12 Fuel

Question 1

Maximum permissable fuel imbalance between the contents of the main left tank and the main right tank for approach, take-off and taxi?

Answer 1

400 lbs (182 kg)

Question 2

Maximum permissable fuel imbalance between the contents of the main left tank and the main right tank in flight?

Answer 2

800 lbs (363 kg)

Question 3

Fuel tank capacity
* L and R main tank
* Auxiliary tank
* Tail tank
* Total

Answer 3

• 4,860 lbs (each)
• 7,168 lbs
• 3,112 lbs
• 20,000 lbs

Question 4

How much fuel with gravity refueling?

Answer 4

15,722 lb
No fuel in tail tank and 7% less in the remaining tanks.

Question 5

How is the fuel transfered through the different tanks?

Answer 5

The tail tank fuel is transferred to the AUX by electrically operated tail transfer pumps. The auxiliary tanks feed fuel to the main wing tanks using transfer ejector pumps. The main tanks supply fuel to their respective engines via two collector tanks using gravity or scavenge ejector pumps or electric boost pumps.

Question 6

What is the left/right boost pumps powered by?

Answer 6

Left: DC battery bus
Right: DC bus 2

Question 7

When does the boost pump activate?

Answer 7

If a single BOOST PUMP is armed, both will activate if low pressure is sensed on the armed side.

Question 8

The two tail tank transfer pumps transfer fuel at a constant rate of?

Answer 8

1,800 pounds pr. hour

Question 9

What happens if a rotor burst happens?

Answer 9

The tail tank lines run past the engines and are pressurized with nitrogen, should a burst happen, pressure will be lost and the transfer will be inhibited. Message “AUTO TAIL XFER INHIB”. It is usable with maunal override.

Question 10

In what order is fuel used?

Answer 10

1. Wings down to 93%
2. Tail to 38%
3. Aux to 35%
4. Tail to 0%
5. Aux to 0%
6. Wings to 0%

Question 11

What conditions must be in order prior to fuel dumping, and what rate can you expect?

Answer 11

• Not near lightning
• Flaps 0
• 100-120 lb/min

Question 12

“BULK FUEL TEMP” caution.

Bulk fuel temperature is monitored by a probe in the left main tank, what temperature causes the associated “BULK FUEL TEMP” caution?

Answer 12

At or below -37 degrees C

Question 13

“L/R FUEL LO TEMP” caution.

Engine fuel is sensed by a probe located on the top of each engines fuel filter, and what temperature does the caution message “L/R FUEL LO TEMP” trigger?

Answer 13

Below + 5 degrees C

Question 14

From what tank does the APU use fuel?

Answer 14

R main tank (R wing)

Question 15

EICAS low fuel caution

Answer 15

Mains below 500 lbs
Total below 1000 lbs