Section V - Engine Instrument Systems

Front 1

Where should the Thermocouple be installed on a reciprocating engine using a single probe cylinder head temperature system?

Back 1

On the hottest cylinder

Front 2

What does a tachometer indicate on a reciprocating engine?

Back 2

The engine RPM.

Front 3

What are the possible indications of an oil pressure, transmitter or indicator malfunction?

Back 3

A severe or sudden drop in oil pressure while oil temperature remains normal and the oil supply remains full.

Front 4

Is the aircraft electrical system required to power a cylinder head temperature gauge?

Back 4

No, a thermocouple is used as the electrical source

Front 5

During engine operation, where should the propeller control be set when checking manifold pressure?

Back 5

It should be set at low pitch or high RPM.

Front 6

What directly controls manifold pressure?

Back 6

Throttle opening and engine RPM.

Front 7

What does the manifold gauge indicate and how is it calibrated?

Back 7

It measures the absolute pressure in the engine manifold and it's calibrated in inches of mercury.

Front 8

Why is fuel flow monitored?

Back 8

To determine fuel consumption and engine performance.

Front 9

What unit of measure is generally used to indicate fuel flow?

Back 9

Pounds or gallons per hour?

Front 10

Name the basic components of a fuel indicator system?

Back 10

The transmitter and the indicator.

Front 11

What is the fuel pressure range on float-type carburetors?

Back 11

3 to 5 PSI

Front 12

Where would a carburetor air temperature bulb be located?

Back 12

In the ram air intake duct.

Front 13

What purpose does an oil analysis serve?

Back 13

Metal particles in the oil show normal and abnormal wear of the engine. This helps in evaluating the engine's internal condition.

Front 14

What inspection should be performed on an engine that has been in storage?

Back 14

An inspection to determine any corrosion damage.

Front 15

A weak cylinder is found during a compression check. What must be inspected?

Back 15

Inspect if the pressure is transmitted equality in all directions

Front 16

Name the major components in a gas turbine engine?

Back 16

The air inlet, compressor section, combustion section, turbine section, exhaust section, gearbox section, and the accessory section.

Front 17

Explain the main difference and advantage of turbofan over turbojet engines?

Back 17

Turbofan engine uses a fan to bypass some air around the engine core to provide thrust. The advantage is that this provides additional thrust without increasing fuel flow.

Front 18

Name the mahor components in a gas tub and engine?

Back 18

The air inlet compressor section, combustion section, turbine section, exhaust section, the gearbox, and accessory section.

Front 19

What determines the amount of air flow through a turbine engine?

Back 19

The forward speed of the aircraft, the compressor speed, and air density.

Front 20

Name the two types of compressors commonly used in turbine engines?

Back 20

Axial and centrifugal flow compressors.

Front 21

Name two different methods for attaching turbine engine rotor blades to the rotor disks?

Back 21

Dove tail type root, bulb type root, or Fir tree type root.

Front 22

What is a split compressor system?

Back 22

A system that is connected to the turbine section with two rotor shafts one inside the order. Also known as dual or twin spool compressors.

Front 23

What are the different types of combustion chambers used in turbine engines?

Back 23

Can, Annular, Can-annular, and Reverse flow annular.

Front 24

What prevents the combustion chambers from burning?

Back 24

Cooling air inside of the liner

Front 25

What is the purpose of the interconnecting tubes attached between can-type combustion chambers?

Back 25

For flame propagation during start.

Front 26

What functions do axial flow turbine nozzles perform?

Back 26

Direct the mass airflow to drive the turbine rotor at a specific angle.

Front 27

How is thermal stress relieved on a turbine disc?

Back 27

My directing bleed air unto the face of the disc, or by grooves cut into the disc.

Front 28

What are carbon seals used for in turbine engines?

Back 28

They are used as oil seals for rotor shaft bearings.

Front 29

What is shaft horsepower?

Back 29

It is the indication of the torque developed by a turboshaft or turboprop engine.

Front 30

Name the main components of a typical APU?

Back 30

Small Power turbine for power, bleed air, and electrical generators.

Front 31

What is the greatest demand placed on an APU?

Back 31

When supplying bleed air.

Front 32

How is an AP you generally started?

Back 32

With it's own electrical starter and battery power

Front 33

Where does the AP you get its fuel supply?

Back 33

From the aircraft's main fuel tanks.

Front 34

At what speed does a gas turbine APU operate. And how is this speed maintained?

Back 34

At its rated speed regardless of electrical or pneumatic load imposed. Fuel control automatically adjusts the fuel flow to maintain the rated speed.

Front 35

What is used to prevent a heavily loaded APU from exceeding Its maximum EGT?

Back 35

A load control valve modulates the pneumatic load to maintain EGT within limits.

Front 36

How is an APU shut down and why is this procedure used?

Back 36

By closing the bleed air valve to unload the APU, it runs for a specific amount of time to allow the EGT to cool and stabilize. This cool down period is typically 3 minutes. If a heavily loaded APU is abruptly shut down without any cooling down. Damage could occur as a result of a thermal shock.

Front 37

What powers the variable inlet guide vanes used on some APUs to regulate the compressor intake air flow?

Back 37

Fuel pressure.

Front 38

What is fan blade Shingling?

Back 38

It is the overlapping of the mid span shrouds of the fan blade.

Front 39

When a turbofan or turbojet engine is shut down. What should a mechanic listen for during coastdown?

Back 39

Any rubbing sound or other unusual noises from the engine.

Front 40

Why are compressor washes performed and what methods are commonly used?

Back 40

To remove any contaminants from the compressor section and improve engine performance. The fluid wash and abrasive grit wash are the most common leaves methods.

Front 41

How can you tell if a turbofan or turbojet engine is out of trim?

Back 41

The exhaust gas temperatures at the target engine pressure ratio in power for takeoff will too high.

Front 42

Name the different types of compressor blade damage that may be found during inspection.

Back 42

Dents, cracks, galling, pitting scratches, burns, burrs gouges

Front 43

What kind of markers can be used to mark the parts in hot and cold sections during repairs?

Back 43

Layout dye, felt tip marker, or chalk.

Front 44

How does relative humidity affect turbine engines?

Back 44

It has a negligible effect on turbine engines.

Front 45

What criteria determines replacement of life limited turbine engine components?

Back 45

Cycles, hours, and/or calendar time.

Front 46

If turbine blades are removed from a turbine disc, why should they be re-installed in the same location?

Back 46

To maintain the balance of the turbine wheel.

Front 47

How are gas turbine engine tachometers calibrated?

Back 47

In percentage of RPM.

Front 48

On a turbine engine, what is the engine pressure ratio and what does it indicate?

Back 48

It is the ratio between the total inlet pressure and the total turbine exhaust pressure and it's used to indicate the thrust developed by the engine.

Front 49

On a turbine engine, what does exhaust gas temperature indicate and how is it obtained?

Back 49

Exhaist gas temperature is the average temperature of the turbine discharge gases. It is obtained by thermocouples placed near the turbine exit.

Front 50

Can the exhaust gas temperature system on a turbine engine be checked without running the engine?

Back 50

Yes, my checking the resistance of the thermocouples and circuits.