Module 11 Flashcards
What is the function of the Shutoff Valve(Spar Valve)
Turns off Hydraulics, Electrics, and pneumatics
Used by maintenance whenever the fuel line is disconnected
What is the function of the Fuel pump?
Single stage pump delivers unmetered fuel to the FCU.
Two stage pumps are a single assembly mounted to the accessory gearbox-1st stage is impeller type
-2nd stage is gear-type
What do fuel heat exchangers do?
Heat cold-soaked fuel from the tanks to prevent ice formation
Medium for heating is Engine Bleed Air and Engine Oil
Where are Fuel filters usually found
1) The Fuel supply to the pump
2) Between the pump and the FCU
3) In the Fuel Nozzles (Last chance filters)
How does the FCU work?
Flight deck input commands received by the FCU are Power(Thrust) and Fuel Shutoff
It minimizes the need for the flight crew to constantly adjust the thrust levers to compensate for changing operating conditions
What do the fuel manifolds do?
Delivers fuel to the fuel nozzles for combustion
What are the two types of fuel manifolds?
Single Manifold
Dual Manifold
What is the function of fuel nozzles?
Atomize fuel to provide efficient combustion
What are the types of fuel nozzles?
Simplex and Duplex
What is the function of the Pressurizing and Dump Valve/Flow Divider?
1) Schedule primary and secondary fuel flow to the nozzles
2) Provide positive fuel cutoff at engine shutdown
Where are Drain Valves installed?
In the fuel delivery system to ensure that all fuel is removed after engine shutdown
- Manifold dump valve(Low point of the fuel manifolds)
- Combustor Drain Valve
What are the different types of Fuel Control Systems?
Hydromechanical
Hydropneumatic
Supervisory EEC
FADEC
How does the Hydromechanical Fuel Control System work?
Single lever input controls thrust and fuel shutoff
How does the Hydropneumatic Fuel Control System work?
Similar to Hydromechanical, but uses the governors
How does the Supervisory EEC Fuel Control System work?
Electronic Engine Control limits engine parameters from exceeding
