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SAI 737-800 (2021) > Hydraulics > Flashcards

Flashcards in Hydraulics Deck (36)
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1
Q

Electric Hydraulic Pump OVERHEAT Lights

A

Illuminated: Hydraulic fluid used to cool and lubricate the corresponding electric driven pump has overheated or the pump itself has overheated

2
Q

Hydraulic Pump LOW PRESSURE Lights

A

Illuminated: output pressure of associated pump is low

3
Q

ELECTRIC HYDRAULIC PUMPS switches

A

ON - provides power to associated electric motor-driven pump

OFF - electrical power removed from pump

4
Q

ENGINE HYDRAULIC PUMP switches

A

ON - deenergizes blocking valve in pump to allow pump pressure to enter system

NOTE: should remain ON at shutdown to prolong solenoid life

OFF - energizes blocking valve to block pump output

5
Q

Normal and Max pressure for the hydraulic system pressure

A

Normal: 3000psi
Max: 3500 psi

6
Q

When will you get a REFILL indication for hydraulics?

A

76%

7
Q

FLIGHT CONTROL switches

A

STBY RUD: activates standby pump and opens standby rudder shutoff valve to pressurize standby rudder power control unit

OFF: closes flight control shutoff valve isolating ailerons, elevators, and rudder from associated hydraulic system pressure

ON: (guarded postion) normal operating postion

8
Q

Flight Control (LOW PRESSURE) lights

A

Illuminated:

Indicates low hydraulic system (A OR B) pressure to ailerons, elevator and rudder

deactivated when associated FLIGHT CONTROL switch is positioned to STBY RUD and standby rudder shutoff valve opens

9
Q

STANDBY HYDRAULIC LOW QUANTITY light

A

Illuminated: Indicates low quantity in standby hydraulic reservoir

always armed

10
Q

STANDBY HYDRAULIC LOW PRESSURE LIGHT Light

A

Illuminated:

  • indicates output pressure of standby pump is low
  • armed only when standby pump operation has been selected or automatic standby function is activated
11
Q

ALTERNATE FLAPS master switch

A

OFF - normal operating position

ARM - closes trailing edge flap bypass valve, activates standby pump, and arms ALTERNATE FLAPS position switch

12
Q

STBY RUD ON light

A

illuminated:

- indicates the standby hydraulic system is commanded on to pressurize the standby rudder power control unit

13
Q

How many hydraulic systems?

A

A / B / standby

14
Q

What does the hydraulic systems power?

A
Flight controls
Leading edge flaps and slats
Trailing edge flaps
landing gear
wheel brakes
nose wheel steering
thrust reversers
autopilots
15
Q

Can only A or B power all flight controls?

A

yes

16
Q

System A and B are pressurized from the ?

A

Bleed Air

17
Q

The standby system is pressurized from?

A

via the reservoir in system B

18
Q

System A powers?

A
Ailerons
rudder
elevator
flight spoilers (two on each wing)
ground spoilers
alternate brakes
NO.1 thrust reverser
Autopilot A
normal nose wheel steering
landing gear
PTU
main deck cargo
19
Q

System B powers?

A
ailerons
rudder
elevator and elevator feel
flight spoilers (two on each wing)
leading edge flaps and slats
trailing edge flaps
normal brakes
NO.2 thrust reverser
Autopilot B
alternate nose wheel steering
landing gear transit unit
autoslats
yaw damper
20
Q

How many pumps are in each system?

A

2: 1 engine pump and 1 AC electric motor driven pump

21
Q

Min fuel for ground operation of electric motor-driven pumps is ?

A

1675lbs in the realted main tank

22
Q

System A hydraulic leak associated with the engine driven pump leaves how much fluid left?

A

a standpipe prevents total system fluid loss.

with fluid at the top of the standpipe, the reservoir has about 20% fluid left

23
Q

System B hydraulic leak will result in what?

A

A leak in either pump, line, or component of system will result in a decrease of quantity till 0 and the system b pressure is lost.

  • There will remain enough fluid for PTU operation
  • A leak in system B will not affect the operation of standby system
24
Q

What is the purpose of the PTU

A

to supply additional volume of hydraulic fluid needed to operate the autoslats and leading edge flaps and slats at the normal rate when system B engine-driven hydraulic pump volume is lost.

25
Q

How is the PTU powered?

A

the PTU is powered by system A to power a hydraulic motor-driven pump which pressurizes the system B hydraulic fluid

26
Q

When will the PTU operate automatically?

A

system B engine-driven pump hydraulic pressure drops below limits

airborne

flaps are less than 15 but not up

27
Q

What is the purpose of the landing gear transfer unit?

A

the purpose is to supply the volume of hydraulic fluid needed to raise the landing gear at the normal rate when system A engine-driven pump volume is lost

28
Q

When will system B engine driven pump supply hydraulic fluid to operate the landing gear transfer unit?

A

Airborne
NO.1 engine RPM drops below a limit value
landing gear lever is positioned UP
either main landing gear is not up and locked

29
Q

The standby system can be activated how and uses a single electric motor-driven pump to power what?

A
Manually or automatically
------
thrust reverses
rudder
leading edge flaps and slats (extend only)
standby yaw damper
30
Q

Positioning either FLT CONTROL switch to STBY RUD does what? (MAN OPS OF STANDBY SYSTEM)

A
  • activates the standby electric motor-driven pump
  • shuts off the related hydraulic system pressure to ailerons, elevators and rudder by closing the flight control shutoff valve
  • opens the standby rudder shutoff valve
  • deactivates the related flight control LOW PRESSURE light when the standby rudder shutoff valve opens
  • allows the standby system to power the rudder and thrust reversers
  • illuminates the STBY RUD ON, Master Caution, and Flight Controls (FLT CONT) lights
31
Q

ALTERNATE FLAPS master switch to ARM (MAN OPS OF STANDBY SYSTEM)

A
  • activates the standby electric motor-driven pump
  • closes the trailing edge flap bypass valve
  • arms the ALTERNATE FLAPS position switch
  • allows the standby system to power the leading edge -
    flaps and slats and thrust reversers
32
Q

What conditions cause the automatic operation of the STANDBY HYDRAULIC system

A
  • Loss of system A or B and
  • flaps extended and
  • airborne, or wheel speed greater than 60kts and
  • FLT CONTROL swith A or B HYD system ON

or

the main PCU Force flight monitor trips

33
Q

Automatic operating of the standby system does what?

A
  • activates the standby electric motor-driven pump
  • opens the standby rudder shutoff valve
  • allows the standby system to power the rudder and thrust reversers
  • illuminates the STBY RUB ON, Master caution, and FLT CONT lights
34
Q

What happens if there is a leak in the Standby Hydraulic system?

A

the reservoir decreases to zero

35
Q

When do variations in hydraulic quantity indications occur?

A
  • the system becomes pressurized after engine start
  • raising or lowering the landing gear or leading edge devices
  • cold soaking occurs during long periods of cruise
36
Q

REVERSER LIGHT

Triggers MASTER CAUTION (ENG) / Acronym (ATIS)

A

AUTO-RESTOW circuit has be activated in flight

TR Sleeves not in commanded state (1 or more)

Isolation Valve not in commanded position

Sync-lock circuit failure has been detected