PT2240 Exam PART 1 of 5 Questions And
Answers New Review 2023/2024
1. Hydromechanical
2. Hydromechanical/electronic
3. Full Authority Digital Engine (or Electronics) Control (FADEC)
Gas turbine engine fuel controls can be divided into three basic groups:
1. computing
2. metering
Fuel controls have two sections to provide the correct fuel flow for the engine:
gas generator gear train
Hydromechanical fuel controls are generally driven by the _______________ of the
engine to sense engine speed.
1. Engine speed
2. compressor discharge pressure
3. burner pressure
4. exhaust temperature
5. inlet air temperature and pressure
Mechanical engine parameters that are sensed by the Hydromechanical fuel controls
are:
cams and servo valves
With Hydromechanical fuel controls, once the computing section determines the correct
amount of fuel flow, the metering section delivers the fuel to the engine fuel system
through the use of ______________________.
1. pressurize the fuel
2. meter fuel flow
3. deliver atomized fuel to the combustion section of the engine
The 3 basic functions of the engine fuel system are:
Electronic Fuel Control Unit
EFCU
Electronic Engine Control
EEC
thrust setting, speed governing & acceleration, and deceleration limiting
EFCU performs the functions of _______________________________ through EFCU
outputs to the fuel control assembly in response to power lever inputs.
1. Fuel pump
2. Pressure regulating valve
3. Single metering valve
4. Fuel shut off valve
The fuel metering section consists of:
servo motors
With Hydromechanical fuel controls, fuel flow is set by ______________________.
EEC
The fuel metering device meters the fuel using only outputs from the __________.
, computing & metering
Fuel controls have two sections,______________, and ____________________, to
provide the correct fuel flow for the engine.
gas generator
the hydromechanical interface is generally driven by the ______________ gear train of
the engine to sense engine speed.
fuel metering
The ______________ section consists of a fuel pump, a pressure regulating valve, a
single metering valve, and a fuel shutoff valve
constant pressure differential
To meter fuel by weight properly, the system must maintain a ____________________.
pressure-regulating valve
To maintain a constant pressure differential across the metering valve, a
______________________________ uses a diaphragm exposed to pump pressure on
one side and metered fuel pressure on the other.
computing section
The ________________ monitors power lever position, engine speed, burner pressure
and engine inlet pressure to control the amount of fuel permitted through the metering
jet to the engine
- power lever position; and
- pressure at the engine inlet and within the burners.
A typical fuel metering valve uses a tapered shaft to meter the fuel flow based on
___________ and the ___________________________________.
minimum-flow stop
To ensure adequate fuel flow during idle power settings, the main metering valve has a
____________________ that prevents the metering valve from closing too far and
causing erratic pressure fluctuation across the metering valve during idle operations.
fuel shutoff valve
Because the minimum flow stop prevents the metering valve from completely stopping
the flow of fuel to the combustors, a ____________________ is required to provide a
positive means of stopping the flow of fuel for engine shutdown.
mechanically, electrically, or pneumatically.
A cockpit lever controls the fuel shutoff valve either
___________________________________
computing
The _____________ section of the FCU is responsible for positioning the metering
valve to obtain the appropriate power output and to control the rate of acceleration and
deceleration.
- a speed-sensitive governor,
- a servo valve, and
- two pressure-sensitive bellows
A typical computing section uses:
- the supervisory engine control system
- and the full-authority control system.
Currently, two types of electronic engine controls are in use:
supervisory EEC
Answers New Review 2023/2024
1. Hydromechanical
2. Hydromechanical/electronic
3. Full Authority Digital Engine (or Electronics) Control (FADEC)
Gas turbine engine fuel controls can be divided into three basic groups:
1. computing
2. metering
Fuel controls have two sections to provide the correct fuel flow for the engine:
gas generator gear train
Hydromechanical fuel controls are generally driven by the _______________ of the
engine to sense engine speed.
1. Engine speed
2. compressor discharge pressure
3. burner pressure
4. exhaust temperature
5. inlet air temperature and pressure
Mechanical engine parameters that are sensed by the Hydromechanical fuel controls
are:
cams and servo valves
With Hydromechanical fuel controls, once the computing section determines the correct
amount of fuel flow, the metering section delivers the fuel to the engine fuel system
through the use of ______________________.
1. pressurize the fuel
2. meter fuel flow
3. deliver atomized fuel to the combustion section of the engine
The 3 basic functions of the engine fuel system are:
Electronic Fuel Control Unit
EFCU
Electronic Engine Control
EEC
thrust setting, speed governing & acceleration, and deceleration limiting
EFCU performs the functions of _______________________________ through EFCU
outputs to the fuel control assembly in response to power lever inputs.
1. Fuel pump
2. Pressure regulating valve
3. Single metering valve
4. Fuel shut off valve
The fuel metering section consists of:
servo motors
With Hydromechanical fuel controls, fuel flow is set by ______________________.
EEC
The fuel metering device meters the fuel using only outputs from the __________.
, computing & metering
Fuel controls have two sections,______________, and ____________________, to
provide the correct fuel flow for the engine.
gas generator
the hydromechanical interface is generally driven by the ______________ gear train of
the engine to sense engine speed.
fuel metering
The ______________ section consists of a fuel pump, a pressure regulating valve, a
single metering valve, and a fuel shutoff valve
constant pressure differential
To meter fuel by weight properly, the system must maintain a ____________________.
pressure-regulating valve
To maintain a constant pressure differential across the metering valve, a
______________________________ uses a diaphragm exposed to pump pressure on
one side and metered fuel pressure on the other.
computing section
The ________________ monitors power lever position, engine speed, burner pressure
and engine inlet pressure to control the amount of fuel permitted through the metering
jet to the engine
- power lever position; and
- pressure at the engine inlet and within the burners.
A typical fuel metering valve uses a tapered shaft to meter the fuel flow based on
___________ and the ___________________________________.
minimum-flow stop
To ensure adequate fuel flow during idle power settings, the main metering valve has a
____________________ that prevents the metering valve from closing too far and
causing erratic pressure fluctuation across the metering valve during idle operations.
fuel shutoff valve
Because the minimum flow stop prevents the metering valve from completely stopping
the flow of fuel to the combustors, a ____________________ is required to provide a
positive means of stopping the flow of fuel for engine shutdown.
mechanically, electrically, or pneumatically.
A cockpit lever controls the fuel shutoff valve either
___________________________________
computing
The _____________ section of the FCU is responsible for positioning the metering
valve to obtain the appropriate power output and to control the rate of acceleration and
deceleration.
- a speed-sensitive governor,
- a servo valve, and
- two pressure-sensitive bellows
A typical computing section uses:
- the supervisory engine control system
- and the full-authority control system.
Currently, two types of electronic engine controls are in use:
supervisory EEC
