COMPLETE QUESTIONS AND ANSWERS
◉ What is one function of the nozzle diaphragm in a turbine engine?
Answer: To direct the flow of gases to strike the turbine blades at the
desired angle.
◉ What is the profile of a turbine engine compressor blade? Answer:
A reduced blade tip thickness.
◉ The fan rotational speed of a dual axial compressor forward fan
engine is the same as the? Answer: Low-pressure compressor.
◉ What does the abbreviation Pt7 mean in turbine engine
terminology? Answer: The total pressure at station No. 7.
◉ How should the blending of blades and vanes in a turbine engine
be performed? Answer: Parallel to the length of the blade using
smooth contours to minimize stress points.
◉ What turbine engine section provides for proper mixing of the
fuel and air? Answer: Combustion section.
,◉ In a gas turbine engine, combustion occurs at a constant? Answer:
Pressure.
◉ Which statement is true regarding jet engines? Answer: At the
higher engine speeds, thrust increases rapidly with small increases
in RPM.
◉ What happens to the low-pressure rotor of a two-spool
compressor at high altitudes? Answer: It will increase in speed as
the compressor load decreases in the lower density air.
◉ What is the function of turbine nozzle diaphragms in a gas turbine
engine? Answer: To increase the velocity of the heated gases flowing
past this point.
◉ Where is the highest gas pressure in a turbojet engine? Answer: In
the entrance of the burner section.
◉ What effect does an exhaust cone placed aft of the turbine have on
the pressure in the exhaust duct? Answer: It will increase and the
velocity to decrease.
◉ What is the function of the stator vane assembly at the discharge
end of a typical axial-flow compressor? Answer: To straighten
airflow to eliminate turbulence.
,◉ What is one of the major functions of the turbine section in a jet
engine? Answer: To drive the compressor section.
◉ What indicates a hot start when starting a turbine engine?
Answer: If the exhaust gas temperature exceeds specified limits.
◉ In the dual axial-flow or twin spool compressor system, what does
the first stage turbine drive? Answer: The N(2) compressor.
◉ What materials may be used to mark turbine engine components
exposed to high temperatures? Answer: Layout dye, commercial felt
tip marker, and chalk.
◉ What materials should not be used to mark turbine engine
components in the hot section? Answer: Lead pencils and wax or
grease pencils.
◉ What indicates a hung start in a turbine engine? Answer: The
engine fails to reach idle RPM.
◉ What are the two basic elements of the turbine section in a
turbine engine? Answer: Stator and rotor.
, ◉ What is the function of the exhaust cone assembly in a turbine
engine? Answer: To straighten and collect the exhaust gases into a
solid exhaust jet.
◉ What are the two functional elements in a centrifugal
compressor? Answer: Impeller and diffuser.
◉ What must be done after the fuel control unit has been replaced
on a turbine engine? Answer: Retrim the engine.
◉ What must be done to ball or roller bearings found to have
magnetism before use? Answer: They must be degaussed.
◉ What type of compressor contains vanes on both sides of the
impeller? Answer: Double entry centrifugal compressor.
◉ What is the first engine instrument indication of a successful start
of a turbine engine? Answer: A rise in the exhaust gas temperature.
◉ What does Pt7 represent in turbine engine maintenance manuals?
Answer: Turbine discharge total pressure.