PTM Ch. 5 Fuel System Flashcards
Useable fuel
648 gal
4342 lbs
With boost pumps inoperative, how many many pounds of fuel indicated on the fuel quantity gauge for that tank will be unusable?
75 lbs
If the boost pumps are not used or are inoperable, wing dihedral will no longer keep the hopper tank full, if the XFER PUMP caution light comes on, how many pounds of fuel do you have left?
600-700 lbs. 75 lbs will remain in tanks however, that will be unusable.
With boost pumps on and XFER PUMP caution light will illuminate with how many pounds of fuel left?
75 lbs or 7.5 min of flight time.
If a fuel vent is closed, will fuel still be able to flow on that side?
Yes. The tanks are vented together and the other side will provide ventilation.
What prevents fuel from flowing back from hopper tank, forward, and aft collector tanks?
Flapper valves
High pressure pump has how much PSI?
980 psi in the engine.
How many fuel pumps do we have?
4 per side
2 boost pumps
1 low pressure
1 high pressure
How many gal are in hopper tank?
12 gal 81 lbs
How many unusable gal in hopper tank?
2 gal per side
Each main pump is powered from what essential bus?
It’s respective side’s essential bus.
Each Aux pump is powered by what essential bus?
The opposite side essential bus.
What controls the XFER PUMP light?
Float switch in the hopper tank
Is takeoff allowed with XFER PUMP illuminated?
No.
The crossflow line interconnects the left and right what?
Forward collector tanks
The motive flow for the crossflow fuel valve?
Electricity.
Where is the crossflow fuel valve?
In the crossflow line
When is the X-FLOW light illuminated?
When the valve is in motion or is stuck in between open/closed.
Max imbalance in Metro 23?
200 lbs
Max imbalance with DOWTY props
500 lbs
Max imbalance with McCauley props
> 2000 lbs of fuel = 200 lbs
<2000 lbs of fuel = 400 lbs
Where is the fuel shutoff valve?
Respective wheel well.
When you press the “test button” on the fuel quantity, how much fuel should you see?
1250 lbs. when you release the button they should go back to their respective amounts
How to balance fuel in flight:
Enter a slip- light wing down, rudder opposite
Press crossflow button
When tanks are equal press crossflow button again
Release slip when XFLOW is still lit.
Each Fuel shutoff valve is powered by what?
It’s respective bus, and will automatically transfer to opposite bus.
Max quantity that you can check with Magna stick?
1000 lbs.
The fuel pressure gauge indicates fuel pressure between what pumps?
Engine driven low pressure pump and engine driven high pressure pump.
What would a zero fuel pressure prior to engine start and a 15 to 20 psi lower than normal with engine in operation indicate?
Inoperative boost pump.
How much fuel can you put in before switching to other side?
125 gal
