Fuel System

Question 1

SPR drain

Answer 1

28 VDC
2.5 minute cycle-pressing switch while in progress restarts the cycle
drains into Number 3 tank

Question 2

Fuel quantities

Answer 2

1-4=8310
2,3=7650
L/R aux=5810
L/R ext=8900
Fuse=24,392

Question 3

Tanks

Answer 3

all fuel tanks, except for the fuselage tank, are equipped with baffle systems fabricated from explosion-suppressant, conductive foam
water removal system: two ejectors, a check valve, a strainer, and associated plumbing in each main tank
fuel tank vent system: aux and inboard tanks have a wrap around vent system
fuel level control valves: spring closed, with AR pods, one in each tank, three in tanks 1,4
two pumps in each tank, except for AUX tanks

Question 4

Fuel pumps

Answer 4

boost pumps provide fuel directly to the engine through the firewall valve and transfer pumps provide fuel to the cross feed manifold

Question 5

Boost pumps

Answer 5

3 phase, 400 HZ, 115/200 VAC powered by the ECB
400 degrees F/204 degrees C thermal fuse, non-reset; located in each phase lead
6000 pph at 15-24 psi and are turned on by turning the start switch to run

Question 6

Transfer pumps

Answer 6

3-phase, 400 HZ, 115/200 VAC
28-40 psi and are turned on by pushing the “from” switch on the overhead or augmented crew station fuel control panel
the external tanks have 2 transfer pumps which alternate when used and both are on during dumping

Question 7

Low fuel state operations

Answer 7

• defined as operations that result in the aircraft landing at the final destination with less than 6,000 lbs of fuel.
• If anticipated, upon reaching 8,000 lbs total, level the main fuel tanks using transfer pumps
• open the cross-feed switches and the cross-ship manifold
• declare an emergency when you need to (NATOPS “3000 lbs”)

Question 8

Fuel system emergencies-External fuel leak

Answer 8

Land at the nearest airfield with sufficient runway to complete the landing roll without using reverse thrust. An emergency should be declared and fire fighting equipment requested due to possibility of fire
If a fuel leak develops in the wing flap area and a fuse tank is installed, the aircraft should be depressurized

Question 9

Fuel dump

Answer 9

All fuel except 1520 lbs in each main tank can be dumped, all fuel except 1008 lbs can be dumped from the fuse tank using the AR pumps, the remaining fuse tank fuel may be dumped using the transfer pumps–to dump the most fuel in the least time, transfer into fuse tank while dumping with AR pumps