Term
| Newton's first law of motion |
|
Definition
| A body at rest tends to remain at rest and a body in motion tends to continue in motion in a straight line unless caused to change its state by an external force |
|
|
Term
| Newton's second law of motion |
|
Definition
| The acceleration of a body is directly proportional to the force causing it and inversely proportional to the mass of the body |
|
|
Term
| Newton's third law of motion |
|
Definition
| For every action, there is an equal and opposite reaction |
|
|
Term
| Energy transformation cycle of a gas Turbin engine |
|
Definition
Intake
compression
combustion
exhaust |
|
|
Term
|
Definition
A reaction force measured in pounds
Action= acceleration of air mass
Reaction= Forward movement |
|
|
Term
|
Definition
Velocity increase = pressure decrease
Velocity decrease = pressure increase |
|
|
Term
|
Definition
Temperature.
Humidity.
Altitude.
Airspeed.
Engine rpm.
Fan efficiency.
Water injection.
Afterburner |
|
|
Term
|
Definition
0 ft altitude
59°F
29.92 in/hg (mercury) |
|
|
Term
| Four types of gas turbine engines |
|
Definition
Turbojet
Turbofan
Turboprop
Turboshaft |
|
|
Term
|
Definition
Heat exchanger- Engine oil or Bleed air
Fuel flows continuously |
|
|
Term
|
Definition
| Provides single spray pattern |
|
|
Term
|
Definition
2 independent discharge orfices,
(small & large)
Small orifice = Center- Primary fuel (idle)
Large orifice = around center- Secondary fuel
Can be single or dual line |
|
|
Term
|
Definition
Pressurization and Dump Valve
Usually used in fuel systems with dual line duplex nozzles
-pressurize fuel in primary and secondary manifolds
-empty or dump all of the fuel in the 2 manifolds upon engine shutdown |
|
|
Term
| What is the Brayton cycle? |
|
Definition
| Simultaneous / continuous intake, compulsion and compression at constant pressure |
|
|
Term
| The function of the turbine in a turbojet is to drive the ______ |
|
Definition
|
|
Term
| Determine engine that uses a separate turbine to drive a reduction gearbox, and / or propeller is a ________ engine |
|
Definition
|
|
Term
| What are three and villages of a turbofan over a turbojet engine |
|
Definition
More efficient / less fuel
Fan will divert FOD
Quieter
High thrust at low speeds |
|
|
Term
| The ratio of the amount of air that passes through the fan to that which flows through the core of the engine is called ________ |
|
Definition
|
|
Term
| Convergent subsonic air flow |
|
Definition
Velocity increases
Pressure decreases |
|
|
Term
| Divergent subsonic air flow |
|
Definition
Pressure increases
Velocity decreases |
|
|
Term
| Convergent supersonic air flow |
|
Definition
Velocity decreases
Pressure increases
Density increases |
|
|
Term
| Divergent supersonic air flow |
|
Definition
Velocity increases
Pressure decreases
Density decreases |
|
|
Term
| What is the cold section consist of |
|
Definition
|
|
Term
| What speed must the air entering the engine be? |
|
Definition
|
|
Term
| what are the two sections into which a gas turbine engine can be divided? |
|
Definition
|
|
Term
| Can let ducts are part of ________ |
|
Definition
|
|
Term
| Name two classifications of inlet ducts |
|
Definition
|
|
Term
|
Definition
| When an airfoil exceed its critical angle of attack |
|
|
Term
| What is the use of inlet guide vanes |
|
Definition
-Slightly reduces the amount of air flowing through the engine (to prevent compressor stall)
-Direct air to the first stage of the compressor at the proper angle.
-Used on axial flow turbine engines |
|
|
Term
| Two types of compressors with respect to air flow |
|
Definition
Centrifugal type.
Axial type |
|
|
Term
| Three types of compressors with respect to performance |
|
Definition
Single stage.
Two Stage.
Multiple stage. |
|
|
Term
| What is a compressor stall? |
|
Definition
| Occurs when the compressor blades angle of attack exceed the critical angle of attack, at this point smooth air flow is interrupted and turbulence is created with pressure fluctuations |
|
|
Term
|
Definition
| Reduced blade thickness at tip |
|
|
Term
| Three types of rotor blade roots |
|
Definition
|
|
Term
| What is compressor air supplied for |
|
Definition
Cabin pressurization.
Kevin heating.
Cabin cooling.
Cooling turbine inlet guide vanes
Cooling turbine wheel.
Deicing systems.
Anti-icing systems.
Pneumatic engine starting |
|
|
Term
| Where is the diffuser located? |
|
Definition
| Between the compressor and combustion chamber |
|
|
Term
|
Definition
Produces electricity and increases pressure
Divergent shape
Point of highest pressure in the engine |
|
|
Term
| Pressure of air passing through the compressor is a measure of _____ energy |
|
Definition
|
|
Term
| Air taken from the compressor to anti-ice the inlet duct is known as ______ air |
|
Definition
|
|
Term
| What are other uses for bleed air? |
|
Definition
Cooling
Pressurize cabin
A.c. |
|
|
Term
| Name two types of compressors used on turbine engines |
|
Definition
|
|
Term
| Name the three components of a centrifugal compressor |
|
Definition
Impeller
Diffuser
Compressor manifold |
|
|
Term
| Name the components of an axial flow compressor |
|
Definition
|
|
Term
| A compressor blade with a tip having a decreased thickness is known as _______ |
|
Definition
|
|
Term
| Two design features that may be used to prevent or minimize compressor stalls are |
|
Definition
|
|
Term
| Two variables that affect compressor stall are |
|
Definition
RPM
velocity of airflow
Through compression |
|
|
Term
| What is the Hot Section consist of? |
|
Definition
Combustion section
turbine section
exhaust section |
|
|
Term
Located directly behind the diffuser=
Where the fuel & air is mixed & burned= |
|
Definition
|
|
Term
| What does the combustion section consist of? |
|
Definition
One or more combustion chambers
a fuel injection system
an ignition system
an ignition source
a fuel drianage system |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Name 4 LRU's that could be found attached to a turbine engine gearbox. |
|
Definition
Hydraulic pump
Generators
Oil pump
Starter
Fuel Control Unit (FCU)
Boost pump
Fuel Pump
Oil cooler |
|
|
Term
| In addition to powering aircraft accessories, what other secondary function does the gearbox serve? |
|
Definition
|
|
Term
| On a dual spool turbofan, which rotor drives the accessory gearbox? |
|
Definition
|
|
Term
| What are 2 types of fuels used for turbine engines? |
|
Definition
|
|
Term
| what is the difference of the 2 turbine fuels? |
|
Definition
Jet A= primarily kerosene
Jet B= 70% gasoline, 30% kerosene |
|
|
Term
| Name the 3 types of turbine engine fuel nozzles. |
|
Definition
|
|
Term
| What are the 2 functions of the P&D valve? |
|
Definition
|
|
Term
|
Definition
1. Tank
2. Boost pump
3. Shut Off Valve (SOV)
4. Fuel Pump
5. Low Pressure Pump
6. Fuel Heater
7. Bypass
8. High Pressure Pump
9. Bypass
10. SOV (air)
11. Filter
12. Differential pressure switch
13. Bypass
14. Fuel Control
15. Fuel flow transmitter
16. oil cooler
17. P&D valve
18. Primary
19. Secondary
20. Nozzle
21. Fuel dump |
|
|
Term
|
Definition
Convergent Duct=
Velocity = Decreases
Pressure = Increases
Density = Increases
Divergent Duct=
Velocity = Increases
Pressure = Decreases
Density = Decreases |
|
|
Term
|
Definition
Convergent Duct=
Velocity = Increases
Pressure = Decreases
Divergent Duct=
Velocity = Decreases
Pressure = Increases |
|
|
Term
| An increase in airspeed will cause a turbojet engine's thrust to ______ |
|
Definition
|
|
Term
|
Definition
| Total pressure at station 2 |
|
|
Term
| Ducts in the diffuser of a turbine engine are _________ in shape. |
|
Definition
|
|
Term
| What are two types of turbine engine compressors? |
|
Definition
|
|
Term
| In turbine engine, the air that is used for combustion is known as __________ |
|
Definition
|
|
Term
| What is the most common type of turbine blade (shape) used on modern turbine engines? |
|
Definition
|
|
Term
| Between each row of rotating blades in a turbine engine compressor, there is a row of stationary blades which act to diffuse the air. these stationary blades are called __________ |
|
Definition
|
|
Term
| What is the primary factor which controls the pressure ratio of an axial-flow compressor? |
|
Definition
|
|
Term
| Name 3 types of combustion sections used in aircraft turbine engines. |
|
Definition
|
|
Term
| On an aircraft turbine engine, operating at a constant power, the application of engine anti-icing will result in ______________ |
|
Definition
Lower Thrust
Higher Temperature |
|
|
Term
| Name 4 main factors that affect thrust |
|
Definition
Temperature
Altitude
Air density
RPM
Air Speed
Fan Efficiency
Afterburner |
|
|
Term
| What is the purpose of a bell mouth inlet? |
|
Definition
| To allow smooth airflow into the engine at low speeds |
|
|
Term
| What are 4 uses for bleed air from a turbine engine? |
|
Definition
Cabin Pressurization
Cabin Heating
Cabin Cooling
Cooling turbine inlet guide vanes
Cooling turbine wheel
Deicing systems
Anti-icing systems
Pneumatic engine starting |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Name 2 types of Turbine engine oils. |
|
Definition
|
|
Term
| What type of oil system is typically found on turbine engines? |
|
Definition
|
|
Term
| Why do turbine engine manufacturers recommend servicing oil after engine shut down? |
|
Definition
|
|
Term
| Name 3 types of positive displacement pumps used for fuel or oil systems. |
|
Definition
|
|
Term
| What is the purpose of the thermostatic valve in a turbine engine cooler? |
|
Definition
controls the amount of oil that flows to the cooler
Oil cold – bypass valve open – oil will bypass the cooler
Oil hot – bypass valve closed – oil will flow through the cooler |
|
|
Term
| According to Federal Aviation Regulations, oil tank fillers on turbine engines must be marked with _________ |
|
Definition
|
|
Term
| Describe the operation of an indicating chip detector. |
|
Definition
| metal chips in oil are trapped. when build up or large enough chips are captured they bridge a gap in the mesh filter completing an electrical circuit and an indicating light is illuminated |
|
|
Term
| Name 2 types of oil seals used on a turbine engine. |
|
Definition
|
|
Term
| What is the primary purpose of the fuel to oil heat exchanger? |
|
Definition
|
|
Term
| What are 2 things that will happen if the oil filter becomes blocked? |
|
Definition
lights up warning light
bypass valve opens (bypassing filter completely) |
|
|
Term
| What is a Hot Tank oil system? |
|
Definition
| Oil is cooled after leaving tank (oil is hot in tank) |
|
|
Term
| What is the purpose of the dwell chamber of a turbine engine oil tank? |
|
Definition
| chamber where oil is temporarily stored to help eliminate bubbles and foam |
|
|
Term
| What color are turbine engine fuels? |
|
Definition
|
|
Term
| What is PRIST? What is it's purpose? How does it work? |
|
Definition
Fuel additive
-Prevents ice and bacterial contamination
--As the fuel temperature decreases, the additive combines with the water in greater concentrations. This combination will keep the freezing point of the water lower than the temperature of the fuel. |
|
|
Term
| Describe the operation of a cooled oil cooler/fuel heater. |
|
Definition
Heat Exchanger–Engine Oil or Bleed Air.
Fuel flows through continuously.
Activated manually or automatically. |
|
|
Term
| What is the airflow through the combustor divided into? |
|
Definition
|
|
Term
| Explain the Primary path of airflow through the combustor. |
|
Definition
25% to 35% of incoming air.
Passes through a set of swirl vanes, gives air a radial motion & slows velocity. |
|
|
Term
| Explain the Secondary path of airflow through the combustor. |
|
Definition
65% to 75% of incoming air
Secondary air for cooling |
|
|
Term
| What are the types of combustion chambers? |
|
Definition
Can type/ Multiple-can type
Annular or Basket type
Can Annular type |
|
|
Term
| What are the 4 basic parts of the Turbine section? |
|
Definition
|
|
Term
| What are the other names for the turbine Stators? |
|
Definition
Turbine nozzle
Turbine Guide Vane
Turbine nozzle Diaphragm |
|
|
Term
| What is the part with the hottest heat to metal temperature in a turbine engine? |
|
Definition
|
|
Term
| What does the turbine rotor consist of? |
|
Definition
Shaft
Turbine rotor or wheel |
|
|
Term
| What is the shape of Turbine Blades? Why? |
|
Definition
Airfoil shaped
Designed to extract the maximum amount of energy from the flow of hot gases |
|
|
Term
| What is the most common Turbine Blade attachment shape? |
|
Definition
|
|
Term
| What are the classifications of Turbine Blades? |
|
Definition
Impulse Type
Reaction Type
Impulse-Reaction Type |
|
|
Term
| What is the accessory gearbox powered by? |
|
Definition
| Engine's main power shaft |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| What are the ignition system Components? |
|
Definition
Transformer/ exciter box (2)
Ignition Lead (2)
Igniter (2) |
|
|
Term
|
Definition
Shell/Body
Insulator
Internal seals
Electode |
|
|
Term
|
Definition
|
|
Term
|
Definition
Starter-Generators
Combustion Starters
Gas turbine type
Cartridge type
Air Turbine
Direct Cranking Starter |
|
|
Term
|
Definition
Compressor speed
Engine Pressure Ratio
Turbine discharge pressure
Torquemeter
Fuel Flow indicator
Oil pressure gage
Oil teperature gage
Exhaust gas temperature - EGT
Engine Indicating & Crew Alerting System (EICAS) |
|
|
Term
| How is Compressor speed monitored? |
|
Definition
-Tachometer in % RPM
-Separate Tach for each compressor |
|
|
Term
| what is the engine pressure ratio? what does the EPR gauge indicate? |
|
Definition
Ratio of Turbine Discharge Pressure to Compressor Inlet Pressure
Indicates amount of thrust produced.
Pressure taken at Pt2 & Pt7 |
|
|
Term
| Turbine engine Starting Safety check |
|
Definition
Master Switch – OFF
Battery Switch – OFF
Landing Gear Handle – DOWN
Generator Switches – OFF
Starter Switch – OFF
Ignition Switch – Off (Circuit Breaker IN)
Power Lever - Cutoff |
|
|
Term
| Turbine engine starting Pre-Start Checks |
|
Definition
Ground Power – Verify correct voltage & air pressure.
Master Switch – ON
Battery Switch – ON
External Power Switch – ON
Fuel Boost Pump(s) – ON
Fuel Valve(s) Selected – OPEN
Low Fuel Pressure Light – OFF |
|
|
Term
| Starting a Turbine Engine |
|
Definition
Start Switch – Start
-Watch RPM indicator
25% RPM – Power Lever to IDLE Position
-Watch for Fuel Flow
-Watch EGT gage
-Watch oil pressure gage |
|
|
Term
|
Definition
If EGT exceeds allowable limits
(SHUT OFF FUEL IMMEDIATELY) |
|
|
Term
|
Definition
Engine Fails to accelerate or reach idle RPM
(shut down immediately) |
|
|
Term
| What do you do if a fire starts in the engine during start cycle? |
|
Definition
Cut off fuel
Continue motoring engine with the starter |
|
|
Term
| Engine shutdown procedure... |
|
Definition
Engine checks complete
Run engine at idle for 30 – 60 seconds
Power Lever – Cutoff
Fuel Valve(s) Selected – Closed
Fuel Boost Pump(s) – OFF
External Power Switch – OFF
Battery Switch – OFF
Master Switch - OFF |
|
|
Term
|
Definition
To drive an electric generator
Supplies bleed air for heating, cooling, anti-ice, and engine starting |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| Airworthiness limitations |
|
|
Term
|
Definition
|
|
Term
| subsonic planes have what type of exhaust cone? |
|
Definition
|
|
Term
| Any type of maintenance that can be done while the engine is installed on the aircraft. |
|
Definition
|
|
Term
| Maintenance the requires the engine to be taken off the aircraft. (normally performed at an overhaul facility) |
|
Definition
| Shop Maintenance / Heavy Maintenance |
|
|
Term
| Adjust fuel control for maximum rated thrust |
|
Definition
|
|
Term
|
Definition
Fan and booster
High pressure compressor
Combustor
High pressure turbine
Low pressure turbine
Accessory drive |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| Airworthiness limitations |
|
|
Term
|
Definition
|
|
Term
| subsonic planes have what type of exhaust cone? |
|
Definition
|
|
Term
| Any type of maintenance that can be done while the engine is installed on the aircraft. |
|
Definition
|
|
Term
| Maintenance the requires the engine to be taken off the aircraft. (normally performed at an overhaul facility) |
|
Definition
| Shop Maintenance / Heavy Maintenance |
|
|
Term
| Adjust fuel control for maximum rated thrust |
|
Definition
|
|
Term
|
Definition
Fan and booster
High pressure compressor
Combustor
High pressure turbine
Low pressure turbine
Accessory drive |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| Airworthiness limitations |
|
|
Term
|
Definition
|
|
Term
| subsonic planes have what type of exhaust cone? |
|
Definition
|
|
Term
| Any type of maintenance that can be done while the engine is installed on the aircraft. |
|
Definition
|
|
Term
| Maintenance the requires the engine to be taken off the aircraft. (normally performed at an overhaul facility) |
|
Definition
| Shop Maintenance / Heavy Maintenance |
|
|
Term
| Adjust fuel control for maximum rated thrust |
|
Definition
|
|
Term
|
Definition
Fan and booster
High pressure compressor
Combustor
High pressure turbine
Low pressure turbine
Accessory drive |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| Airworthiness limitations |
|
|
Term
|
Definition
|
|
Term
| subsonic planes have what type of exhaust cone? |
|
Definition
|
|
Term
| Any type of maintenance that can be done while the engine is installed on the aircraft. |
|
Definition
|
|
Term
| Maintenance the requires the engine to be taken off the aircraft. (normally performed at an overhaul facility) |
|
Definition
| Shop Maintenance / Heavy Maintenance |
|
|
Term
| Adjust fuel control for maximum rated thrust |
|
Definition
|
|
Term
|
Definition
Fan and booster
High pressure compressor
Combustor
High pressure turbine
Low pressure turbine
Accessory drive |
|
|
Term
| A sever condition of chafing or fretting in which a transfer of metal from one part to another occurs is called... |
|
Definition
|
|
Term
| What must be done after the fuel control unit has been replaced on an aircraft gas turbine engine? |
|
Definition
|
|
Term
| Why is a cool-off period necessary prior to shutdown of a turbine engine? |
|
Definition
So the case does not shrink around blades
So cracking does not occur |
|
|
Term
| What is the purpose of an under-current relay in a starter-generator system? |
|
Definition
| Determines that a starter is spinning fast enough to shut itself off |
|
|
Term
| What is the primary advantage of pneumatic (air-turbine) starters over comparable electric starters for turbine engines? |
|
Definition
|
|
Term
| Describe the basic procedure for removing a turbine engine ignition system. |
|
Definition
Turn power off
Pull circuit breaker
remove leads
Wait to discharge
remove |
|
|
Term
| Describe the basic start procedure for a typical turbine engine. |
|
Definition
starter
ignition
add fuel last |
|
|
Term
| How is an APU cooled down prior to shutdown? |
|
Definition
| turn off bleed air loads and electricity |
|
|
Term
(T/F)
When an aircraft has an APU on board, an engine-mounted starter is required |
|
Definition
|
|
Term
(T/F)
Propeller RPM is the primary indication of thrust for a turboprop engine |
|
Definition
|
|
Term
(T/F)
EGT is a useful indication of thrust produced in a turbine engine |
|
Definition
False
(used for temperature) |
|
|
Term
| What are the factors that can cause a hung start? |
|
Definition
improper fuel control
problem with starter
starter doesn't crank long enough
battery dies |
|
|
