Hydraulic System: General Flashcards Preview

Lear 45/40XR Initial Training > Hydraulic System: General > Flashcards

Flashcards in Hydraulic System: General Deck (24):
1

Main components of the system?

1. 1 Reservoir
2. 3 Pumps
3. Manifolds
4. Control and Shut-Off Valves
5. 2 Accumulators (Main system/Brake)

2

What does the hydraulic system operate?

1. Landing Gear
2. Landing Gear Doors
3. Brakes
4. Flaps
5. Spoilers/Spoilerons
6. Thrust Reversers

3

How many hydraulic pumps does the system have?

1. (2) Engine-Driven Pumps
2. (1) 28VDC Auxiliary pump

4

What can the Auxiliary Pump operate in the event of the main system fail?

1. Landing Gear
2. Flaps
3. Backup Brake

5

Type of hydraulic fluid and how much can it hold?

- MIL-H-5606
- 7.3 Quartz

6

Is the reservoir pressurized?

Yes

7

How is the reservoir pressurized and how much psi is that?

- Through engine bleed air
- Approx. 24 psi.

8

Does the reservoir have excessive pressure protection and what psi?

- Overboard relief valve vents and vacuum relief vent
- Approx. 26.5 psi.
- > 340°F thermal shut-off valve closes

9

What does "HYD XFLOW" provide?

- Auxiliary hydraulic power to:
1. Landing Gear
2. Flaps
3. Brake Accumulator

10

What is the normal pressure of the system?

- 3,000 psi.

11

What is the maximum output of each engine driven pump?

- 4.6 Gal/min

12

How much psi. does the engine drive pumps maintain?

- 2,210 to 3,600 psi.

13

How much psi. does the aux. pumps maintain?

- 2,610 to 3,600 psi.

14

What is the maximum output of each auxiliary pump?

- 1.0 Gal/min

15

Why is the reservoir split into two sections?

- Redundancy
- One side for engine-driven pumps
- Another side for auxiliary pumps

16

What happens when the auxiliary pump is used for more than 20 minutes?

- Volume reduced to .75 Gal/min
- Psi is reduced to 2,850 psi.

17

What are the automatic auxiliary pump operations?

1. Pump comes off when aircraft is on
2. Pump comes off when gear handle is selected UP
3. Pump comes on when gear handle is selected DOWN
4. Pump comes off when aircraft is powered down

18

At what psi. would you receive an EICAS indication?

- 1,900 psi. or less

19

What provides hydraulic pressure status on the EICAS?

- Transducer located on the main filter manifold

20

When will the EICAS indicate HYD PUMP LO?

- Pump output pressure is < 1,900 psi. for more than 5 seconds

21

The main system status turns amber when?

- <1,500 psi. or >3,600 psi.

22

The B-Accumulator status turns amber when?

- <1,200psi. or >3,600 psi.

23

What do you lose when you have no main hydraulic pressure?

1. Spoilers/Spoilerons
2. Thrust Reversers
3. Main system (accumulator)

24

Why is it recommended to alternate engine starts?

- Only way to check the engine driven pump output