Fuel

Question 1

The fuel tank system is comprised of?

Answer 1

• Center tank (174,900 lbs).
• 2 main tanks (64,100 lbs).
• 2 surge tanks

Question 2

How many fuel pump do the left and right main fuel tanks have?

Answer 2

Each contain two AC-powered fuel pumps.

Question 3

How many fuel pumps are in the center tank?

Answer 3

The center tank contains two AC-powered override/jettison pumps.

Question 4

How is fuel fed to the APU?

Answer 4

A DC fuel pump, located in the left main tank, feeds fuel to the APU until AC power is established.

Question 5

How is fuel quantity measured?

Answer 5

By sensors in each tank and monitored by a Fuel Quantity Indicating System (FQIS).

Question 6

What conditions cause the expanded fuel quantity to display on the EICAS?

Answer 6

• One or both crossfeed valves are open
• One or more fuel tank quantity indications are inoperative
• FUEL IN CENTER alert message is displayed (center tank quantity is amber)
• FUEL QTY LOW alert message is displayed (low main tank quantity is amber)
• FUEL IMBALANCE alert message is displayed
• Airplane is on the ground with one or both engines off