GTS MOD2 Aircraft Fuel Control Units

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What are some factors that fuel control units take into account?

Combustion pressure, aircraft speed, and propeller blade angle

Power lever angle, turbine gas temperature, and aircraft speed

Inlet air temperature, engine RPM, and combustion pressure (correct)

Inlet air pressure, propeller blade angle, and engine speed

Why does the FCU on a turbo-propeller engine need to make allowance for propeller blade angle?

To regulate the high pressure compressor

To increase fuel flow during acceleration

To maintain constant engine speed during changing propeller loads (correct)

To control the accessory gearbox

What is a key consideration during the transient states of acceleration and deceleration?

Preventing compressor stall

Maintaining constant engine speed (correct)

Achieving the most rapid acceleration possible

Using more fuel than allowed limits

Why is it necessary to balance fuel flow changes during deceleration?

To prevent lean flameout Signup and view all the answers

What drives the FCU on a single spool engine?

Accessory gearbox Signup and view all the answers

Why must the FCU on dual and triple spool engines be driven by the high pressure compressor?

To effectively control the fuel flow Signup and view all the answers

What undesirable conditions can occur if too much fuel is used during acceleration?

Temperature limits exceeded Signup and view all the answers

Why is close control of fuel needed during acceleration and deceleration?

To maintain constant engine speed Signup and view all the answers

What is the main purpose of an integrated fuel flow system?

To display fuel used and fuel flow using a single instrument Signup and view all the answers

Which component of the fuel flow transmitter imparts swirl and angular velocity to the fuel?

Motor-driven impeller assembly Signup and view all the answers

What is the function of the two pick-off assemblies in the fuel flow transmitter?

To provide an angular reference point Signup and view all the answers

How are the outer drum and impeller in the fuel flow transmitter connected?

Through a magnetic coupling Signup and view all the answers

Which component in the fuel flow system is responsible for driving the impeller assembly at a constant speed?

Motor-driven impeller assembly Signup and view all the answers

What happens to the magnets in the pick-off assemblies under zero fuel flow conditions?

They align with each other Signup and view all the answers

What is the role of the housing in the fuel flow transmitter?

To contain the motor-driven impeller assembly and flow metering chamber Signup and view all the answers

In an integrated fuel flow system, why are both fuel used and fuel flow displayed using a single instrument?

To reduce complexity for operators Signup and view all the answers

What is the main function of a supervisory electronic engine control system?

Limiting fuel flow through a hydromechanical fuel control Signup and view all the answers

Which signals does the control amplifier in the supervisory electronic engine control system receive?

Turbine gas temperature (TGT), N1, and N2 Signup and view all the answers

At what point does the electronic circuit in the control system start to function as a fuel limiting device?

Near full power Signup and view all the answers

How does the pressure regulator in this control system affect fuel flow to the spray nozzles?

By returning increasing amounts of fuel to the fuel pump inlet Signup and view all the answers

Which signals does the fuel flow regulator in this control system receive to regulate fuel flow to the engine?

High speed compressor (N3), gas path pressure (P1, P2, P4), and power lever position Signup and view all the answers

What does the control system do until near full power is reached?

Acts as a hydromechanical unit Signup and view all the answers

Which component regulates fuel pressure at the fuel pump in this system?

Pressure regulator Signup and view all the answers

What does the governor bellows pressure (Py) control?

Opening of the governor valve Signup and view all the answers

What initiates the closing of the governor valve during acceleration?

Input force from the power lever Signup and view all the answers

How do pressures Px and Py change when the governor valve is closed?

Both increase Signup and view all the answers

What happens to the metering valve when pressure Px increases?

Moves towards open Signup and view all the answers

How is fuel flow matched with airflow through the engine in the system design?

Ensuring acceleration without risk of stall or surge Signup and view all the answers

What is evacuated in the acceleration bellows assembly to provide an absolute pressure reference?

Acceleration bellows assembly Signup and view all the answers

What occurs when the desired RPM is reached by the governor?

Maintains on-speed RPM Signup and view all the answers

How does the acceleration bellows assembly respond to a rise in RPM?

Moves metering valve towards open Signup and view all the answers

What type of system is used for engine control in a supervisory engine electronic control?

Fuel management system Signup and view all the answers

Which of the following is NOT a functional difference between a supervisory engine electronic control and a FADEC engine fuel management system?

System integration Signup and view all the answers

What is the primary function of a FADEC engine fuel management system?

Management of fuel flow and ignition Signup and view all the answers

In comparison to a FADEC engine fuel management system, what control aspect does a supervisory engine electronic control primarily focus on?

Engine performance monitoring Signup and view all the answers

Which component is more emphasized in a FADEC engine fuel management system compared to a supervisory engine electronic control?

Ignition systems Signup and view all the answers

What aspect of engine control does a supervisory engine electronic control prioritize over a FADEC system?

Performance monitoring Signup and view all the answers

When comparing a supervisory engine electronic control and a FADEC system, which one is more focused on real-time adjustments during operation?

FADEC system Signup and view all the answers

What distinguishes the functionality of a FADEC engine fuel management system from that of a supervisory engine electronic control?

Regulation of fuel-air mixture Signup and view all the answers