Hydraulics

Question 1

What is normal system pressure?

Answer 1

3,000 psi.

Question 2

What is the normal reservoir quantity?

Answer 2

45-85%

Question 3

If the reservoir is outside of the normal range, what color will the digital quantity be displayed in?

Answer 3

White.

Question 4

Can hydraulic quantity be accurately read without the system energized?

Answer 4

No.

Question 5

What kind of hydraulic fluid do we use, and what color is it?

Answer 5

Skydrol, purple.

Question 6

If pump 1A or 2A fails, will the respective electric pumps activate automatically?

Answer 6

No.

Question 7

When will the electric pumps (ACMP) automatically activate?

Answer 7

With their respective switches in auto, at least one generator online, and the flap position greater than zero.

Question 8

Is system cooling provided for hydraulic system 3?

Answer 8

No.

Question 9

How are hydraulic systems 1 and 2 cooled?

Answer 9

Ram air in flight or a fan in the ram air duct while on the ground blow cooling air over the shared hydraulic heat exchanger in the aft equipment bay.

Question 10

If there is an engine driven pump problem, 1A or 2A, is the associated engine required to be shutdown?

Answer 10

No. A shutoff valve has been positioned between the pump and the reservoir to isolate the pump from the system.

Question 11

When will the HYD 1 or 2 HI TEMP caution be displayed?

Answer 11

When the temperature exceeds 96º C.

Question 12

When a powered system is displayed in white on the hydraulic system synoptic page, what is indicated?

Answer 12

The system is pressurized above 1,800 psi.

Question 13

What is indicated when a system is displayed in amber?

Answer 13

The system is pressurized less than 1,800 psi.

Question 14

What is indicated when a system is displayed in dim magenta?

Answer 14

The sensing system is receiving invalid data.

Question 15

Which pumps are not controlled by the hydraulic control panel?

Answer 15

Pumps 1A and 2A.

Question 16

How many total hydraulic pumps are there?

Answer 16

Six, four electric and two engine driven pumps.

Question 17

How can the engine driven shutoff valves be closed?

Answer 17

By pressing the associated L or R HYD SOV switchlight, or by pressing the associated engine fire switch.

Question 18

What powers hydraulic pump 3B?

Answer 18

Normally AC Bus 1, and it is hard wired to the ADG to be powered when the ADG is deployed.

Question 19

If the ADG is providing power to pump 3B, can it be manually turned off?

Answer 19

No, the switch will not work.

Question 20

WHat effect will a loss of hydraulic systems 2 and 3 have on the landing gear?

Answer 20

Manual gear extension is required, and the nose gear will not extend.

Question 21

What purpose does the accumulator serve?

Answer 21

It dampens ossillations in pressure.

Question 22

What is the normal accumulator charge?

Answer 22

1,500 psi.

Question 23

Which systems provide power to the brakes?

Answer 23

Systems 2 is the outboard brakes, 3 the inboard brakes.

Question 24

Which system provides power to nose wheel steering?

Answer 24

System 3.

Question 25

Describe how the hydraulic check is performed.

Answer 25

Select the hydraulic synoptic page on ED2 and position the switches as follows: 1B OFF, 3A ON, 3B OFF, 2B OFF (all down!). Check system 3 quantity and pressure. Reposition the switches as follows: 1B ON, 3A OFF, 3B ON, 2B ON (all up!). Check system 1, 2, and 3 pressure and quantity.

Engage the stab trim and look to see if the SSCU test activates on theh flight control synoptic page. Return the switches 1B, 3B, and 2B to AUTO, and move switch 3A to ON to resume normal operations (all down). When checking each system, be sure to verify that the asspciated hydraulic services are displayed in white.