Hydraulic

Question 1

What is powered by the left hydraulic system

Answer 1

• Primary flight controls
• Left thrust reverser

Question 2

What is powered by the right hydraulic system

Answer 2

• Primary flight controls
• Normal brakes
• Right thrust reverser

Question 3

What is powered by the center hydraulic system

Answer 3

• Primary flight controls
• Secondary flight controls (Flaps and slats)
• Alternate/reserve brakes
• Nose gear steering
• Main geer steering
• Landing gear actuation

Question 4

What does the RAT power (Electrically and hydraulically)

Answer 4

Electrically - the C1 and C2 TRU

Hydraulically - Center primary controls

Question 5

How are alternate/reserve brakes operated

Answer 5

Automatically. The C1 pump isolates its self from remaining system using fluid from below the stand pipe for alternate brakes and nose wheel steering.

Question 6

What does the fault light for each hydraulic pump indicate

Answer 6

OFF HOTLOP
- Switch is OFF
- HIGH OIL TEMP
- LOW OIL output PRESSURE

Question 7

Will the right demand pump operate continuously on the ground?

Answer 7

Yes, to provide backup pressure for normal brakes in case of engine driven pump failure

Question 8

Will the left demand pump operate continuously on the ground?

Answer 8

No, only for takeoff and landing to provide a backup for primary flight controls on take off

Question 9

How are hydraulic pumps load shed on the ground

Answer 9

C2 pump will load shed when
- C1 pump is ON
- Single source of external power
- APU only is running

Question 10

How are hydraulic pumps load shed in the air

Answer 10

C2 pump is load shed when
- All other pumps are operating
- Single source of electrical power
- Generator capacity is exceeded

Question 11

With low center system fluid quantity what happens >60kts

Answer 11

• Alternate brakes isolated from center system and remain operable using reserve fluid.
• Nose gear steering and actuation is isolated.
• Leading edge slats inhibited from working in PRIMARY mode (Hydraulic)

Question 12

When is nose gear steering reconnected

Answer 12

• Airspeed below 60KIAS, or
• Hydraulic pressure to the center system flight controls goes low, or
• The landing gear is selected down, both engines operating and engine pumps providing pressure.

Question 13

When will the RAT deploy automatically
(BAH)

Answer 13

• Both engines have failed and center low pressure
• Both AC transfer buses are unpowered
• All 3 Hydraulic systems low pressure

Question 14

What is the pressure output of the RAT (provides pressure for approximately half the center system)

Answer 14

1500psi

Question 15

What does the UNLKD light on the RAT switch mean

Answer 15

The RAT is not stowed

Question 16

What does the PRESS light on the RAT mean

Answer 16

The RAT is providing hydraulic pressure at 1500psi

Question 17

Can the RAT be manually deployed on the ground?

Answer 17

Yes

Question 18

When are leading edge slats reconnected to the center hydraulic system

Answer 18

• Center fluid recovers to normal for 5 seconds and
• System determines the BOTH engines have been running for 30 seconds

Question 19

What is required for Manual RAT deployment

Answer 19

• Hot battery bus or APU battery powered

Question 20

What output has priority for the RAT

Answer 20

Hydraulic, Electrical output will be load shed at low RPM

Question 21

How is system quantity displayed on the synoptic page

Answer 21

As a percentage of full
1.00 = 100%
LO = Quantity is low (Only displayed in flight)
RF = Refill (Only displays on the ground)
OF = Overfull (Only displays on the ground)