps

Nose Wheel Steering
Alternate/Parking Brake
Rev Eng 2
Yaw Damper 2
Rudder
Stabiliser
R Elevator
L + R Spoiler 2
L + R Spoiler 4
L Flap WTB

Question 18

Can systems be recovered in a green and yellow hydraulic system failure? How?

Answer 18

Engine driven pump fail? Possibly use yellow electric pump
Low reservoir air pressure? System recoverable at lower altitudes
Reservoir overheat? Useable for approach once cooled

Question 19

What are the key considerations for a green and yellow hydraulic system failure?

Answer 19

Stopping problem (landing distances almost triple)
Alternate law (direct law at gear down)
Gravity gear extension QRH
Flaps/slats locked QRH
Some systems may be recoverable

Question 20

Can systems be recovered in a blue and yellow hydraulic system failure? How?

Answer 20

Engine driven pump fail? Yellow electric pump or RAT for blue system
Low reservoir air pressure? System recoverable at lower altitudes
Reservoir overheat? Useable for approach once cooled

Question 21

What are the key considerations for a blue and yellow hydraulic system failure?

Answer 21

Normal law (but without autopilots)
Gravity gear extension QRH (to protect green)
Nose wheel steering is lost

Question 22

Can systems be recovered in a green and blue hydraulic system failure? How?

Answer 22

Blue electrical pump fail? RAT out
Low reservoir air pressure? System recoverable at lower altitudes
Reservoir overheat? Useable for approach once cooled

Question 23

What are the key considerations for a green and blue hydraulic system failure?

Answer 23

Handling problem (gear at 200kts)
Aircraft sluggish
Gravity gear extension QRH (at 200kts)
Flaps/slats locked QRH

Question 24

What should you turn off if you have a G hydraulic low level or low air pressure?

Answer 24

The PTU to prevent it overheating or damaging the other system, and the green engine 1 pump

Question 25

What should you turn off if you have a Y hydraulic low level or low air pressure?

Answer 25

The PTU to prevent it overheating or damaging the other system, the yellow engine 2 pump, and the yellow electric pump