Fuel

Question 1

How many pumps are in each tank.

Answer 1

2 AC driven pumps in each tank (6 total)

Question 2

What does FUEL LOW mean

Answer 2

Fuel quantity is less than 2,000 in either main tank

Question 3

What does FUEL CONFIG mean

Answer 3

• Center tank has more than 1,600lbs
• Both center tank pumps are producing low/no pressure
• Either engine is running

Question 4

What does INSUFFICIENT FUEL message mean

Answer 4

The FMC calculates your landing fuel weight will be less than 2,000lbs

Question 5

How are the ENGINE VALVE and SPAR VALVES operated?

Answer 5

Via the engine start levers.

Question 6

How are the ENGINE VALVE and SPAR VALVE manually overridden?

Answer 6

By pulling the Engine Fire Switch

Question 7

What happens if BOTH main tank AC pumps are displaying LOW PRESSURE lights?

Answer 7

The engine will continue to operate via suction feed fuel supply

Question 8

At what altitude is suction feed not safe

Answer 8

Above 30,000ft flameout and thrust degredation can occur

Question 9

With all pumps ON and fuel in all tanks, how does the airplane draw from the center tank and not the wing tanks?

Answer 9

Output pressure on the center tank pumps is higher than the wing tank pumps.

Question 10

How is the XFEED valve operated

Answer 10

DC powered from Battery bus

Question 11

How does the APU get its fuel supply

Answer 11

Either AC driven pumps in tank 1
Suction feed from Tank 1
Tank 2 with XFEED VALVE open

Question 12

At the gate, where should the APU receive fuel

Answer 12

+1,000lbs in Center Tank: CENTER
-1,000lbs in Center Tank: Left

Question 13

What is the purpose of the scavenger pump?

Answer 13

To get fuel that in inaccessible to the Center tank AC pumps into a useable area (tank 1)

Question 14

How does the scavenger pump operate?

Answer 14

Via notice flow from the L FWD AC pump

Question 15

When is the scavenge pump operable

Answer 15

When L tank fuel is less than half