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Flashcards in Hydraulics Deck (35)
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1
Q

HYD: Ground spoilers

A

System A

2
Q

HYD: What is the difference in supply volume between engine and electric hyd pumps?

A

Engine driven pumps supply approximately 6 times the fluid volume of the related electric motor-driven pump

3
Q

HYD: Yaw damper

A

System B

4
Q

HYD: Describe a system B electric driven pump leak

A

Indicated quantity decreases to 0 and pressure is lost. However a standpipe ensures sufficient quantity for PTU operation.

5
Q

HYD: Landing gear

A

System A

6
Q

HYD: REFILL indication (RF) (white) appears

A

Hydraulic quantity below 76%

Note: valid only when aircraft is on ground with both engines shutdown or after landing with flaps up during taxi-in

7
Q

HYD: Rudder

A

System A/B

8
Q

HYD: Alternate brakes

A

System A

9
Q

HYD: Autopilot B

A

System B

10
Q

HYD: Hydraulic A/B pressure minimum

A

2,800 psi

11
Q

HYD: FLT CONTROL switches - describe STBY RUD position

A
  • closes flight control shutoff valve
  • corresponding HYD system pressure is isolated from aileron, elevator feel and rudder
  • activates sby pump (arms sby hyd LOW PRESSURE light) and pressurises the sby rudder PCU
  • illuminates the STBY RUD ON light
  • thrust reverser will be powered by sby hyd system if necessary
  • yaw damper switch can be turned back on if both switches are placed in STBY RUD
12
Q

HYD: Describe the Power transfer unit

A

Supplies the additional volume of hyd fluid needed to operate autoslats and leading edge flaps and slats at normal rate when sysB eng-driven hyd pump volume is lost.

Uses sys A pressure to power a hyd motor driven pump which pressurises sys B hyd fluid.

Operates when all the following conditions exist:

Sys B eng-driven pump hyd press below limits
Airborne
Flaps Less than 15 but not up
SFP flaps not up

13
Q

HYD: Brake pressure minimum

A

2,800 psi

14
Q

HYD: Flight spoilers

A

System A / System B

Two on each wing for A / B

15
Q

HYD: FLT CONTROL switches - describe position OFF

A
  • closes flight control shutoff valve
  • corresponding HYD system pressure is isolated from aileron, elevator feel and rudder
  • yaw damper switch flips off when B system switch selected OFF
  • respective LOW PRESSURE and FEEL DIFF PRESSURE light illuminate
16
Q

HYD: No. 2 thrust reverser

A

System B

17
Q

HYD: Describe a system A electric driven pump leak

A

Fluid quantity decreases to 0 and all pressure is lost.

18
Q

HYD: Power transfer unit (PTU)

A

System A

19
Q

HYD: Describe a system A engine driven pump leak

A

Standpipe in the reservoir prevents total system fluid loss. With fluid level at the top of the standpipe, the reservoir quantity indicates approx 20%. System A pressure is maintained by the electric pump

20
Q

HYD: Trailing edge flaps

A

System B

21
Q

HYD: Ailerons

A

System A/B

22
Q

HYD: Normal nose wheel steering

A

System A

23
Q

HYD: Alternate nose wheel steering

A

System B

24
Q

HYD: Autopilot A

A

System A

25
Q

HYD: Leading edge flaps and slats

A

System B

26
Q

HYD: Autoslats

A

System B

27
Q

HYD: No. 1 thrust reverser

A

System A

28
Q

HYD: FLT CONTROL switches - describe position ON

A

(Guarded position)

  • normal operating position
  • opens flight control shutoff valve to aileron, elevator feel and rudder
29
Q

H

Elevator and elevator feel

A

System A / B

30
Q

HYD: Minimum fuel for ground operation of electric hydraulic pumps

A

760 kgs in related main tank

31
Q

HYD: Landing gear transfer unit

A

System B

32
Q

HYD: Describe a system B engine driven pump leak

A

Indicated quantity decreases to 0 and pressure is lost. However a standpipe ensures sufficient quantity for PTU operation.

33
Q

HYD: Normal bakes

A

System B

34
Q

HYD: Standby hydraulic system powers:

A

Thrust reversers
Rudder
Leading edge flaps and slats (extend only)
Standby yaw damper

35
Q

HYD: Describe landing gear transfer unit

A

Supply the volume of hyd fluid needed to raise the gear at the normal rate when sys A eng-driven pump volume is lost. Sys B eng-driven pump supplies the volume of hyd fluid needed to operate the landing gear transfer unit when all the following conditions exist:

Airborne
No. 1 engine RPM drops below a limit value
Landing gear lever up
Either main landing gear not up and locked