Fuel Flashcards
How many Fuel tanks are there?
2 Integral Wing Tanks, each with a Collector & Surge Tank
In total, how many Fuel Pumps are there?
2 x Ejector Fuel Pumps
2 x AC Electric Fuel Pumps
6 x Scavenge (Ejector) Pumps
1 x DC Electric Fuel Pump (RIGHT Tank Only)
In the RIGHT wing, how many fuel pumps are there and what are they?
1 x Ejector Fuel Pump
1 x AC Electric Fuel Pump
3 x Scavenge (Ejector) Pump
1 x DC Electric Fuel Pump
What is the purpose of the Ejector Fuel Pump and how does it work?
Primary Fuel Pump
- Venturi Pump with no moving parts, powered by respective engine motive flow.
- Self sustained pump and does not require electrical power
- Does not work when the engines are not running
What Fuel Pump is used during Engine Start?
AC Fuel Pump
What is the purpose of the AC Fuel Pump?
Backup for the Ejector Pump in case of failure
AND
Supplies fuel to:
ONSIDE engine during Engine Start
CROSS-side engine during crossed operations
APU (When the engine is not running)
What supplies the Left AC Fuel Pump (AC Pump 1)?
AC BUS 1
What Supplies the Right AC Fuel Pump (AC Pump 2)?
AC ESS BUS
What is the purpose of the scavenge pumps?
Maintains the fuel level in the collector tank
AND
Ensures constant fuel flow to the engines
What is the purpose of the DC Fuel Pump?
Provides pressurised fuel for normal APU operation
AND
Fuel for engine start when AC power/AC Fuel Pump is not available
What is the electrical power supply for the DC Fuel Pump?
DC ESS BUS 2
Where is the Fuel Temperature sensed?
LEFT Fuel Tank
What is the maximum Fuel Imbalance?
360kg
When will the EICAS Message FUEL EQUAL-XFEED OPEN EICAS Message display?
When the Fuel Imbalance reduces to 45kg and the Crossfeed Valve is OPEN
What is the purpose of the Engine Fuel Shutoff Valve?
Prevents hazardous quantities of fuel from flowing into the engines/fire zones
What is the Normal position of the Engine Fuel Shutoff Valve?
OPEN
In what circumstances are the Engine Fuel Shutoff Valves CLOSED?
Actuation of the Fire Handles ONLY
Where is the Refuelling & Refuelling Control Panel & associated Pressurised Refuelling point Located?
Under the Right Wing
When is the Total Fuel Used Reset?
Automatically on first engine start
What is the purpose of the Fuel Crossfeed Valve?
Permits fuel supply to both engines for the purpose of correcting and avoiding fuel imbalance
When Selecting the Crossfeed Valve to LOW 1, what happens in the system?
Crossfeed Valve Opens
Activates AC PUMP 2
Both Engines are supplied fuel from Tank 2
When attempting Crossfeed, what happens if AC Pumps 1 & 2 are not in AUTO?
Fuel Crossfeed command is overridden
How is Fuel Transfer achieved?
The amount of fuel supplied to the LOW engine is higher than the fuel burn required, permitting transfer from 1 tank to another
When will the FUEL 1(2) LO LEVEL EICAS Message display?
400kg - When the fuel is below the Sensor Level
What happens if a scavenge pump stops transferring fuel to the collector box?
The fuel in the collector box flows out so that the fuel level inside it reaches the same level as the tank
Where is the collector tank in the wing?
Inboard
What is the purpose of the surge tank?
Collects any fuel that may have entered the vent system during manoeuvres
What is the purpose of the collector tank?
Keeps fuel pumps submerged, ensuring a constant fuel flow to the respective engines
How is Fuel Quantity Measured?
Electric Sensors
+ 1 Independent Fuel Low Level Sensor in each tank collector box
During an electrical emergency and the RAT in use, which fuel pump will be powered?
Right Wing AC Pump 2
How many External Magnetic Level Indicators (Dripsticks) are there?
6 (3 per wing)
What is the purpose of the Drain Valve?
Collects Water via gravity in each tank
What is the purpose of the vent system?
Ensures the differential pressure between the tank and the surrounding environment remains within limits
How is the fuel tank protected from over pressurisation?
High Capacity Pressure Relief Valve
What does a GREEN circle with a GREEN line diagonal to the flow line mean on the MFD Fuel Synoptic Page?
Fuel System Valve in Transit, with POSITIVE fuel pressure (would be WHITE if NO Fuel pressure)
Under what Engine N2 might it be normal to see no fuel flow in the fuel lines on the MFD Fuel Synoptic Page?
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