HYDRAULIC

Question 1

When does the Blue pump operate

Answer 1

• after the first engine is started

Question 2

PTU operation in AUTO

Answer 2

• differential pressure of 500 psi between GREEN and YELLOW
• after the first engine start until the second engine start, unless inhibited

Question 3

When is the PTU inhibited?

Answer 3

• on the ground with master switches split AND either the nose wheel steering disconnected OR the parking brake ON
• also during and for 40 seconds after cargo door operation

Question 4

ENG 1 (2) PUMP pb FAULT

Answer 4

• reservoir level low
• reservoir overheat
• reservoir air pressure low
• pump pressure low (inhibited on the ground with the engine stopped)

This light goes out when the crew selects OFF, except during an overheat. The light stays on as long as the overheat lasts.

Question 5

YELLOW ELEC PUMP pb FAULT

Answer 5

• reservoir level low
• reservoir overheat
• reservoir air pressure low
• pump pressure low
• pump overheat

This light goes out when the crew selects OFF, except during an overheat. The light stays on as long as the overheat lasts.

Question 6

BLUE ELEC PUMP pb FAULT

Answer 6

• reservoir level low
• reservoir overheat
• reservoir air pressure low
• pump pressure low (inhibited on the ground with the engine stopped)
• pump overheat

This light goes out when the crew selects OFF, except during an overheat. The light stays on as long as the overheat lasts.

Question 7

PTU pb FAULT

Answer 7

• GREEN or YELLOW overheat
• GREEN or YELLOW reservoir low air pressure
• GREEN or YELLOW reservoir level low

This light goes out when the crew selects OFF, except during an overheat. The light stays on as long as the overheat lasts.

Question 8

HYD priority valves

Answer 8

Removes hydraulic power from the heavy users and protects the flight controls

Question 9

RAT drop

Answer 9

The flight crew can manually extend the RAT at any time with the RAT MAN ON pb.

The RAT extends automatically with the loss of AC BUS 1 and AC BUS 2

Question 10

What are some users of the YELLOW system?

Answer 10

Flaps

Nose wheel steering

Alternate brakes

ENG 2 thrust reverser

Question 11

What are some users of the GREEN system?

Answer 11

Landing gear

Normal Brakes

Slats and Flaps

ENG 1 thrust reverser

Question 12

What are some users of the BLUE system?

Answer 12

Emergency generator

Slats