NATOPS Chapter 2 Fuel System HSM-50

Question 1

The fuels system is a

Answer 1

Crashworthy, suction type, with a self sealing tank (lower 1/3)

Question 2

The main fuel tank capacity?

Left side components?

Right side?

Interconnect?

Answer 2

Has a capacity of 590 gallons (4012 lbs of JP-5).

• refueling, 2 high level shutoff floats, check valve, sump drain and a vent
• 2 check valves, sump drain, vent, APU fuel line, and fuel dump system

270-600 lbs each side

Question 3

Capacity of Aux Tanks?

PUMP/VALVE FAIL caution?

AUX FUEL TRANSFER FAULT?

Answer 3

120 or 113 gal each

Single valve or pump failure, the other valve or pump will pick up.

Total failure of both xfer/shutoff valves, dual transfer pumps, or FMCP logic

Question 4

During xfer of aux fuel if right cell fills faster than left you should

Answer 4

Monitor closely, if difference persists stop before right cell is full (approx. 1700lbs.)

Question 5

Do not initiate unmonitored manual transfer to the main tank from the aux tanks until the Main tank is below _________.

Answer 5

3200 lbs

Question 6

Emergency jettison of external fuel tanks via the ALL STORE JETT pushbutton is inhibited when?

Answer 6

Tank has less than 40 gal (272 lbs). SEL JETT must be utilized if below 272 lbs. (This means you will have to do it at 300lbs or less since the fuel gauge only reads in 50lb increments.)

Question 7

Tank fuel sequence?

During automatic transfer?

Answer 7

Main - right ext - left ext

Left - right (reverse of fill)

Question 8

At AUTO, the Fuel management logic will not begin until the Main fuel tank depletes to approx _______.

Answer 8

2640 lbs

Question 9

What is the minimum fuel dump rate?

Answer 9

approx. 800 lbs per minute

Question 10

Can you dump fuel on ground?

Answer 10

Yes. Not protected by WOW.

Question 11

If there is a ____ pressure differential, the HIFR will stop fueling.

Answer 11

20 psi

Question 12

During HIFR if the right cell fills faster than the left cell you should

Answer 12

Monitor closely, if it continues stop fueling before right cell is full (1700 lbs)

Question 13

What may the #1/#2 FUEL PRESS caution indicate?

Answer 13

Possible malfunction of the engine-driven fuel boost pump or an air leak in the fuel system

Question 14

When do you perform the Manual Fuel Transfer Check?

Answer 14

When main fuel tank capacity has decreased approximately 300lbs

Question 15

When you put the MASTER switch to REFUEL, what does the sequencing logic keep on?

Answer 15

the Precheck switches

Question 16

What does a Black BITE mean?

White BITE?

Answer 16

Go condition

NO GO condition

Question 17

What is prevented if you have a malfunctioning FMCP (with electrical power applied) causing activation of the precheck valves?

How can you correct this?

Answer 17

This prevents the ability to pressure refuel or HIFR

The FUEL MGMT CB on the COPILOT CB panel must be pulled to allow fueling

Question 18

How do the fuel probes work?

Answer 18

They are capacitance-type sensors that employ fuel as a dielectric to measure the weight of the fuel in each tank.

Question 19

When will a FUEL LOW caution appear?

Answer 19

When a fuel cell reaches 300lbs

Question 20

Fuel will dump from a dump port in the right fuel cell down to what?

Answer 20

The low level sensor, approx 300lbs per side

Question 21

How do you dump from the external tanks?

Answer 21

You have to set the FMCP MASTER and MODE switches to TRANSFER and MANUAL OVRD, then selec the FUEL DUMP switch

Question 22

Can you dump the main tank when the FMCP is in STOP FLOW?

Answer 22

yes

Question 23

What is the pressure of the pressure Refueling system?

Answer 23

55 psi

Question 24

Why is there a delay while refueling if you have a left external tank but not a right external tank installed?

Answer 24

Due to the FMCP logic determining that there is no right tank to fill

Question 25

How do you know there is a malfunction in the refueling system?

Answer 25

If full fuel flow continues while the precheck valves are being held in the precheck condition

Question 26

If both precheck valves fail

Answer 26

Proceed with caution to prevent rupture of the fuel tank