Section 05 - Fuel

Question 1

What might cause the illumination of a red “FUEL PRESS LOW” CAS message?

Answer 1

1. Both fuel boost pumps for that engine switched OFF with the cross flow closed
2. fuel pressure at the inlet side of the high pressure fuel pump less than 15 PSI
3. Fuel leak

Question 2

How is a fuel imbalance corrected using the cross flow valve?

Answer 2

By opening the cross flow valve and turning off the fuel pumps on the light wing

Question 3

What are the correct indications during the fuel quantity indicator test?

Answer 3

L - 7,000 R - 7,000 Total - 14,000

Amber L-R FUEL LEVEL LOW CAS message

Question 4

Where is the fuel hopper located?

Answer 4

In the inboard portion of each wing tank

Question 5

Fuel low-level warning is provided by low-level sensors, which are installed where in the wing?

Answer 5

In the fuel hopper tank

Question 6

Where are the electric fuel boost pumps located?

Answer 6

In the main wheel well

Question 7

What is the function of the pressure fueling static port located under each wing?

Answer 7

It provides a reference pressure to prevent over-pressurization of the wing during fueling operations

Question 8

How are the main fuel shutoff valves checked during the preflight walk-around?

Answer 8

Verify that the valves are open by physically checking that the red valve position indicator is in approximately the seven o’clock position

Question 9

When and how is a fuel quantity update performed?

Answer 9

Hourly, using data from the FQMS. On FMS PERF INIT page 5/5, perform a “DELETE” to line select key 2L

Question 10

What are the electrical power sources of the fuel boost pump?

Answer 10

L & R MAIN: ESS DC bus

L & R ALT: R MAIN DC

Question 11

How much fuel is remaining in the hopper when an amber left or right “FUEL LEVEL LOW” CAS message appears?

Answer 11

Approximately 650 lbs

Question 12

What is the capacity of each fuel hopper tank?

Answer 12

190 gallons

Question 13

What is the maximum standard fuel load?

Answer 13

29,500 lbs, more can be added provided max ramp and max takeoff weights are not exceeded, and the loaded airplane center of gravity is within limits

Question 14

What is the maximum fuel imbalance?

Answer 14

Varies with aircraft weight, reference chart in QRH, Section EF

Question 15

If a main fuel boost pump should fail, will the alternate fuel boost pump automatically turn on, if selected OFF?

Answer 15

Yes, there is a boost pump auto-change feature.

Question 16

If you are powering the aircraft with the HMG only, what components of the fuel system will be available?

Answer 16

L & R MAIN BOOST pumps

Crossflow & Intertank Valve

Question 17

If an engine fire handle is pulled, where is the fuel shut off?

Answer 17

At the boost pumps in the main wheel well

Question 18

The engine should run without boost pump pressure up to what maximum altitude?

Answer 18

20,000ft

Question 19

If two boost pumps fail on the same side, how would you keep the fuel balanced?

Answer 19

By opening the intertank valve and using sideslip (nose of the aircraft toward the heavy wing)

Question 20

How are the hopper tanks kept full?

Answer 20

Flapper valves and ejector pumps

Question 21

Where can fuel quantity indications be read?

Answer 21

1. On DU #3, engine instruments display
2. Standby fuel quantity indicator
3. On the FUEL synoptic page

Question 22

What is the difference between “fuel temperature” and “engine fuel temperature“?

Answer 22

Fuel temperature (found on the FUEL synoptic page) is the temperature of the fuel in the left hopper. Engine fuel temperature is the temperature of the fuel as it exits the engine oil cooler.

Question 23

What does the “CB” light in each boost pump control switch indicate?

Answer 23

The respective circuit breaker on the PDB is tripped.

Question 24

What is the maximum fuel imbalance at 55,000 lbs airplane gross weight?

Answer 24

2,000lbs

Question 25

What is the maximum fuel imbalance at 61,000 lbs airplane gross weight?

Answer 25

400 lbs

Question 26

What is the maximum engine fuel temperature?

Answer 26

90ºC (fuel temperature up to 120ºC for a maximum of 15 minutes is permissible)

Question 27

What is the minimum engine fuel temperature?

Answer 27

-40ºC