Fuel System

Question 1

Main fuel tank capacity

Answer 1

8,234 lbs/1,229 gallons

Question 2

Center Fuel Tank Capacity

Answer 2

27,932 lbs/4,169 gallons

Question 3

Forward Aux Tank Capacity

Answer 3

10,050 lbs/1,500 gallons

Question 4

Aft Aux Tank Capacity

Answer 4

16,589 lbs/2,476 gallons

Question 5

Total Aux Fuel Capacity

Answer 5

26,639 lbs/3,976 gallons

Question 6

Total Fuel Capacity without Aux Fuel

Answer 6

44,400 lbs/6,627 gallons

Question 7

Total Fuel Capacity with Aux Fuel

Answer 7

71,040 lbs/10,603 gallons

Question 8

Surge Tank Capacity

Answer 8

57 Gallons

Question 9

How many fuel pumps

Answer 9

2 AC pumps per tank (6 total)

Question 10

How is fuel used by center tank first?

Answer 10

Center pumps are more pressurized forcing use first

Question 11

How are the fuel pumps cooled and lubricated?

Answer 11

Fuel passing through

Question 12

How is aux fuel transfered?

Answer 12

1) OBIGGS
2) Right Environmental Control System PACK Water Separator
3) Differential Pressure

Question 13

When does Aux Fuel Transfer?

Answer 13

Center tank is less than 4,000 gallons (26,800 lbs)
10 minutes after airborne
10 minutes after AAR powered off

Question 14

Where does Aux Fuel Transfer?

Answer 14

Center tank

Question 15

When will aux fuel not transfer

Answer 15

If center tank is less than 400 lbs

Question 16

What happens to fuel pumps after tank is empty?

Answer 16

Auto shutoff to not burn the motor out

Question 17

What if the pumps fail?

Answer 17

Suction Feed

Question 18

Risk of Suction feed?

Answer 18

Flameout on climb. Dissolved air and light fuel constituents are released which can restrict fuel flow. Will deplete at cruise

Question 19

Scavenge Jet Pumps

Answer 19

Transfer fuel from center tank to left main tank. Must have No1 forward fuel pump on and tank must be 1/2 full

Question 20

Fuel Cross Feed power

Answer 20

DC Power on Battery Bus

Question 21

How does cross feed work?

Answer 21

Turn off pump you dont want feeding. Will lead to imbalance if forgotten about

Question 22

What are the types of shutoff valves?

Answer 22

Spar Valve and Engine Fuel Shutoff Valve

Question 23

Spar Valve Location

Answer 23

Engine mounting wing station

Question 24

Spar Valve Power

Answer 24

DC Power on Hot Battery Bus

Question 25

Engine Fuel Shutoff Valve Power

Answer 25

DC Power on Battery Bus

Question 26

Engine Fuel Shutoff Valve Actuation

Answer 26

Fuel Actuated and Solenoid Controlled

Question 27

When do the shutoff valves close?

Answer 27

Engine Fire Switch pull or Engine Start Level to Cutoff

Question 28

Where are the fuel temperature sensors?

Answer 28

Center - Override Pump Inlets Main - Feed Bay

Question 29

What is displayed in the temperature selector when fuel is below ___ lbs?

Answer 29

--- is displayed below 700 lbs

Question 30

When are the overtemperature alerts activated?

Answer 30

57 degrees for feeding and 60 degrees for non feeding

Question 31

What happens if overheat test is held?

Answer 31

If held for 15 seconds, assumes the switch is stuck and deactivates the test

Question 32

Configuration of Aux fuel?

Answer 32

3 forward 4 aft or 1 forward 4 aft

Question 33

How is aux fuel connected to main tank?

Answer 33

Vent Transfer line Interconnect

Question 34

Sensors for over pressurization from NEA, fuel expansion or overflow?

Answer 34

Pressure switch, 2 pressure transducers, mechanical pressure relief valve

Question 35

When is the NEA shutoff valve closed?

Answer 35

Air source temperature exceeded

Question 36

When will the NEA shutoff valve reopen after being closed?

Answer 36

Temperature switch is reset Aux Fuel pressure transducer indicates need for pressure Controller times out

Question 37

What is fuel quantity indication system used for

Answer 37

Aerial Refuel Ground Refuel Aux Tank Fuel Transfer Fuel Tank Temperature Indication Fuel Tank Low or High Temp

Question 38

Accuracy of FQIS?

Answer 38

1%

Question 39

FQIS Alerts

Answer 39

Low - Less than 2,000 lbs remaining in main tank Config - Engines running w more than 1,600 lbs of fuel in center tank with pumps off Imbal - 1,000 fuel difference

Question 40

Fuel Flow Sequence

Answer 40

Aux Tank Vent/Transfer Line Interconnect to center tanks AC Powered Fuel Pumps (suction feed line if low pressure in main tank)(Jet transfer pump to main tank if center tank is off and forward main tank 1 pump on with 1/2 fuel gone) Spar Shutoff Valve First Stage Fuel Pump IDG cooler (Part Returned, part continued) Main engine oil cooler Fuel Filter Second Stage Fuel Pump Hydromechanical Unit Engine Shutoff Valve Fuel Flow Transmitter Combuster

Question 41

What does the hydromechanical unit do?

Answer 41

Meters fuel through from the EEC based on the difference in commanded N1 versus actual N1

Question 42

Prohibited Fuels

Answer 42

JP-4 and Jet B

Question 43

Fuel Types

Answer 43

JP-5, JP-8, F-24, A1, A

Question 44

Emergency Fuel Types

Answer 44

JP-8+100, F-27

Question 45

IDG Fuel Cooling Flow

Answer 45

Pressure return line Gen Cooling Valve Fuel Mixing Injector Pump In Tank Distribution Manifold Fuel Transfer line with center tank feeding

Question 46

What controls Gen cooling valve from the IDG fuel cooling?

Answer 46

Engine Fire Switch and Fuel Control Switch Automated Manual from Gen1/2 Cooling switches to minimize the return to tank flow

Question 47

3710 Fuel Planning Requirements

Answer 47

TO to Destination (Initial approach if using alternate then to alternate) + 10% No less than 20 minutes at 10,000' at max endurance