Fuel Flashcards
What is the maximum permissible fuel imbalance for ground operations, and during takeoff and landing? (AFM Limitations)
600lb (266kg)
What is the maximum permissible fuel imbalance during flight? (AFM Limitations)
1,100lb (488kg)
At what level of fuel imbalance in flight will the auto transfer system activate?
340lb on the ground
510lb in flight when the total fuel volume is over 16,000lb
What is the maximum useable fuel load during pressure refueling? (AFM Limitations)
Wings: 17,550lb each
Center: 14,200lb
Aft: 2,550lb
Total: 51,850lb
What are the limitations when using wide cut fuels? (AFM Limitations)
They are prohibited
What is the minimum fuel quantity for manual wing-to-wing fuel transfer? (AFM Limitations)
2,500lb per wing tank
When must the fuel cross-feed system be selected OFF? (AFM Limitations)
Takeoff and Landing
For normal operations (both engines operating), must be selected OFF below 10,000ft
Which fuel tanks cannot be gravity refueled?
Center and aft
How is positive fuel tank pressure maintained during flight?
Ram air via NACA scoops on the bottom of each surge tank located at the wing tips
To avoid fuel spillage, at what fuel quantity should the pressure relief valve (PRV) handles not be pulled?
Wing tank quantity more than 11,300lb or the center tank is more than 12,000lb
Note: There is a placard on the aircraft adjacent to the valve.
What does the amber FUEL QTY MISCOMPARE CAS message indicate?
Mis-compare between the FMS calculated fuel and the sensed fuel on board
Note: This is probably a leak. The checklist will direct you to the “Fuel Leak In-Flight” checklist.
When does FRTT (fuel-return-to-tank) automatically operate?
Above 30,000ft feet and
Wing fuel temperatures colder than -20ºC
Note: Automatically closed when any fuel tank temp sensor is -5ºC or higher, or when the altitude is below 30,000ft.
When do the primary AC fuel pumps operate in flight?
ENGINE RUN switches to ON
XFEED SOV is selected open
Note: This is most noticeable during single engine operations, however is not a normal procedure during single engine operations.
When do the auxiliary DC fuel pumps automatically operate?
When low pressure is sensed at the AC fuel pump outlet
Note: May be caused by an AC pump failure, loss of power to the primary pump, or deselection of the primary pump.
Where is the fuel SOV located, and how is the valve closed?
Located in the engine feed line at the firewall
Closed by pressing the associated engine FIRE PBA
When does fuel transfer from the center tank to the wing inner tanks begin?
When inner wing tank quantities decrease to about 14,000lb
Continues until wing inner tanks reach full capacity (approximately 15,000lb)
When does fuel transfer from the aft tank to the wing inner tanks begin?
When either wing inner tank quantity decreases to 6,800lb
When will the wing outer tanks deplete into the wing inner tanks?
When wing inner tanks decrease to about 10,850lb
Which wing tank normally provides fuel for the APU?
Right wing collector tank
When is longitudinal CG control inhibited?
Pressing the CG CTRL PBA
When wing-to-wing transfer is automatically or manually initiated
When the fuel quantity of each wing inner tank reaches 10,850lb
Why must the crew monitor manual operation of the wing-to-wing transfer system?
No automatic shutdown of the manual system or overfill protection provided to stop operation
What powers the Refuel/Defuel panel?
MAIN BATT BUS
Note: This makes it possible to refuel without external or airplane-generated power
During the refuel SOV test, what does display of the “SOV FAIL” message in the PRESEL window indicate?
Fuel flow will not stop when the tank is full
