Fuel

Question 1

Fuel

How many tanks are there ?

Answer 1

5
• 1 Center (68 T)
• 2 Main in each wing (2 x 16 T)
• 2 surge tanks in each wing

Question 2

Fuel

What is the Fuel capacity ?

Answer 2

About 101 T

Question 3

Fuel

What are the Surge tanks used for ?

Answer 3

• Fuel expansion

* Venting

Question 4

Fuel

Which Fuel pumps have the highest output pressure
• Main tank pumps or
• Center tank pumps ?

Answer 4

The CENTER tank pumps have a higher output pressure than the L and R main tank fuel pumps to ensure center tank fuel is used before main tanks fuel.

Question 5

Fuel

Can the fuel balancing system be used on the ground with engines shutdown ?

Answer 5

YES, if the APU is running.

Question 6

Fuel

In which phases of flight can the fuel balance system be used ?

Answer 6

All of them.

Question 7

Fuel

Can Fuel jettison nozzles be opened on the ground ?

Answer 7

NO

Question 8

Fuel

What system provides flammability protection for the fuel system ?

Answer 8

The Nitrogen Generation System (NGS).

Question 9

Fuel

At which rate is fuel jettisoned ?

Answer 9

• With fuel in Center tank ➝ 1.6 T/min

* Without fuel in Center tank ➝ 0.8 T/min

Question 10

Fuel

What system allows each engine to draw fuel from its respective Main tank if the pump pressure is low ?

Answer 10

Suction feed that bypasses the pumps.
During climb or at high altitude, the engine may not run properly or have a flame out. This is due to diluted air being released from the fuel as pressure decreases.

Question 11

Fuel

Where is the Jettison time shown ?

Answer 11

On the FUEL synoptic.

Question 12

Fuel

When is fuel balancing inhibited ?

Answer 12

Any of the following reasons:

• Refueling control panel is used,
• Prior to engine start and the APU is off,
• Fuel balance system is failed,
• A center tank pump is ON,
• On the ground and one or both engines are running,
• In flight and the fuel jettison system is active,
• In flight and FUEL DISAGREE is displayed,
• In flight and the FUEL QTY LOW is displayed,

Question 12

a. How many fuel tanks does the aircraft have?b. Howaretheydesignated?

Answer 12

a. Threeb. Center, left and right main tanks

Question 13

Where are the fuel quantities displayed?

Answer 13

Primary EICAS display and FUEL synoptic

Question 14

During normal operation where can individual tank quantity be displayed?

Answer 14

On the FUEL synoptic

Question 15

Where is the fuel temperature displayed?

Answer 15

Primary EICAS display and FUEL synoptic

Question 16

Where do you enter the fuel freeze temperature?

Answer 16

The FMC CDU

Question 17

List the circumstances that cause the expanded fuel indications to appear on EICAS?

Answer 17

• The crossfeed valve open• One or more fuel tank quantity indications are inoperative• The FUEL IN CENTER alert message is displayed• The FUEL QTY LOW alert message is displayed• The FUEL LOW CENTER alert message is displayed• The FUEL FLOW ENG alert message is displayed• The INSUFFICIENT FUEL alert message is displayed• The FUEL IMBALANCE alert message is displayed• The airplane is on the ground and both engine(s) off• The balance system is active• The balance system is selected on and fuel is already balanced

Question 18

What indicates the low tank on the expanded EICAS during a fuel tank quantity imbalance?

Answer 18

A solid white fuel imbalance pointer is displayed if:• The FUEL IMBALANCE message is not displayed and the main tank fuel differs by more than 100 kilograms, and• Either the crossfeed valve is open or the balance system is ON

Question 19

What is indicated by the fuel imbalance pointer flashing?

Answer 19

The pointer flashes if fuel balance or crossfeed is going in the wrong direction

Question 20

What indications on EICAS are displayed as tank imbalance falls below 100 Kgs?

Answer 20

The FUEL BALANCED replaces FUEL QTY and flashes for 5 seconds

Question 21

What will happen as actual fuel temperature approaches preset fuel freeze temperature?

Answer 21

The fuel temperature on the EICAS display turns amber along with a “-“ indication

Question 22

What condition generates an EICAS FUEL DISAGREE advisory message?

Answer 22

The totalizer fuel quantity and the FMC calculated fuel quantity disagree

Question 23

a. How is the CALCULATED fuel quantity obtained? b. Which system provides the “TOTALIZER” value?

Answer 23

a. Quantity at engine start minus fuel used b. The totalizer fuel quantity system

Question 24

a. How many AC fuel pumps does each tank have?b. Do the centre pumps produce the same pressure as main tank pumps?c. With all tanks full and pumps operating, which tank supplies the engines?

Answer 24

a. Two AC–powered fuel pumpsb. No, they have a higher output pressurec. Center

Question 25

a. In which tank is the DC fuel pumpb. When does it operate?c. What will cause automatic shut down of the DC fuel pump?

Answer 25

a. The Left main tankb. When AC power is not available and the APU selector is ONc. When AC power available

Question 26

How does the fuel system respond if electrical power sources are limited?

Answer 26

Certain fuel pumps may be load shed until enough electrical power is available

Question 27

If a main tank fuel pump fails:a. Will selecting the pump switch off remove the message and light?b. Is the engine or aircraft operation affected with a tank pump OFF?

Answer 27

a. Nob. No, a single pump can supply sufficient fuel to operate one engine under all conditions

Question 28

With the Centre tank empty, if both left main tank pumps fail, how is the engine affected?

Answer 28

The engine can draw fuel from its main tank through a suction feed line that bypasses the pumps

Question 29

In flight, if the Centre tank empties, and both centre pump low PRESS lights are illuminated, what will happen to the lights (and associated EICAS messages) when the pumps are switched OFF?

Answer 29

The lights and the messages are inhibited

Question 30

What is the normal selection of the crossfeed switch?

Answer 30

Off, the crossfeed valve is closed during normal operations

Question 31

What is indicated if a crossfeed switch VALVE light remained illuminated after selection?

Answer 31

The crossfeed valve is not in the selected position

Question 32

The Fuel Balance System enables fuel to be transferred between which tanks?

Answer 32

The main tanks

Question 33

Does the Fuel Balance System operate with the centre tank pumps on?

Answer 33

No

Question 34

From which tanks can fuel be jettisoned?

Answer 34

All tanks

Question 35

What is the first action to jettison fuel?

Answer 35

Pushing the FUEL JETTISON ARM switch to select ARMED

Question 36

To what quantity will fuel be automatically jettisoned?

Answer 36

Fuel quantity TO REMAIN is set to maximum landing weight (MLW) automatically

Question 37

Where can jettison time be observed?

Answer 37

Jettison time is displayed in minutes on the fuel synoptic

Question 38

Can the jettison nozzles be opened on the ground?

Answer 38

No

Question 39

Can all the main and centre tank fuel be jettisoned?

Answer 39

No, main tanks will reduce to 3,900Kgs per tank, centre tank will empty

Question 40

a. How can the fuel TO REMAIN be selected manually?b. How will the EICAS fuel quantity display change following a manual selection?c. How can MLW be reset following a manual selection?

Answer 40

a. Pull on and rotate the TO REMAIN selector to manually decrease or increase the TO REMAIN quantityb. MAN replaces MLWc. Push in the FUEL TO REMAIN selector