Engines
Of the 100% of air being introduced to the core of a turbojet engine, what percent is used for combustion?
25% to 35% depending of engine model/age.
The first section of a turbojet engine is the...
Air Inlet
If you do not wait the full six minutes for an ignitor to disipate its energy and disconnect it right after the turbine engine has been shut down, you will become.......
HISTORY!
How many spools does a turbofan engine generally have?
2
What is SOAP used for?
Oil sample taken from an engine and sent it to a analysis lab that can identify/predict component stresses/failure. (detecting metals from the components that are starting to surface in the oil sample. Example: high amounts of tin could reflect bearings are starting to wear beyond normal)
After you disconnect the exciter box on a PT6A-140 after only waiting 1 minute, where would you go to wash off your hands?
Heaven, at least for most of us. You done got killed!
List one component/system that one would possibly find attached to a battery bus bar?
Fire supression systems, interior lighting, basic radio
List one human factor in the Dirty Dozen
Lack of Communication, Complacency, Lack of Knowledge, Distraction, Lack of Teamwork, Fatigue, Lack of Resources, Pressure, Lack of Assertiveness, Stress, Lack of Awareness, Norms.
A Pratt and Whitney PT6A engine has what type of spool (shaft)?
Free-Turbine
"For every action there is an equal and opposite action" is Third Law of Motion devised by who?
Sir Isaac Newton
Who was always on time to class?
AM: True and Ethan
PM: Mr. Gill, Charlotte
Where does by-pass air come from?
The fan on a turbofan engine
What percentage of thrust is developed by the fan portion of a turbofan engine?
80%
Which country came up with the concept of gas turbine engines first?
England
1 compressor + 1 Shaft + 1 Turbine =
1 Spool
You just ate a bunch of ice cream cake. You then grabbed and dropped the $4,000 ignitor for the engine mounted on a Boeing 737 MAX that is loading up with 138 passengers. What should you do?
Throw it away or turn in to the parts department as a condemned part due to its unknown condition and get another one...after you wash your hands.
Part 145 refers to what? (In regard to the FAR's)
Repair Station.
What is ESD spelled out?
Electrostatic discharge
Everyone at the hangar completes a job but their process is not in alignment to the MM (Maintenance Manual). You ask a co-worker why. His answer is "We have always done it that way". What human factor is being broken in this scenario?
Norms
The gas generator turbine drives what component of the PT6A?
Compressor
An ATOM contains 3 components. What are they?
Proton, Neutron, Electron.
What days did Ms. Cassondra help us?
Thursdays
Low-Bypass engines are usually found on what type of aircraft?
Fighter Aircraft
A Turbine disc with the blades attached is called the....
Turbine Wheel
What country was the first to fly a gas turbine powered engine?
Germany
What 2 sources does an APU provide an aircraft?
High Pressure bleed air and electrical power.
What is a "FAST" box used for?
It automatically records all engine performance data.
List 3 systems that turbine bleed air provides (besides combustion)
Cabin pressurization, cabin heating, cabin cooling, de-icing, anti-icing, pneumatic starting, heating of brake assemblies for some aircraft (Beech 1900)
What is a bus bar?
Metallic bars used to transfer/centralize electrical power
What human factor is being broken when a mechanic is talking on his cell phone (betting on the Kentucky Derby) while working on an aircraft engine?
Distraction
What component on the PT6A prevents runway/taxiway rocks from entering the engine's intake and/or chunks of ice while in flight?
Inertia Seperator
Steel melts at what temperature?
1,100 Celcius
Who is Mr. Mike?
Lead UAA Technician
What type of gas turbine engine is used on helicopters?
Turboshaft
What section of a Turboshaft Engine is in-between the compressor and the turbine section
Combustion
What events in Titusville in Pennsyvania and at Spindletop Hill in East Texas saved the whale?
Discovery of oil
List 3 times when ignitors would be active (sparking)
upon start, wet weather, arrival, low level flying, landing, and when engaged in combat.
What does the term "Blade Creep" refer to?
Stretching of the turbine blades
Where would you find the Inlet Guide Vane Assembly on an JT8 Engine?
At the exit of the air inlet and just before the first stage of the compression section.
What is the biggest danger of ESD Damage (besides the actual failure of the component in question?
Damage can be unseen.
Name the Stress Safety Nets
(Hint: SLLA)
STOP,LOOK, LISTEN, ACT
What are the dimensions of the PT6A's intake screen (length and width in "inches")
1/4" by 1/4"
What identifying color is used on fuel lines?
Red
What color of eyes does Bella have?
Blue
The Cessna Caravan has what type of gas turbine engine?
PT6A Turboprop
Where in the gas turbine engine is the temperature the hottest (up to 2,000 Celcius)?
The first stage of the turbine just after the combustion chamber.
What country produces the Rotax engine used for aircraft?
Austria (the country that starts with an "A" and does not have kangaroos).
This component wastes fuel by dumping extra fuel into the exhaust section, consumes lots and lots of fuel, but gives the turbojet-powered aircraft a whole bunch more speed..
Afterburner
List one component in a "Hot Section"
Turbine Wheel, combustion chamber, ignitors, fuel nozzles
List one preventive action for having a drain mast on the bottom of the combustion chamber after shutdown?
Fire, overheat start, or varnishing/caking of residue on fuel nozzles, ignitors, and combustion chamber
What is another name for "pressure" in regard to electricity?
Volts
If you were not thinking and walked within 5 feet of a CFM56's intake while it is running, where could you find yourself next?
Spread all over the runway behind the engine.
In what country are the PT6A's manufactured?
Canada
What are turbine blades (in the turbine section...after the combustion section) coated with to protect against heat damage?
Ceramic
Where is the Collier Award located in the building?
By the auditorium
What is the primary advantage of a turboprop engine?
Short take-off and landing runways are possible
Where in a turbine engine is the highest pressure found?
Diffuser
What British Engineer designed and patented the first turbojet aircraft engine?
Frank Whittle
What is the job of a diffuser?
Slow down the velocity of the compressed air before it enters the combustion chamber.
What would a pilot report to you after a flight if it is known that the turbine compressor blades are worn down and leaving a bigger gap between the blades and the casing of the compression section?
Engine has loss of power/lacks power (not efficient)
What is an MRO?
Maintenance Repair Overhall
The two primary types of circuits used in electricity are:
Series and parallel.
What is the most important tool in your "toolbox"?
The grey matter that sits on top of your shoulders. It's sometimes called: Your brain, your noggin', your coconut, your cranium, your cerebral matter, your noodle.........
What type of compressor does a PT6A have?
Combo of both axial-flow and centrifugal
What identifying color is used on Hydraulic lines?
Yellow and Blue
Who is the best artist in the class?
AM: Mr. Johnson
PM: Lindsay
What is the number 1 reason for an engine not making it to its TBO?
Corrosion
Describe what the exhaust nozzle is.
The opening in the back of the engine (Where the core exhaust gasses are released into the atmosphere.
What do the following companies have in common:
GE, Pratt&Whitney, CFM International, Teledyne, Rolls-Royce?
All produce gas turbine engines used in aircraft.
Axial-Flow rotor blades are attached to the disc by what three methods?
Fir tree, dove tail, and bulb
If the TBO for a PT6A is 8,000 hours, at how many hours will a hot section inspection be performed?
At 4,000 hours
What is the compression ratio of one Axial-Flow Stage?
1:1.25
You just landed your old aircraft 5 minutes ago. The airplane was built in 1970. How many minutes should you wait before you have the maintenance crew move the aircraft?
15 minutes
If you decided not to wear personal protective equipment while painting an aircraft every day for one month straight, in an enclosed space to include not wearing a respirator, what meal will be fed to you for the rest of your life?
Cream of Wheat
How many fuel nozzles does a PT6A-114A have?
14
What formula is the primary reason a Turbofan produces so much thrust without consuming more fuel
F=MV
F=Force. (Thrust)
M=Mass of Air
V=Velocity (speed) fuel needed to increase V
Who has the best handwriting in class?
AM: Laci and Josie
PM: Lindsay and Charlotte
How many magnetos does the Rotax 916 IS have?
Zero
What are the 3 types of Turbine Blades?
Impulse, Reaction, and Impulse-Reaction
What is the Brayton Cycle?
The name given to the Thermodynamic cycle of a gas turbine engine to produce thrust.
What is the biggest concern if a Thrust Reverser is not operating properly?
Only half of the thrust reverser deploying (working)
How many aircraft engine fire bottles are installed on a typical commercial aircraft (do not include a fire bottle for an APU)?
2
Centrifugal compressors compress the air to what ratio?
8:1
List 3 habits you can utilize when inspecting/repairing/installing aircraft wiring
keep clean, keep organized, pick up FOD, take your time, remove dust bunnies, metal shavings, lightly tug or poke wire terminals to ensure wiring is properly dispose of this residue.
Per the FAA Personal Minimums Checklist, List 3 things you could do BEFORE performing a task
See checklist on your desk
What is the PT6A-15AG used for?
Agriculture
What document will tell you what spark plugs to use on your Lycoming Aircraft Engine?
Lycoming Service Instruction
In February, how does Kotzebue get: fuel, shoes, grandma, washing machine, car parts, oatmeal, books, fishing supplies, popcorn, hot dogs, clothing, medication, mail, flowers, spinach, pizza dough, eye glasses, teachers, school supplies, and kitchen sinks?
All by airplane!
The low-pressure compressor on a 3-Spooled engine would be identified by what instrument gauge in the aircraft's flighdeck?
N 1
What percentage of the air going into a turbojet is not combusted with fuel but used for cooling?
75%
What component of an aircraft stopped failing on a regular basis when smoking was no longer allowed on commercial aircraft?
Outflow valve (pressurization system).
Three types of combustion chambers for a turbine are:
Can, Annular, Can-Annular
Fuel nozzles are removed from the aircraft every 200 hours and sent to be inspected. What kind of maintenance is this?
Scheduled Maintenance
Define a "Cycle" (for Pratt and Whitney for example).
One engine start, wheel leave the ground, wheels touch the ground, engine shut down
You only had enough time on shift to install 10 of 20 screws on the leading edge of a horizontal stabilizer. What principle should you do/perform with that stabilizer to prevent the next shift from forgetting to completely install it.
Take it all the way off again (Rule: "All the way on or all the way off")
What should you do before attempting to open a cabin entry door of an airplane that has just landed?
Have the pilot open his/her window to ensure the aircraft isn't pressurized.
What determines if a PT6A is classified as a small, medium, or large PT6A?
Number of axial flow stages in the compression section.
Explain what a vortex dissipator is used for
Bleed air directed towards ground to break up vortex action that can be created by an engine running.
What President has his portrait in our classroom?
Honest Abe Lincoln
List 5 (of 7) reasons to lubricate your engine?
Reduce friction, cools, seals, cleans, cushions, serve as a hydraulic fluid, and protect against corrosion.
Three Part Question
1: where are the thermocouples located 2: What kind of circuit are they wired in regard to (series or parallel) 3: If one thermocouple fails, what will happen to your I.T.T.?
in turbine section, wired in parallel, and I.T.T. will be less accurate.
What US company developed the gas turbine engine for aircraft in the United States?
General Electric
We discussed 8 tips to PT6A Health. List 4.
Ask questions, Clean fuel nozzles, Borescope inspections, Engine washing(internal wash), Proper preservation, propeller balance, oil analysis, Cycle recording
The pneumatic starter is turning the engine to its duty cycle (Engaging the starter for a limited amount of time). The compressor is turning and fuel is being entered into the combustion Section; but the engine is not starting and in your headsets you cannot hear any ticking sounds. What is something that you can check for trouble shooting purposes?
Check the ignitors in the engine.
After the last stage of the compressor section is the Outlet Vane Assembly. What is the purpose of this assembly?
To straighten out (eliminate turbulence) the compressed air before entering the diffuser and combustion stage.
Electricity is a form of energy resulting from the existence of charged particles by 5 methods. List 2.
Friction, Chemical Reaction, Magnetic Fields, Photovoltaic
What measuring device could be used to measure the thickness of a human hair and to what accuracy?
Micrometer; 10,000th of an inch.
What does the "P", "T", and "6" indicate in the model "PT6A"?
Propeller, Turbine, 6th design of the PT6A model (A Means 2 Stage Compressor)
The JET ENGINE FAMILY includes 4 types. What are they?
Rocket Jet, Ram Jet, Pulse Jet, and Gas turbine-powered Jet
Who does Mr. Rogers appreciate the most in this class?
All of you; thank you!!!!! You put in a lot of work and invested in your future. It's been a great pleasure this year.
Now, go out and do good things!!!!
Respectfully, Mr. Rogers