PHI GOM S-92A - FUEL

Question 0

Which tank supplies fuel to run the Auxiliary Power Unit (APU)?

Answer 0

1 (left) FUEL TANK

Question 1

How much fuel is unusable?

Answer 1

4.8 gallons (2.4 each side)

Question 2

What are the approved fuels for the S-92?

Answer 2

Jet A (JP-5)
Jet A-1 (JP-8)
Jet B (JP-4)
No. 3 Jet Fuel

Question 3

How much fuel can be loaded using pressure refueling in gallons and pounds?

Answer 3

764 gallons / 5175 pounds

Question 4

How much fuel can be loaded using gravity refueling in gallons and pounds?

Answer 4

713 gallons / 4830 pounds.

Question 5

What component controls which of the two prime pumps is used to prime the fuel system during engine start?

Answer 5

Maintenance Data Computer (MDC)

Question 6

What is the recommended pressure for refueling?

Answer 6

55 psig (120GPM)

Question 7

What is the maximum defuel rate?

Answer 7

90 GPM

Question 8

How is fuel quantity measured?

Answer 8

Two fuel quantity probes in each tank (4 total) send information to the Fuel Conditioning Unit computer which averages the two probes per tank and provides quantity information to the EICAS.

Question 9

What fuel level does the fuel low indication come on and what is the limitation?

Answer 9

215 +/- 45 pounds

No steady state pitch attitudes above 10 degrees or below 5 degrees.

Question 10

What does the caution

SOV 1 WRNG POSN indicate?

Answer 10

1 Fuel prime shutoff valve is in disagreement;

either open when it should be closed,
or closed when it should be open.

Question 11

During APU start with an inoperative MDC, will the fuel system be primed during start?

Answer 11

Yes, default pump is #1.

Question 12

Which electrical bus powers the fuel high level pre-check circuits?

Answer 12

Battery Utility

Question 13

Describe the fuel pre-check procedure for pressure refueling.

Answer 13

Begin pressure fueling and select PRI on the fuel precheck panel. Observe the flow of fuel stop indicating the high level sensor is operational. Release switch to NORM and allow fuel to flow, then select SEC on the precheck panel and observe the flow of fuel stop again indicating the secondary high level sensor is operational.

Question 14

When 1 hour of fuel remains, based on current fuel consumption, the fuel quantity symbology will change to _________?

Answer 14

Green/Yellow barber pole in color

Question 15

When the fuel quantity reaches _____ lbs of remaining fuel, the associated lettering and numbers turns _______?

Answer 15

215 +/- 45 lbs.

Yellow

Question 16

The fuel prime pump only runs when the _______ is on or during_____.

Answer 16

APU is on

Engine starting

Question 17

During pressure refuel will all fueling stop to both tanks if the right tank high level shut off activates?

Answer 17

No.
Fuel will stop for that tank and continue for the other.
MAINTENANCE MANUAL 28-21-00

Question 18

Why does the fuel system have a LOW level shutoff valve?

Answer 18

For pressure defuel

Question 19

When in crossfeed does the engine being started have positive prime pump fuel supplied or negative from the engine?

Answer 19

Negative
from the low pressure engine driven fuel pump.

Although a prime pump operates when each engine starts, the Prime SOV only opens to the engine being started when in DIRECT.

In Crossfeed the opposite Prime SOV opens. see RFM for Ref. Also, in the 28-00 Maint Manual page 620 you will see that a jumper has to be used during the #1 Engine prime fuel Crossfeed test so that the system thinks the #2 engine is starting.
Lastly, you can see this in the wiring diagram where the prime SOV relay is only powered by the on-side starter relay.

Question 20

Can the S-92 be pressure refueled without the battery switch on?

Answer 20

Yes, however PHI does not allow this.

The high level shutoffs/prechecks are on the Utility bus so the battery does not have to be on.