Engine Instrument Systems Flashcards
What are three types of flow-indicating systems used for turbine engines?
Vane-type flow meters, synchronous mass-type flow meters, and electronic motorless mass flow meters.
What do mass flow systems measure?
The mass of the flow. This is affected by the density of the fuel which is in turn affected by the fuel temperature.
In what units is an electronic motorless mass flow meter system calibrated?
Pounds per hour of fuel flow.
What is indicated in a turbine engine if the fuel flow for all conditions is high?
If there are other instrument abnormalities, there are possibly damaged turbine components.
Who is authorized to repair a fuel flow indicating system?
The components can be repaired only by an FAA approved repair station certificated for the particular instruments.
Where can you find the electrical power requirements for a fuel flow indicating system?
In the aircraft maintenance manual.
Where in the fuel system is the fuel flow transmitter located?
Between the fuel control and the fuel nozzles.
What kind of indicating system is used to measure oil temperature in a small, single-engine, general aviation airplane?
A sealed system in which a bulb, partially filled with a highly volatile liquid, is installed inside the oil strainer. The bulb is connected to a pressure gage by a copper tube. The pressure of the gas above the liquid is proportional to the temperature of the oil that surrounds the bulb, and the pressure gage is calibrated in terms of temperature.
What type of instrument system is used for measuring cylinder-head temperature and exhaust gas temperature?
A thermocouple system.
What kind of electrical instrument system is used for measuring oil temperature?
A ratiometer-type system.
What should a thermocouple cylinder-head temperature indicator read when the engine is cold?
The same as the outside air temperature gage.
What is critical in the installation of the thermocouple leads for a cylinder-head temperature indicator, the length of the leads or their resistance?
The resistance is critical, it must have the resistance specified on the indicator. This is usually 2 or 8 ohms.
What should a ratiometer temperature indicator read when the electrical power is off?
The pointer should be off scale on the low side.
What kind of tachometer is used on most small single-engine airplanes?
A magnetic drag tachometer that is similar to an automobile speedometer.
What would likely cause the pointer of a magnetic drag tachometer to oscillate?
Either a dry cable connecting the indicator to the engine, or a kink in the cable housing.
