Fuel

Question 1

At what fuel quantity is operation of

the pressure relief valves prohibited

Answer 1

Wings >11,800 lbs or

Center >8,000

Question 2

What does
“COMPARE FUEL QUANT”
Indicate

Answer 2

Dif. between FMQGC + FMS
fuel quantity reading greater than
2% of BOW ( aprox. 1020 lbs )

Question 3

When does FRTT
( fuel return to tank )
automatically operate

Answer 3

Above 34,000’

Any individual fuel temp sensor
Below -20 C

or average of all temp sensors
below -9 C

Question 4

When do AC wing boost pumps

operate

Answer 4

ENGINE RUN switch on

AC power available

XFEED valve open

note:
2 pumps per wing. Each pump capable
of providing 900 - 6500 lbs/hr
depending on freq. of VFG

Question 5

Where is the fuel SOV located

and how is it closed

Answer 5

Located behind the aft pressure bulkhead
Installed in the engine feed line

Closed via the associated
Fire discharge handle

Question 6

When does fuel transfer from center

tank take place

Answer 6

Wing tank quantity below 93%

Continues until wing reaches 97%

Question 7

When does fuel transfer from aft

tank start

Answer 7

Either wing tank below 5,500 lbs

Continues until <100 lbs in aft tank

Question 8

What happens when XFEED SOV

is selected

Answer 8

All 4 AC boost pumps will opperate
regardless of ENG. RUN switch
position

Question 9

When does wing DC aux pump

operate automatically

Answer 9

Low pres. of one or both AC pumps

AC pump failure

Flaps greater than 0

In flight, gear down and locked

Less than 600 lbs either wing

During auto wing transfer
( imbalance >400 )

Question 10

When will the AC boost pumps operate

regardless of ENG. RUN switch pos.

Answer 10

XFEED SOV open

Question 11

which tank normally provides fuel for APU

Answer 11

Right tank

note:
requires the operation of either
the right AC pumps or right DC pump

Question 12

Which pumps operate autonomously

Answer 12

Center tank transfer pumps

Question 13

How is fuel moved from fwd aux

tank to center tank

Answer 13

ejector pumps receiving motive flow
from center to wing transfer and / or
gravity flow at slower rate

Question 14

When does wing transfer automatically

initiate

Answer 14

Lateral imbalance 400 lbs or more

note:
SOV opens and heavy side DC pump starts

Question 15

When is wing transfer inhibited

Answer 15

Flaps greater than 0

In flight, gear down and locked

Low fuel. <600 either wing

DC aux pump supplying fuel feed
to an engine ( AC pump failure )

Question 16

refuel SOV test displays

SOV FAIL what does this indicate

Answer 16

Fuel flow will not stop when tank is full