15.9 Lubricants & Fuels Flashcards
What are the 2 oil types?
Synthetic and mineral.
Why aren’t mineral oils used?
Lack stability.
Excessively volatility.
Thermal degradation.
What synthetic oil is used?
Ester based.
Known as third generation oils.
What functions does engine oil have?
Lubricating.
Cooling.
Cleaning.
Corrosion protection.
On what engines is Type 1 synthetic oil used on?
Old gas turbine engines.
On what engines is Type 2 synthetic oil used on?
Modern gas turbine engines?
On what engines is Type 3 synthetic oil used on?
Special military aircraft engines.
What are the positives of synthetic oil?
Better viscosity.
Thermal stability.
High pressure resistance.
What is the disadvantage of synthetic oil?
Expensive.
Define viscosity index.
The effect temperature has on oil viscosity.
Define viscosity.
The internal resistance against flow.
Define pour point.
Lowest temperature oil will visibly move.
What is the pour point of type 2 synthetic oil?
-57C
Define flash point.
Lowest temp oil will give enough vapour to flash when a flame is applied.
What is the flash point of type 2 synthetic oil?
250 C
Define pressure resistance.
Oil resistance at high temperatures.
What factors affect engine performance?
Oil foaming,
Rubber shelling,
Oxidation,
Thermal stability,
Corrosiveness,
Pressure,
Coking
What is engine coking?
Carbon residue in engine due to extreme heating.
What is the flash point of jet B fuel?
-20 C
What is the flash point of JP5 fuel?
65 C
What is the freezing point of JP5 fuel?
-48 C
Where is jet A fuel primarily used?
America.
Where is jet A1 fuel primarily used?
Europe.
Where is jet B fuel primarily used?
Cold temperatures.
