Aircraft Fuels and Lubricants
28 Questions
1 Views

Aircraft Fuels and Lubricants

Created by
@FaultlessMarsh8570

Questions and Answers

What is the main characteristic of a lubricating oil's viscosity?

  • Its rate of flow through an orifice at a standard temperature
  • Its rate of change in viscosity with temperature change (correct)
  • Its resistance to flow at a standard temperature
  • Its specific gravity
  • Compared to reciprocating engine oils, which characteristic is more prominent in turbine engine oils?

  • Higher flash point
  • Less tendency to produce lacquer or coke (correct)
  • Higher viscosity index
  • Greater demulsibility
  • What is the primary function of engine oil, apart from lubricating?

  • Cooling and sealing
  • Cooling, sealing, preventing corrosion, and cushioning shock loads (correct)
  • Cushioning shock loads and preventing corrosion
  • Preventing corrosion only
  • What determines the proper grade of oil to use in a particular engine?

    <p>Operating speeds of bearings</p> Signup and view all the answers

    What is specific gravity a measure of?

    <p>Weight of a substance compared to an equal volume of distilled water</p> Signup and view all the answers

    What is an advantage of mineral base lubricants over vegetable oil base lubricants in aircraft engines?

    <p>Chemical stability</p> Signup and view all the answers

    What type of lubricant is required for high tooth pressures and high rubbing velocities, such as occur with spur type gears?

    <p>E.P lubricant</p> Signup and view all the answers

    What is a desirable characteristic of turbine engine oil?

    <p>High flash point</p> Signup and view all the answers

    What is done to protect integral fuel tanks from corrosion due to micro biological contamination?

    <p>A biocidal additive is added to the fuel</p> Signup and view all the answers

    What is the ideal oil for achieving theoretically perfect engine lubrication?

    <p>The thinnest oil that will stay in place and maintain a reasonable film strength</p> Signup and view all the answers

    What parameter needs to be adjusted when switching to an alternate fuel in a turbine engine?

    <p>Fuel specific gravity setting</p> Signup and view all the answers

    Why is kerosene used as a turbine engine fuel?

    <p>It has more heat energy per gallon and lubricates fuel system components</p> Signup and view all the answers

    What is calorific value a measure of?

    <p>The amount of heat or energy in one pound of fuel</p> Signup and view all the answers

    What type of oil is commonly used in gas turbine engines?

    <p>Synthetic oil</p> Signup and view all the answers

    What does an oil spectroscope measure?

    <p>Contaminants suspended in the oil</p> Signup and view all the answers

    What factors affect the ignition of fuel in a turbine engine?

    <p>Both volatility and atomisation</p> Signup and view all the answers

    Why is kerosene preferred over gasoline in turbine engines?

    <p>Kerosene is less volatile and has good lubrication properties</p> Signup and view all the answers

    What happens to the weight of a tank of fuel when its specific gravity is increased?

    <p>It increases</p> Signup and view all the answers

    What is the temperature at which the Reid vapour pressure of a fuel is measured?

    <p>38°C</p> Signup and view all the answers

    Which of the following is affected by the specific gravity of fuel?

    <p>Aircraft range</p> Signup and view all the answers

    At what air/fuel ratio will kerosene burn effectively?

    <p>15:1</p> Signup and view all the answers

    What should be done with Prist or Biopor during use?

    <p>It is left and burnt with the fuel.</p> Signup and view all the answers

    What does D.E.R.D 2494 refer to?

    <p>Kerosene</p> Signup and view all the answers

    What does a high viscosity index indicate about oil viscosity?

    <p>It will not vary greatly with temperature change.</p> Signup and view all the answers

    What is the function of a fuel system icing inhibitor?

    <p>It prevents the water in the fuel from freezing.</p> Signup and view all the answers

    What is the likely outcome of using a lubricant recommended for lower temperatures in extremely high-temperature conditions?

    <p>The oil pressure will be lower than normal.</p> Signup and view all the answers

    Which measurement indicates the flow characteristics of oil through an orifice?

    <p>The time required for a specific volume to flow.</p> Signup and view all the answers

    What happens to oil pressure when an engine is run in extremely high temperatures with an inappropriate lubricant?

    <p>The oil pressure will be lower than normal.</p> Signup and view all the answers

    Study Notes

    Lubricants and Fuels

    Kerosene and Fuels

    • Kerosene burns effectively at an air/fuel ratio of 15:1.
    • D.E.R.D 2494 is a type of kerosene.
    • Kerosene has more heat energy per gallon and lubricates fuel system components, making it a suitable turbine engine fuel.

    Lubricants and Viscosity

    • Viscosity is the measure of a liquid's resistance to flow.
    • High viscosity index means the oil viscosity will not vary greatly with temperature change.
    • The time in seconds required for exactly 60 cubic centimeters of oil to flow through an accurately calibrated orifice at a specific temperature is recorded as a measurement of the oil's viscosity.
    • Viscosity index is based on the rate of change in viscosity with temperature change.
    • A high viscosity index is desirable in turbine engine oil.

    Functions of Engine Oil

    • Engine oil performs functions in addition to lubricating, including cooling, sealing, preventing corrosion, and cushioning shock loads.

    Oil Types and Characteristics

    • Mineral base lubricants have chemical stability, which is an advantage over vegetable oil base lubricants in aircraft engines.
    • Synthetic oil is usually used in gas turbine engines.
    • An E.P lubricant is required for high tooth pressures and high rubbing velocities in spur type gears.

    Fuel System and Corrosion

    • A biocidal additive is added to fuel to protect integral fuel tanks from corrosion due to micro-biological contamination.
    • Specific gravity of fuel affects aircraft range; a higher specific gravity means a greater weight of fuel for a fixed volume, resulting in a greater range.

    Turbine Engine Performance and Fuel

    • Calorific value is the amount of heat or energy in one pound of fuel.
    • Ignition of fuel depends on both volatility and atomisation.
    • Kerosene is used instead of gasoline because it is less volatile and has good lubrication properties.

    Oil Analysis and Contaminants

    • An oil spectroscope measures contaminants suspended in the oil.
    • Oil sampling by spectrometer analysis is used to detect contaminants in the oil.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Quiz on aircraft fuels and lubricants, including kerosene air/fuel ratios and Prist/Biopor usage in gas turbine powerplants.

    More Quizzes Like This

    Use Quizgecko on...
    Browser
    Browser