ATA 28 (FUEL SYSTEM) Flashcards
The crashlanding safety requirements that are required in this system contain what?
1) Impact-resistant fuel tanks,
2) Flexible fuel supply and hose system
3) Tolerance of load factors in all directions
4) Fuel shut-off to engines in case of emergency landing and/or fire.
Why are the fuel lines shrouded?
To prevent any fuel entering the the internal fuselage in the casecase of leakage.
What happens to any fuel leakage caught in the shrouded fuel lines?
The will be dumped overboard via the fuelage drain system.
How many fuel tanks are there and what are they called?
3 Fuel tanks in total. The suppy tank with 2 fuel cells, fwd main tank, aft main tank
How many equipment plates are there and where are they located?
5 in total. 2 equipment plates in the Supply and FWD main tank, 1 equipment plate in the AFT main tank.
What are the H145 fuel tanks made from?
Kevlar coated with polyurethane.
How many venitlation ports does the fuel system have?
2 per tank, 6 in total.
How are the fuel tanks connected?
By overflow channels.
What is located inside the Supply tank giving it two seperate fuel cells?
a bulkhead.
Which overflow channel is positioned higher?
The r/h fuel cell.
What is the purpose of the higher overflow channel in the r/h supply tank fuel cell?
to give 2-3 minutes more fuel to prevent a double engine flame out.
How many overflow channels between the FWD and AFT tank?
3
What is the purpose of the fuel ventilation system?
To keep the tank bladders unpressurized under all operating conditions, and to allow air to escape when refueling.
What does the Fuel vent system comprise?
Vent lines, refuel vent lines, Air-no-fuel Valves & expansion box
What is the purpose of the Fuel expansion box?
To allow expansion of fuel during temperture changes therfore keeping the system depressurised and recieve the dumped fuel from start up.
Where are the fuel prime pumps located?
On the Supply tank equipment plates.
Where are the transfer pumps located?
On the FWD main tank equipment plate.
What is the purpose of the Transfer pumps?
To keep feul in the supply tank.
What are the FWD main tank pumps called?
FWD and AFT transfer pumps.
What type of pump is in the AFT main tanks?
A jet type pump.
How many transfer pumps are required under full engine power?
One pump is sifficient enough to keep supply tanks full.
What type of valce is the shut-off valve?
Ball valve.
What happens when the prime pump is switched on?
Fuel is pumped to the fuel metering unit and ruturns into the expansion box. Purge operation stops around 40% N1.
Equipment plates installed to the supply tank are equipped with what?
A prime pump, a fuel quantity transmitter with low fuel sensor and a drain valve.
Equipment plates installed to the FWD Main tank are equipped with what?
A transfer pump, a fuel quantity transmitter and a drain valve.
Equipment plates installed to the AFT main tank are equipped with what?
A transfer pump, a fuel quantity transmitter and a drain valve.
What type of pump are the fuel pumps?
Canister type fuel pumps.
All four pumps are identical. True or False?
True
What is the outlet px of the fuel pump?
1 bar (14.5 PSI)
What is the maximum dry operating time of the fuel pump?
20 minutes
Where is the FWD transfer pump power supplied from?
ESS BUS 1
Wh0ere is the AFT transfer pump power supplied from?
SHED BUS 2
L/H prime pump power is supplied from where?
ESS BUS 1
R/H prime pump power is supplied from where?
ESS BUS 2
What creates the vacuum in the jet pump’s suction chamber to draw fuel from the aft main tank?
Motive pressure fuel tapped from the transfer pumps.
How is the fuel shut-off valve monitored?
By two means - Valve position & valve movement.
How is the shut-off valve position monitored?
By two micro switches.
When does the JET FUEL PUMP caution display?
FWD tank is less thann 15kg but the AFT is still more thn 10kg
Which engine will flame out first with low fuel?
Left engine
When are the prime pumps used?
Only on start up.
What is powered by ESS BUS 1&2?
Any system critical to flight.
Fuel shut off valve gives what type of notification on the MASTER LIST?
a Caution
What type of fuel probes are used in the H145?
Concentric capacitor type probes.
FUEL QTY DEG will appear on the master list when?
Failure of of one FWD tank transmitter, or AFT transmitter.
FUEL QTY FAIL will appear on the master list when?
If both FWD tank transmitters fail, or one supply tank transmitter fails
What weight does the fuel cells drop to to give yellow FUEL RESERVE ?
43kg in the l/h, 49kg in the r/h.
What weigth does the fuel drop to to give a red LOW fuel warning?
26kgW
hat type is the low fuel sensor?
Thermistor.
