Fuel Flashcards
How does fuel reach the collector tanks in each wing?
Gravity flow through flapper valves and when the engines are running through a scavenge ejector
How many water drain valves are there in each wing?
Three (Six total)
Where are the water drain valves located?
- Collector tank
- Wing tank
- Surge tank
What is the purpose of the NACA scoop?
Provides static ventilation of the tanks. Relieves air pressure differential caused by refueling, thermal expansion, or variation of altitude during flight.
What is the purpose of the surge bay?
Provide additional expansion volume to prevent fuel spillage.
How much fuel does the surge bay hold?
8 gallons or 53.6 pounds of fuel
The engines are provided fuel from which tank?
Collector tank
Fuel for the APU is provided from which tank?
Right collector tank
What feeds the APU line fuel?
Right standby pump or the right ejector
Where are the ejectors located?
Bottom of the collector tanks
What provides the motive flow for the ejectors to operate?
High pressure output of the engine driven fuel pumps
Where are the scavenge pumps located?
Lowest inboard point of each wing tank
What is necessary for the scavenge pumps to operate?
Motive flow output of fuel from the engine driven high pressure fuel pumps
Where is the engine fuel shutoff valve?
Forward of the engine rotor burst area
Where is the fuel heater/oil cooler located?
Engine accessory gearbox
The purpose of the standby fuel pumps are … (4)
- Provide pressure during engine start
- Provide fuel pressure in the event of an ejector failure
provided the standby pump switch is in L/R AUTO - Provide fuel to the APU line
- Crossfeeding of fuel
Should pressure return to the ejector output after failing to deliver sufficient pressure, the standby boost pump will remain on for …
An additional 10 seconds
How many fuel quantity probes are located in each wing tank?
Nine
What controls each side of the fuel system?
One channel of a dual-channel computer. If one side channel fails, the other channel automatically assumes control
What provides aircraft attitude to each channel of the fuel computer?
AHRS (IRS)
What determines fuel quantity in the tanks? (4)
- Fuel density
- Fuel probe readings
- Aircraft attitude and acceleration
- WOW signal
The fuel temperature probe is located …
Right wing tank
What provides a cutoff signal to the refuel valve when the tank is full?
Fuel level sensor at the top of each wing tank
What is displayed on the Fuel Synoptic Page if an input value is invalid?
Magenta dashes
A green fuel temperature is indicated above the right wing quantity at what temperature?
Above - 38C
A WING FUEL TEMP LOW caution comes on …
Below - 38C
