PP 18

What happens to pressure as air flows through a convergent nozzle?. Decreases. Increases.

What is the major function of the turbine assembly in a turbojet engine?. Supplies the power to turn the compressor. Compresses the air before it enters the combustion section.

What is the primary advantage of an axial-flow compressor over a centrifugal compressor?. Greater pressure ratio. Easier maintenance.

Newton’s First Law of Motion states: Every body persists in its state of rest…. To every action there is an equal and opposite reaction.

A turbine engine hot section is particularly susceptible to what kind of damage?. Cracking. Scoring.

The nozzle diaphragm of a turbine engine has the function of: Properly directing the gases onto the turbine buckets. Increasing the pressure of the exhaust gas.

The formula for thrust can be derived from: Newton’s 2nd law. Boyle’s 1st law.

A high oil temperature in a turbine engine is most likely due to: One or more main bearings in distress. An exceptional high compression in the oil pump.

The fan rotational speed of a dual axial compressor forward fan engine is the same as the: Low-pressure compressor. Accessory drive shaft.

What turbine engine section provides for proper mixing of fuel and air?. Combustion section. Compressor section.

In a gas turbine engine, combustion occurs at constant: Pressure. Volume.

A nozzle diaphragm upstream of the turbine wheel functions to: Increase gas velocity. Decrease gas velocity.

Where is the highest gas pressure in a turbojet engine?. At the entrance of the turbine section. At the outlet of the tailpipe.

When starting a turbojet engine: A hot start is indicated if EGT exceeds limits. A lean mixture is likely to cause a hot start.

In a twin-spool compressor system, the first-stage turbine drives the: N1 compressor. N1 and N2.

Cracks may occur in hot section components if marked with: Any of the above. A lead pencil.

What drives the fan in most turbofan engines?. The turbine that drives the low-pressure compressor. The turbine that drives the high-pressure compressor.

A hung start is indicated if the engine: Fails to reach idle RPM. EGT exceeds limits.

The two main inspection sections of a turbine engine are: Hot and cold. Combustion and exhaust.

The two basic elements of the turbine section are: Stator and rotor. Impeller and diffuser.

The two functional elements in a centrifugal compressor are: Impeller and diffuser. Turbine and compressor.

The most satisfactory turbine blade attachment method is: The fir-tree design. The tongue and groove design.

First engine instrument indication of a successful start: A rise in EGT. A decrease in EGT.

Who establishes TBO?. The engine manufacturer. Operator with TC.

Two common compressor types in jet engines: Centrifugal and axial. Axial and root.

A turboprop propeller: Accounts for 75–85% of thrust. Is governed at the same speed as the turbine.

Stress rupture cracks usually appear: Across leading or trailing edge at right angle. Across blade root.

Chamber type where case & liner are removed as one: Can-annular. Can.

Most common thrust reversers: Mechanical blockage and aerodynamic blockage. Convergent and divergent.

Stress rupture cracks on turbine blade leading edge suggest: Over-temperature condition. Air seal wear.