Fuel System

Question 1

How many wing tanks?

Answer 1

4 wing tanks

Question 2

Capacity of all 4 wing tanks (non-ER)

Answer 2

180, 664 lbs JP-8

Question 3

how is fuel transferred within the inboard wing tanks (non-ER)?

Answer 3

automatically transferred from aft compartment to forward feed box by jet pump energized by boost pumps or transfer pump
SCHED light comes on if it occurs as scheduled

Question 4

how is fuel transferred within the outboard wing tanks (non-ER)?

Answer 4

fuel is transferred internally from inboard to outboard and then to the engine

Question 5

Capacity of all 4 wing tanks (w/ ER) plus 4 center wing box compartments?

Answer 5

245, 208 lbs JP-8

Question 6

how is fuel transferred within the ER tanks?

Answer 6

pumped to the inboard wing tanks then to the forward feed boxes until ER tanks are empty

Question 7

How is fuel transferred within the inboard and out board tanks for a w/ ER aircraft?

Answer 7

same as non-ER aircraft

Question 8

What does the fuel management system keep the outboard tanks full at?

Answer 8

~38,000 lbs until the inboard tanks reach the same level and then they burn down evenly

Question 9

fuel management flow of fuel

Answer 9

flows fuel outboard from tank #2 to #1 and tank #3 to #4 to maintain balance

Question 10

what is fuel scheduling?

Answer 10

the internal process within the tanks to move the fuel outboard (outboard tanks) or forward (inboard tanks) within the respective tanks

Question 11

What does the SCHD light on the fuel mgt button mean?

Answer 11

automatic management of fuel to maintain the outboard tanks full at 38,000 lbs has failed
or the inboard to outboard transfer fails to stop and outboard tanks quantity exceeds inboard tank quantity
don’t confuse it with an “inboard” tank SCHD light

Question 12

What does an inboard tank SCHD light mean?

Answer 12

fuel isn’t transferring from the aft inboards for the forward inboards

Question 13

inboard tank capacities?

Answer 13

~52K (84K with ER) JP-8

Question 14

outboard tank capacities?

Answer 14

~38K JP-8

Question 15

total fuel capacity?

Answer 15

~180K/245K with ER

Question 16

fuel capacity memory aids

Answer 16

T-38 (outboard w/o ER)
B-52 (inboard)
F-84 (total w/o ER)

Question 17

What happens when fuel drops to 16K lbs?

Answer 17

“LOW” light on Total Fuel Indicator and LOW FUEL appears on the WAP
LOW appears on the Total Fuel panel

Question 18

What happens if a tank reaches 4K lbs?

Answer 18

Fuel QTY X message appears on the WAP

Question 19

At what quantity to inboard tank XFER pumps become uncovered at?

Answer 19

28K/12K (inboards/outboards)

Question 20

At what quantity should fuel dumping automatically stop at?

Answer 20

20,000 lbs

Question 21

Dumping at altitudes above ___ could cause a flameout

Answer 21

20,000 ft

Question 22

How does the fuel feed between tanks?

Answer 22

“FAA”
Forward ER to forward inboard
Aft ER to forward inboard
Aft inboard to forward inboard

Question 23

FUEL QUANTITY X

Answer 23

appears on the WAP when fuel level is below 4000 lbs in the respective tank

Question 24

LOW fuel light on the Total Fuel Indicator (TFI)

Answer 24

total fuel quantity is less than 16,000 lbs

Question 25

L/R FUEL HEAVY

Answer 25

fuel difference between wings exceeds 8000 lbs and may require manual fuel transfer to solve the imbalance

Question 26

SCHD light (respective inboard tank)

Answer 26

fuel in the fwd compartment of inboard tank decreases to 25,000 lbs but there is still 1000 lbs in the aft compartment

Question 27

Fuel Management SCHD light

Answer 27

outboard tanks is less than 37,700 lbs and the adjacent inboard tank is more than 40,400 lbs
or
outboard tank is full and the adjacent inboard tank is less than 36,900 lbs