Fuel System

Question 1

From which Fuel Tank can the APU receive fuel?

Answer 1

• Fuel is drawn from the Left Wing Fuel Hopper using the Left Main and/or Left Alternate Fuel Pumps
• Fuel can be drawn through the Crossflow Valve using the Right Main and/or Right Alternate Fuel Pumps

Question 2

Total fuel capacity

Answer 2

29,500LBS or 4,370GALS

Question 3

Fuel Tank Temperature Min

Answer 3

-40 C

Question 4

Fuel Tank Temperature Max

Answer 4

54 C and above

Question 5

Maximum Fuel unbalance

Answer 5

2,000LBS @ 55,000 gross wt

400LBS @ 60,500 gross wt

Question 6

3. What is the maximum capacity of each fuel hopper tank?

Answer 6

190 gallons (Approximately 1270 lbs)

Question 7

4. When a fire handle is pulled, where is the fuel shut off?

Answer 7

At the tank (engine fuel feed shutoff valve)

Question 8

5. How is pressure fueling terminated from the flight deck?

Answer 8

By selecting the left and right remote fueling shutoff switches to CLOSED

Question 9

6. Where is the amber “FUEL LEVEL LOW” indication displayed?

Answer 9

On the CAS

Standby fuel quantity indicator will display “LOW FUEL”

Question 10

7. What is boost pump auto change?

Answer 10

If one pump on either side is selected “OFF” and the operating pump fails, the
Selected Off Pump will automatically turn on
The corrective action is to match the switches to the condition

Question 11

8. What malfunctions or actions might cause a red “FUEL PRESS LOW” CAS
   message to illuminate?

Answer 11

If the fuel pressure at the engine driven high pressure fuel pump inlet is less than
15 psi
A fuel leak in the engine fuel system
Both fuel boost pumps on one side turned OFF with the crossflow valve CLOSED

Question 12

9. What is the corrective action required if a red “FUEL FILTER” CAS message
   illuminates?

Answer 12

Reduce power to 75% HP RPM on the affected engine and check for engine fuel
temperature increase above +5º C

Question 13

10. How is the fuel system configured with a dual converter failure?

Answer 13

One main boost pump selected ON with the crossflow valve OPEN

Question 14

11. What is the function of the pressure fueling static port underneath each wing?

Answer 14

To provide a static pressure reference for the tank pressure sensing valve in the
pressure fueling system

Question 15

12. What is the function of the remote fueling shutoff switches?

Answer 15

To control pressure fueling shutoff operation from the cockpit

Question 16

13. What are the normal indications on the fuel gauges with the standby fuel
    quantity gauge selected to “TEST”?

Answer 16

An amber 7000 lbs indication on each fuel gauge with the total fuel gauges
reading an amber 14,000 lbs indication and flashing “LOW FUEL” message for
approximately 30 seconds on the standby panel and “FUEL LEVEL LOW” on the
CAS

Question 17

14. What is an acceptable source of fuel for the APU?

Answer 17

Either the left main or left alternate boost pump selected ON
Either the right main or right alternate boost pump selected ON with the crossflow
valve OPEN

Question 18

15. If both fuel boost pumps on one side were selected to OFF after engine start,
    what would be the resulting indication?

Answer 18

A red “FUEL PRESS LOW” CAS message

Question 19

16. What is the function of the crossflow valve?

Answer 19

To supply fuel to both engines from one fuel tank, or to transfer fuel under
pressure to an opposite fuel tank through the motive-flow ejector pumps

Question 20

17. What is the function of the intertank valve?

Answer 20

To defuel the aircraft and to balance fuel

Question 21

18. What is the meaning of the “CB” indication in the boost pump switches?

Answer 21

This indicates that a boost pump circuit breaker has tripped on the power   
distribution box (PDB)

Question 22

19. Where is the location of the fuel boost pump circuit breakers?

Answer 22

On the power distribution box (PDB) in the forward radio rack, PRIMARY on the
ESS DC Bus and Alternate on the right main DC Bus