Hydraulics

Question 1

How many hydraulic systems does the aircraft have? And what are they?

Answer 1

Three.
(1) System A
(2) System B
(3) Standby

Question 2

Where are the hydraulic system fluid reservoirs located, and how are they pressurised?

Answer 2

They are located in the main wheel well area, and are pressurised using bleed air.

Question 3

Which system is the standby reservoir connected to?

Answer 3

System B.

Question 4

Will the engine-driven pump continue to rotate if the associated engine is operating?

Answer 4

Yes.

Question 5

What is the minimum fuel requirement for ground operation of the electric pumps?

Answer 5

760kgs in the associated main tank.

Question 6

If a leak develops in the System A hydraulic reservoir, how full is the indication with the fluid level at the top of the standpipe?

Answer 6

20% full.

Question 7

What is the purpose of the Power Transfer Unit?

Answer 7

To supply additional hydraulic fluid to operate the auto slats and leading edge flaps/slats at a normal rate.

Question 8

Which system does the PTU draw pressure from and to where?

Answer 8

Draws pressure from system A to help pressurise system B.

Question 9

What is the purpose of the Landing Gear Transfer Unit? And which system supplies this fluid?

Answer 9

To supply hydraulic fluid to raise the landing gear in the event of an engine #1 failure.
System B provides hydraulic fluid for System A.

Question 10

What type of pump does the standby hydraulic system use?

Answer 10

A single electric pump.

Question 11

Which systems is the standby hydraulic pump used to power?

Answer 11

(i) Thrust Reversers
(ii) Rudder
(iii) Extending Leading Edge Flaps/Slats
(iv) Standby Yaw Damper

Question 12

Does the Standby Hydraulic System provide extension or retraction of the leading edge flaps and slats?

Answer 12

Extension.

Question 13

What are the conditions for automatic operation of the Standby Hydraulic System?

Answer 13

•​ Loss of system A​ or B,​ and​
•​ Flaps extended,​ and​
•​ Airborne, or wheel speed greater than 60kt, and​
•​ FLT​ CONTROL​ switch A​ or​ B Hydraulic System ON

Question 14

How is manual operation of the Standby Hydraulic System achieved?

Answer 14

Positioning either​ FLT​ CONTROL​ switch to STBY​ RUD.

Question 15

If you select both FLT CONTROL switches to STBY RUD, which flight control surfaces have hydraulic power removed from them?

Answer 15

• Rudder
• Ailerons
• Elevators

Question 16

Which system powers the trailing edge flaps?

Answer 16

System B.

Question 17

How does selecting the Alternate Flaps master switch to ARM affect the trailing edge flaps?

Answer 17

Isolates them from the hydraulic system.

Question 18

When does the LOW QUANTITY light illuminate for the Standby Hydraulic System?

Answer 18

At approximately half full.

Question 19

What quantity will System B indicate eventually if a leak occurs?

Answer 19

Zero