Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Engine Fuel
O&P(P)
| Question | Answer |
|---|---|
| Why do aircraft fuel metering systems for recip engines have mixture controls | The air density decreases as the aircraft ascends, causing the mixture to become richer. The mixture control allows the fuel to be decreased to maintain a fuel-air mixture ratio that produces the desired power |
| What does an air fuel mixture of 12:1 represent | This represents 12 pounds of air to 1 pound of fuel |
| What is the function of a float carburetor ? | The float carburetor's function is to measre airflow through the engine induction system and dispense the appropriate amount of gas into the airflow for all engine operating perimeters and conditions. It must also provide the fuel in a state that is as va |
| What two things are adjusted when setting the idling conditions on a float carburetor? | -Idling RPM by adjusting the throttle stop -Idling mixture by adjusting idle needle valve |
| What would likely cause a recip engine equipped with a float carburetor to hesitate momentarily when the throttle is rapidly advanced from idle to full power? | A malfunctioning accelerator pump |
| How does a pressure type carburetor operate? | Discharges fuel into the airstream at a pressure well above atmospheric. This results in better vaporization and permits the discharge of fuel into the airstream on the engine side of the throttle valve. With the discharge nozzles located at this point, t |
| What are the two types of fuel injection systems used on modern recip aircraft engines? | Teledyne Continental (TCM) system and Precision Airmotive (Bendix) system |
| What is used in the TCM fuel injection system to control the amount of fuel sent to the nozzles? | The engine speed determines the injector pump output pressure. The relief valve determines the fuel for low-speed operation, and the adjustable orifice determines the fuel for high-speed operation |
| What is used in the Precision Airmotive system to control the amount of fuel sent to the nozzles? | The mass of the air entering the engine acts on an air diaphragm that controls a servo ball valve in the line between the regulator and the flow divider |
| What is a FADEC | A full authority digital electronic control is a high precision digital electronic fuel control that cunctions during all engine operations. It includes the Electronic engine control and functions with the flight management computer to measure the fuel t |
| Does a turbine engine controlled by a FADEC require manual trimming | No, this is done by the FADEC |
| What are the basic principles of a hydromechanical fuel control | Has no electronic interface assisting in computing or metering the fuel. Generally driven by gas generator gear train of the engine to sense engine speed. Other mechanical engine parameters that are sensed are compressor discharge pressure, burner pressur |
| What are two basic types of fuel nozzles | Simplex and Duplex configurations |
| Why does a duplex fuel nozzle usually require a dual fuel manifold | The duplex nozzle usually requires a dual manifold and a pressurizing valve or flow divider for dividing primary and secondary (main) fuel flow |
| What is the advantages of a duplex fuel nozzle | The duplex nozzles offers a desirable spray pattern for combustion over a wide range of operating pressures |
| What parameters are normally sensed by a turbine engine fuel control | -Power lever angle -Compressor inlet total temp -Compressor RPM -Burner pressure |
| What is meant by trimming a turbine engine | Adjusting the fuel control for the proper specific gravity of the fuel and for the proper idle and full throttle RPM |
| What are two types of electronic fuel controls for turbine engines | Supervisory electronic engine control and full authority digital electronic control |
| What position should the flight deck metering control (or fuel condition lever) be set to for starting a turbine engine | The normal starting sequence is: -Rotate the compressor with the starter -Turn the ignition on -Open the engine fuel valve, either by moving the throttle to idle by moving a fuel shutoff lever or turning a switch |
| What specifications are used to trim a turbine engine | The data plate specifications for the specific engine. This data was obtained when the engine was calibrated in the manufacturer's test cell |
| Where should ambient temp be measured when trimming a turbine engine | In a shaded area as near the engine inlet as is practical |
| When should a turbine engine be retrimmed | Anytime there is a decrease in engine thrust, and after any maintenance that the manufacturer specifies as requiring retrimming |
| Are the instruments installed in an aircraft suitable for use when trimming a turbine engine | No, a special analyzer/trimmer such as a JetCal should be used |
| Where are the fuel strainers normally located in an aircraft fuel system | Fuel strainers are located in the tank outlet, the main strainer is located at the lowest point in the fuel system, and there are strainers in the carburetor or fuel injection system |
| How can you tell when a fuel strainer for a turbine engine has been bypassed | There is an indicator button that will pop out. This button is usually painted red for easy identification of a bypass condition |
| What are two types of fuel heaters used in a jet transport aircraft | Air-to-fuel and oil-to-fuel exchangers |
| How are fuel lines often protected in an engine compartment | By wrapping the lines with a fire protection sleeve to protect from fire and abrasions |
| What is the purpose of a lay line (solid line or painted words) on a flexible fuel hose | To monitor fuel hose twist. Hoses should be installed without twisting |
| What kind of fuel boost pumps are normally installed inside the fuel tanks | Centrifugal pumps |
| What are three functions of the boost pump in the tank of a jet transport aircraft | -To pressurize the fuel in the line between the tank and the engine driven pump -To transfer fuel from one tank to another to balance the fuel load -To pump fuel from the tank into the dump chute when fuel is being dumped |
| What is meant by a compensated fuel pump | It is a fuel pump that senses the ambient air pressure and maintains the fuel pressure a specific amount above this air pressure |
| What are two types or categories of engine driven fuel pumps | Nonconstant displacement and nonpositive displacement |
| What are the three basic types of valves used in fuel system | Cone-type, poppet-type, and gate valves |
| What are the three most common types of fuel filters | Micron filter, Wafer filter, and Plain screen mesh filter |
| Why do some aircraft filters have a relief valve | If the fuel screen, or filter becomes clogged, the relief valve will allow fuel to continue to flow to the engine |
| Where are fuel drains located in an aircraft engine | Turbine engines, combustion chambers have a drain valve that drains fuel that accumulates in the combustion chamber after each shutdown, or any fuel that may have accumulated during a false start. Many recip engines have drain valves in the intake manifol |
Created by:
tbarth
Popular Aviation sets