Fuel

Question 1

How many fuel tanks does the 737 have?

Answer 1

3 ( 2 main tanks (1 in each wing) and a centre tank)

Question 2

How are fuel pumps cooled and lubricated?

Answer 2

By the fuel passing through the pump

Question 3

Output of the centre tank fuel pumps

Answer 3

23 psi

(higher than the main tanks so that centre tank is emptied first)

Question 4

Main tank pump output

Answer 4

10psi

Question 5

What happens to the centre tank fuel if the AC transfer buses loose power?

Answer 5

The remaining fuel cannot be retrieved

Question 6

Where is the check valve in the main tank to prevent outboard fuel flow in the wings?

Answer 6

Wing rib 8

Question 7

Centre tank pump low pressure warning illuminates when?

Answer 7

When output pressure is less than 22psi (after a 10 second delay)

Question 8

Where is fuel temperature indication taken from?

Answer 8

Fuel tank #1

Question 9

Maximum and minimum fuel temperatures

Answer 9

Maximum: 49 degrees Celsius
Minimum: -43 degrees Celsius or 3 degrees above fuel freezing point (whatever is higher)

Question 10

What type of motor is the fuel cross feed and what is it powered by?

Answer 10

DC motor powered by the BAT Bus

Question 11

Main fuel pump low pressure warning light illuminates when?

Answer 11

Less than 4psi output

Question 12

What does the fuel quantity indicating system (FQIS) consist of?

Answer 12

Consists of 32 tank units, 3 densitometers and 3 compensators.

Question 13

What is the fuel quantity processor unit (FQPU)?

Answer 13

Calculates fuel weight and supplies data to FMCS, CDS and refuel panel

Question 14

Maximum fuel quantity calculation error in the FQIS?

Answer 14

2.5%

Question 15

Why would the fuel quantity blink on the refuel panel?

Answer 15

The tank is overfilled

Question 16

FUEL LOW warning

Answer 16

Depending on version:

Less than 907kg or 453kg in main tank

907kg: remains illuminated until 1134kg
453kg: remains illuminated until 567kg

Question 17

When will the FUEL CONFIG warning illuminate?

Answer 17

-Either engine is running
-(Certain models) Both centre tank low press or both centre tank pumps are off
-Centre tank has more thank 726kg and is shown until quantity decreases below 363kg

Question 18

What causes the FUEL IMBAL warning to illuminate?

Answer 18

Fuel in main tanks differ by more than 453kg, extinguishes when difference is reduced to 91kg.

Question 19

How much does the nitrogen generating system decrease oxygen levels?

Answer 19

Decreases oxygen in the centre tank by 12%

Question 20

Where does the nitrogen generating system get its air from?

Answer 20

LH side bleed air

Question 21

Where is the refuel panel located?

Answer 21

Leading edge of the right wing

Question 22

How is the refuelling panel energised?

Answer 22

-External power
-Any AC power source
-Battery power (with battery switch on)