Skyblue CBT hydraulic system

Question 1

what are the main components of the hydraulic system?

Answer 1

• pumps
• accumulators
• connectors
• main resevoir

Question 2

where is the hydraulic access point?

Answer 2

aft of the main left landing gear

Question 3

what does the crossfeed valve allow?

Answer 3

one system to pressurise the other systems components

Question 4

what powers the hydraulic pumps?

Answer 4

ACW

Question 5

what is the pump delivery pressure?

Answer 5

3000psi

Question 6

what powers the blue pump?

Answer 6

ACW BUS 1

Question 7

what powers the green pump?

Answer 7

ACW BUS 2

Question 8

What is the purpose of the Auxiliary DC hydraulic pump?

Answer 8

pressurises the blue system components when the aircraft is on the ground with no power

Question 9

can we crossfeed when the auxiliary pump is being used?

Answer 9

no

Question 10

what output does the aux pump produce?

Answer 10

1/3 of the main pump pressure

Question 11

at what system pressure will the auxiliary fuel pump start running?

Answer 11

when blue system pressure drops below 1500psi

Question 12

what is required for automatic operation of the aux hydraulic pump?

Answer 12

• gear handle down
• release prop brake
• one engine running

Question 13

what does the blue hydraulic system supply?

Answer 13

• NWS
• Flaps
• spoilers
• prop brake
• parking brake
• emergency brake

Question 14

what does the green hydraulic system supply?

Answer 14

• LDG gear
• normal brakes

Question 15

what is the total capacity of the hydraulic tank?

Answer 15

9.6L

Question 16

what is the refill line on the hydraulic sight glass signifying?

Answer 16

8.5l

Question 17

what is the normal fill level on the hydraulic resevoir?

Answer 17

9.35l

Question 18

what are the 2 approved hydraulic fluids?

Answer 18

• skydrol ld4
• HYJET IV

Question 19

what is the capacity of the blue and green hydraulic fluid compartments?

Answer 19

4 litres

Question 20

when will we get a LO LVL on the hydraulic power panel and EWD?

Answer 20

below 2.5L

crossfeed also automatically closes

Question 21

what are the indicators for a clog?

Answer 21

turkey poppers on the aft side of the resevoir

Question 22

what displays when the green pressure drops below 1500psi?

Answer 22

single chime

caution

HYD GREEN LO PR

LO PR on green pump button

Green systems on ACW hydraulic page go amber

Question 23

when will an overheat condition of the green system occur?

Answer 23

temperature sensed by the green pump return line sensor exceeds 121 degrees

Question 24

what should we do if an OVHT is sensed?

Answer 24

turn off the pump, open the crossfeed and wait for the system to cool down

Question 25

what does the check valve downstream of the hydraulic pump do?

Answer 25

prevents back flow of the opposite systems hydraulic fluid if crossfeed is being used

Question 26

what the green accumulator do?

Answer 26

shock absorber against pressure surges and assists the hydraulic pump when there is high demand

Question 27

what is in the accumulator?

Answer 27

0.2L of nitrogen

Question 28

where is the pressure sensor for indication in the green system?

Answer 28

downstream of the check valve

Question 29

what is the corrective action for a low pressure on either system?

Answer 29

switch off the affected pump and turn on the crossfeed

Question 30

what can be set once we re energise the blue system using the auxiliary pump?

Answer 30

park brake can be set prop brake can be engaged

Question 31

what is the blue aux pump powered by?

Answer 31

HOT MAIN BAT BUS DC BUS 2

Question 32

HOW LONG WILL THE AUX PUMP RUN FOR when the button is pressed?

Answer 32

30 seconds

Question 33

when will the aux blue pump run when one engine is running?

Answer 33

gear handle down aux pump push button on panel depressed blue output pressure below 1500psi prop brake not engaged

Question 34

how long will the aux pump operate for if the prop brake is engaged?

Answer 34

for 15 seconds after brake engagement

Question 35

if the aux pump was triggered by a main pressure drop of below 1500psi, when will it stop running?

Answer 35

when main pressure reaches 2100 psi

Question 36

when will LO PR show on aux pump button with associated chime and EWD?

Answer 36

OUTPUT PRESSURE BELOW 1500 PSI

Question 37

What do the check valves in the blue sysem prevent?

Answer 37

backflow to the main pump line and aux pump line in event of crossfeed from green system

Question 38

when will the crossfeed valve automatically close?

Answer 38

when fluid level in either system drops below 2.5 litres

Question 39

what powers the crossfeed valve?

Answer 39

DC STBY BUS

Question 40

what happens if power is removed/lost from the crossfeed valve?

Answer 40

crossfeed valve automatically closes

Question 41

how many applications of the park brake is stored in the accumulator?

Answer 41

6

Question 42

where is park/emergency brake accumulator pressure displayed?

Answer 42

left maintenance panel and ACW/hydraulic page

Question 43

what are the hydraulic pump buttons/lights powered by?

Answer 43

Green button: DC ESS BUS Green lights: DC EMER BUS Blue buttons/lights: DC EMER BUS