Hydraulic System

Question 1

What is the T-6 hydraulic system pressurized to?

Answer 1

3000 +- 120 psi

Question 2

What devices does the primary hydraulic system operate in normal flight operations?

Answer 2

• Landing gear and main landing gear inboard doors
• Flaps
• Speed brake
• Nose wheel steering

Question 3

Where are most of the hydraulic system components located?

Answer 3

Hydraulic service bay on the lower right side just behind the wing

Question 4

At what pressure will the hydraulic system allow operation?

Answer 4

> 1800 psi

Question 5

What is the purpose of the engine-driven pump?

Answer 5

Creates and distributes pressure to the hydraulic system

Question 6

What is the purpose of the reservoir?

Answer 6

Provides pressurized fluid back to the pump to the keep the pump “charged” with fluid

Question 7

What is the purpose of the reservoir piston?

Answer 7

Steps down the return side of the reservoir to 50 psi to prevent damage to the pump

Question 8

What is the purpose of the reservoir cylinder?

Answer 8

Prevents foaming of the fluid due to low pressure, maintains 50 psi in the reservoir

Question 9

What is the purpose of the Pressure Release Valve?

Answer 9

Helps avoid any damage caused by hydraulic overpressure

Question 10

What psi does the pressure release valve operate at?

Answer 10

3250 to 3500 psi

Question 11

What is the purpose of the slide valve?

Answer 11

Isolate the hydraulic pressure coming from the engine-driven pump, through the power package, from the rest of the hydraulic system when the emergency system is activated

Question 12

What will activate the emergency hydraulic system?

Answer 12

Pulling the landing gear emergency extension handle

Question 13

Can you return to normal operation once the landing gear emergency extension handle is pulled?

Answer 13

No, maintenance must reset the handle and emergency selector manifold

Question 14

What is the purpose of the selector manifold?

Answer 14

Operates the appropriate electrical selector valve

Question 15

What are normal operating limits for hydraulic pressure?

Answer 15

2880 to 3120 psi

Question 16

What happens if the hydraulic fluid level in the reservoir drops below one quart?

Answer 16

• The amber HYDR FL LO annunciator illuminates
• MASTER CAUTION illuminates
• Aural tone

Question 17

When will the emergency system be used?

Answer 17

• In the event of a primary hydraulic system failure
• In the event of engine failure
• In the event of battery bus failure

Question 18

What does the emergency system allow?

Answer 18

A one-time lowering of the landing gear and main gear inboard doors, and the flaps

Question 19

When is the emergency package pressurized?

Answer 19

At engine startup

Question 20

What happens if the emergency accumulator drops below 2400 +- 150 psi?

Answer 20

• Amber EHYD PX LO annunciator illuminates
• MASTER CAUT
• Aural tone

Question 21

How is power provided for the landing gear?

Answer 21

LDG GR CONT circuit breaker on the batter bus in the front cockpit

Question 22

Approximately how long does it take for normal gear extension/retraction?

Answer 22

6 seconds

Question 23

What airspeed must you be below to operate the landing gear and/or flaps?

Answer 23

150 KIAS

Question 24

What kind of flaps does the T-6 use?

Answer 24

Split flaps, inboard and outboard

Question 25

What are flaps used for?

Answer 25

Produce an increase or decrease in lift and drag

Question 26

Which flap setting will give you the greatest amount of lift with the least amount of drag?

Answer 26

Takeoff

Question 27

What provides power to the flap system?

Answer 27

FLAP CONT circuit breaker on the battery bus in the front cockpit

Question 28

What has to happen before emergency flaps can be used?

Answer 28

The emergency landing gear handle must have been activated

Question 29

What powers emergency flap operation?

Answer 29

Hot battery bus

Question 30

What is the purpose of the speed brake?

Answer 30

- Decelerate | - Increase descent rate without increasing airspeed

Question 31

What provides power to the speed brake?

Answer 31

SPEED BRAKE circuit breaker on the generator bus

Question 32

When will the speed brake not extend?

Answer 32

If the flaps are already extended

Question 33

Once extended, the speed brake will remain so until what happens?

Answer 33

- Speed brake switch is moved forward - Flaps are extended to TO or LDG position - PCL moved to MAX

Question 34

What provides power to the nose wheel steering system?

Answer 34

NWS circuit breaker on the generator bus in the front cockpit

Question 35

How far will the nose wheel move with NWS off?

Answer 35

80° in either direction

Question 36

How far will the nose wheel move with NWS on?

Answer 36

12° in either direction