Utility hydraulics

Question 1

1. What is the purpose of the utility hydraulic system?

Answer 1

primarily used for ground operations

Question 2

2. What are the sub-systems that are operated by the utility hydraulic system?

Answer 2

Power xfer unit, APU start system, ENG start system, Cargo ramp, power steering, swivel locks, wheel brakes, center cargo hook, cargo winch/rescue hoist

Question 3

(1) Hydraulic service module.

Answer 3

near ramp on #2 side. used to refill hydraulic system.

Question 4

(2) Utility Reservoir/Cooler assembly.

Answer 4

aft pylon hydraulic compartment, cools hydraulic fluid

Question 5

(3) Utility Reservoir Pressurization Accumulator. (Pre-flt pressure 2500-3500 or 3000 psi)

Answer 5

maintains pressure on utility reservoir/cooler assembly next to utility reservoir

Question 6

(4) Utility System Hand pump.

Answer 6

next to ramp #2 side, used to re-pressurize start accumulator

Question 7

(5) Electric Pump for the Utility System Hydraulic Accumulator (EPUSHA).

Answer 7

next to system hand pump, electrically recharges start accumulator

Question 8

(6) APU Start Accumulator. (Pre-flt pressure 2500-3500 or 3000 psi)

Answer 8

2 side above ramp, used to hold hydraulic pressure to start APU

Question 9

(7) Auxiliary Power Unit (APU) Motor/Pump.

Answer 9

On the APU to start turbine and above 90% work as a pump to create pressure

Question 10

(8) APU Start Module. (Pre-flt pressure 2500-3500 or 3000 psi)

Answer 10

2 side above ramp, Stops the start accumulator from discharging

Question 11

(9) Utility Hydraulic Aft Transmission Driven Pump.

Answer 11

located of aft transmission, main pump to provide pressure to hydraulic system

Question 12

(10) Flight Hydraulic Power Transfer Unit (PTU).

Answer 12

located in forward and aft pylon, provide pressure for flight control hydraulic system.

Question 13

(11) Auxiliary Ground Power Unit (AGPU).

Answer 13

not on the aircraft, provides pressure and electricity as needed

Question 14

(12) Utility Hydraulic Pressure Control Module.

Answer 14

on #1 side above ramp, controls where hydraulic pressure is sent and filters fluid also monitors pressure

Question 15

(13) Utility Hydraulic Return control module.

Answer 15

2 side above ram, filters return fluid and gathers fluid from systems

Question 16

(14) Brake Accumulator

Answer 16

forward pylon, holds pressure emergency brake applications

Question 17

(15) Power Steering Module.

Answer 17

2 side on wall near ramp, for emergency swivel lock operation

Question 18

(16) Utility Hydraulic Control Panels.

Answer 18

located on overhead console, used to control pressure to subsystems (check for systems)

Question 19

(17) Maintenance panel.

Answer 19

2 side on wall next to ramp, shows system information for all hydraulic systems

Question 20

4. What are the four sources of pressure for the utility hydraulic system?

Answer 20

APU start accumulator, APU motor pump, Utility hydraulic system pump, AGPU

Question 21

1. When can the fill module be used to add fluid to the hydraulic systems?

Answer 21

on ground or in flight

Question 22

2. What could happen if the fluid level is allowed to go below the sight glass while using the fill module?

Answer 22

you will start pumping air into the hydraulic system

Question 23

3. What is the purpose of the visual fluid indicator on the hydraulic reservoir?

Answer 23

to let you know if you need to add fluid to the system

Question 24

4. What should the gauge indication be on the utility reservoir pressurization accumulator be during pre-flt?

Answer 24

in the green band

Question 25

5. When should a pilot use the utility reservoir depressurization valve?

Answer 25

never

Question 26

6. Why should EPUSHA operations not exceed five?

Answer 26

it will kill the battery

Question 27

7. What should the pressure indicate during pre-flt on the APU start accumulator?

Answer 27

3,000 PSI

Question 28

8. What is the Emergency Utility Pressure Valve used for and what position should the valve be in during pre-flt?

Answer 28

NORMAL, allows the APU start accumulator or hand pump to pressurize system

Question 29

9. What should the pressure indicate during pre-flt on the APU start module accumulator?

Answer 29

approx. 3,000 PSI

Question 30

10. When would the APU motor pump be used during flight?

Answer 30

when the transmission driven utility pump fail during flight

Question 31

11. What component provides the utility hydraulic systems pressure in flight, under normal conditions?

Answer 31

utility hydraulic pump

Question 32

12. What provides the utility hydraulic pressure indications to the crew?

Answer 32

the pressure control module

Question 33

13. What should be checked on the pressure control module during pre-flt?

Answer 33

general condition and security

Question 34

14. What should be checked on the return control module during pre-flt?

Answer 34

general condition and security

Question 35

15. What indications are provided on the maintenance panel for the utility hydraulic system?

Answer 35

pressure, temp, reservoir level, filter change, pump fault