Hydraulics

Question 1

System 1 has

Answer 1

• 1 reservoir
• 1 engine driven pump (EDP)
• 1 AC motor pump (ACMP) used as a back up for the EDP
• 2 accumulator

Question 2

System 2 has

Answer 2

Same as system 1

• allows single engine taxi
• ACMP 2 to provide hydraulic power to nose wheel steering
• Inboard brakes
• PTU (power transfer unit) provides pressure to system 2

Question 3

System 3 has

Answer 3

• 1 reservoir
• 2 AC motor pumps (ACMP A and B)
• Pump A is primary
  
  • No AUTO position, pump is either On or OFF
• Pump B
  
  • Three positions OFF, AUTO and ON
  • AUTO, ACMP B will turn on AUTOM with Failure of ACMP A
• 1 Accumulator
• Electrical failure system 3 accumulator will provide hydraulic power to flight controls

Question 4

In flight

Answer 4

• System logic activates ACMP in case of
• EDP failure
• Flaps selected to any position greater than 0

Question 5

On the ground

Answer 5

• System logic activates ACMP in case of
  
  • Flaps selected to any position greater than 0 degrees
  • Thrust levers set to takeoff thrust or groundspeed greater than 50 Knots

Question 6

Accumulators

Answer 6

• System 1 and 2 Shock absorption
• Another accumulator for emergency parking brake
• System 3 has 1 accumulator electrical emergency provides hydraulics to flight controls

Question 7

How many applications for the brakes with the brake accumulator?

Answer 7

• 6 total application

Question 8

What does the PTU (power transfer unit) for?

Answer 8

• The PTU assists landing gear extension and retraction in the event Engine driven hydraulic pump 2 fails, Engine 2 fails.
• Requires no AC power

Question 9

When would you take ACMP 1 control out of AUTO to ON?

Answer 9

• When taxing with Engine 2 running only.

Question 10

When ACMP 1 is set on AUTO what does it do?

Answer 10

• Turns pumps on automatically for
  
  • T/O 50 kts ground speed or Thrust levers TOGA
  • Landing (flaps greater than 0)
  • Or EDP (engine driven pump) failure

Question 11

When ACMP 2 is in AUTO what is controlled?

Answer 11

• Turns on automatically when
  
  • Single engine taxi if engine 1 is running
  • parking break released or set within 6 min
  • T/O 50 kts ground speed or Thrust levers TOGA
  • Landing flaps greater than 0
  • EDP (engine driven pump) Failure

Question 12

When is ACMP 3A on or off?

Answer 12

• Turned ON before engine start and OFF after engine shut down.

Question 13

ACMP 3B in AUTO does what?

Answer 13

• Automatically turns the pump ON if 3A fails inflight. Stays in AUTO

Question 14

Minimum reservoir temp for ENG Start?

Answer 14

-18 degrees C