Fuel System

Question 1

What type of fuel system does the MH-60S have?

Answer 1

It is a crash worthy, suction-type fuel system with self-sealing tanks and breakway valves

Question 2

What kind of refueling does the fuel system allow?

Answer 2

• Pressure refueling
• Gravity refueling
• HIFR (Helicopter In-flight Refueling)

Question 3

What provisions does the fuel system allow for?

Answer 3

• Fuel priming
• Fuel dumping
• Fuel quantity and low level warnings

Question 4

What is the capacity of each main fuel tank?

Answer 4

180 gals (1224 lbs)

Question 5

How does the fuel prime system operate?

Answer 5

In the FUEL PRIME position:
* Allows fuel to enter all fuel lines prior to engine start
* With PCLs in LOCKOUT position – it opens the shutoff valves and allows fuel to enter the fuel lines

In the APU BOOST position:
* Opens the APU fuel shutoff valve and activates the prime/boost pump to send fuel to the APU

Question 6

How do you prime an engine?

Answer 6

Hold the respective engine PCL in LOCKOUT and select the FUEL PUMP switch in FUEL PRIME

Question 7

What is the maximum refueling pressure?

Answer 7

• 55 psi when refueling via the main receptacle
• 15 psi when refueling via the closed circuit adapter

Question 8

What are the primary fuels for the MH-60S?

Answer 8

• JP-5
• JP-8
• F-24
• TS-1

Question 9

Can fuel be directly dumped from an internal auxiliary tank?

Answer 9

No; fuel can only be dumped from the main fuel cells

Question 10

What can cause a FUEL PRESS caution to illuminate?

Answer 10

1. Fuel leak
2. Failure of the engine-driven fuel pump

Question 11

What sensor triggers the FUEL LOW cautions?

Answer 11

Thermister mounted on the fuel probes in each main cell trigger the caution @ 300 ± 15 lbs (when the condition is detected for more than 5secs)

Illuminates when the fuel low condition is detected for more than 5 secs and deactivates when it is not detected for a period of 20 secs

Question 12

When does a main tank’s individual fuel quantity tape on the MDs/FDs turn yellow?

Answer 12

When the main tank fuel quantity is 300lbs or less

This is via the fuel probes -> signal conditioner -> FMC -> MDs/FDs

Question 13

When does the total fuel quantity tape on the MDs/FDs turn yellow?

Answer 13

When the total fuel quantity is 600lbs or less

This is via the fuel probes -> signal conditioner -> FMC -> MDs/FDs

Question 14

At what rate does fuel transfer occur at?

Answer 14

350 lbs per min

Question 15

At what rate does fuel dumping occur at?

Answer 15

A minimum of 800 lbs per min

Question 16

How many dump/transfer pumps are on during fuel transfer?

Answer 16

Only one transfer/dump pump is on during fuel transfer

Question 17

How many dump/transfer pumps are on during fuel dumping?

Answer 17

Both transfer/dump pumps are on during dumping

Question 18

When is fuel dumping available?

Answer 18

Only when the aircraft is weight off wheels

Question 19

Describe the NATOPS Warning regarding nose-down ground operations.

Answer 19

Flameouts may occur with nose-down operations lasting longer than 10 minutes when boost pumps are off and using JP-5, JP-8, or equivalent fuels.

Question 20

What is the definition of a primary fuel?

Answer 20

A fuel that the aircraft is authorized to use for continuous unrestricted operation

Question 21

When refueling, how far should the aircraft be away from other aircraft or structures?

Answer 21

50 feet

Question 22

What is the definition of a restricted fuel?

Answer 22

A fuel that imposes operational restrictions on the aircraft

Question 23

When refueling, how far should the aircraft be away from an operating radar set?

Answer 23

75 feet

Question 24

When does the FUEL SPLIT caution appear? When does it go away?

Answer 24

It illuminates when the fuel difference between the main tanks is greater than 150 lbs.

It will remain illuminated until the fuel difference gets within 75 lbs.

Fuel splits of a 100lbs or greater should be balanced using XFD operations (assuming no internal aux tanks).

Question 25

What does FSII stand for?

Answer 25

Fuel System Icing Inhibitor

Question 26

If an aircraft is filled with fuel without FSII and has been in a heated hanger area, what should you do?

Answer 26

The aircraft should be launched within 1hr after being moved to the flight deck/turn-up area

Question 27

If an aircraft, filled with fuel without FSII, has been outside for more than an hour, what should you do?

Answer 27

The bulk fuel temperature should be checked

Question 28

What should you do if fuel is less than 0°C?

Answer 28

* Aircraft should be hangered until the bulk fuel temperature rises above 0°C **or** * Partially defueled and refueled with warm fuel so that the bulk temperature rises above 0°C