Engine Fuel Metering Systems Flashcards
Why do aircraft fuel metering systems for reciprocating 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 ratio of 12 to 1 represent?
Represents an air to fuel ratio mixture of 12 pounds of air and 1 pound of fuel
What is the function of a float carburetor?
The float carburetor function is to measure airflow through the engine, induction system, and dispense the appropriate amount of gasoline into the airflow for all engine operating parameters and condition. It also provide the fuel in state that is as vaporized as possible by the time the ignition occurs in the cylinders
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 reciprocating engine equipped with a float carburetor to hesitate momentarily when these throttle is rapidly advance from idle to full power?
A malfunctioning accelerator pump
Are the instruments installed in an aircraft suitable for use when trimming a turbine engine
No, a special 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 identification of a bypass condition
