Oral Bank - FUEL SYSTEM

Question 1

How is Center Wing Tank Fuel scavenged?

Answer 1

CWT fuel is scavenged by 4 jet pumps pumping into main tanks 2 and 3 (scavenge begins approx when main tank 2 or 3 quantity drops to 27,200kgs)

Question 2

Which cross feed valves are controlled by Fuel System Management logic when setting T/O flaps?

Answer 2

Crossfeed valves 2 and 3

Question 3

During the Before Start Procedure, at which centre wing tank quantity are you required to select the centre wing pumps on? Quantity in LBS for the LCF?

Answer 3

• 7,700kgs or more in the center wing tank.
• 17,000lbs or more in centre wing tank (LCF)

Question 4

Main Tanks 2 and 3 override/jettison pumps can operate to a standpipe level of approximately _______kgs (400), _______kgs (LCF), ________kgs (-8) of fuel remaining in each tank?

Answer 4

• 3,200kgs (400)
• 7,000lbs (LCF)
• 3,450kgs (-8)

Question 5

Describe how the fuel quantity indication changes upon termination of fuel jettison?

Answer 5

• Changes from magenta to white
• Fuel remain quantity flashes for 5 seconds

Question 6

How does the Centre Wing Tank Fuel scavenge in the LCF?

Answer 6

CWT electric pump into M2 tank when:
- CWT override/jettison pump has low pressure
- Fuel quantity in M2 OR M3 tank is below 40,200lbs)

Question 7

State what occurs when you select the fuel jettison switch to A or B? (2)

Answer 7

• Arms the jettison selector
• Displays preselect fuel to remain on EICAS

Question 8

What is the impact on the aircraft with excessive fuel imbalance? (3)

Answer 8

• Adversely affects CG
• Aerodynamic drag
• Fuel economy

Question 9

When do the FSMC’s open the reserve transfer valves on the 400, LCF, -8?

Answer 9

400: When main tank 2 or 3 fuel quantity decreases to approx. 18,200kgs
LCF: When main tank 2 or 3 fuel quantity decreases to approx. 40,200lbs
-8: When main tank 1 or 4 fuel quantity decreases to approx. 6,100kgs

Question 10

In which tank is fuel temperature measured?

Answer 10

Main tank 1

Question 11

In general, how would you handle an excessive fuel imbalance situation?

Answer 11

By opening or closing cross feed valves and turning off and on fuel pump switches (referring to QRH and Supplementary Procedures)

Question 12

Which fuel tanks do reserve tank 1 and 4 transfer to on the 747-8?

Answer 12

Main tanks 1 and 4

Question 13

On the 747-8, at what fuel quantity will the fuel jettison complete jettison operations with the selector in MLW position?

Answer 13

Maximum landing weight plus 3,000kgs

Question 14

During fuel jettison on the LCF, transfer valves open when fuel quantity in tanks 2 or 3 decrease to _________lbs?

Answer 14

20,000lbs