Module 14 PropulsionFor full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk

1. From where is manifold pressure taken on a supercharged engine?a) Between the carburetor and the superchargerb) Between the supercharger and the throttlec) Between the carburetor and the induction ports

2. On a gas turbine engine, what is the fan driven by?a) HP turbineb) LP turbinec) IP turbine

3. What is an engine stage?a) One rotor plus one statorb) One IGV and one rotorc) One compressor rotor and one nozzle guide vane

4. The air data input to the FADEC fails. The result will bea) a lack of flight datab) uncorrected data from hard wired analogue sensors is utilizedc) the FADEC reverts to the failsafe mode

5. Torque measurement is taken from thea) free turbine shaftb) reduction gearboxc) prop shaft

6. A FADEC system consists ofa) HMU, sensors and an EECb) HMU, ADC and sensorsc) EEC, ADC and sensors

7. What power supply is required for a thermocouple system to work?a) Direct currentb) Alternating currentc) Neither of the above

8. In a 24 thermocouple system, one thermocouple goes open circuit. What error is detected at the indicator?a) Noneb) No indicationc) Gauge freezes at last known reading

9. In a thermocouple temperature sensing system, what is the purpose of the compensating resistor?a) To standardise the reading for different engine typesb) To correct for varying ambient temperatures at the cold junctionc) To correct for varying ambient temperatures at the hot junction

10. In a dive, with the throttles fixed, the EPR willa) increaseb) decreasec) not change

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How did you do'?Question 1The coned answer is c Read up on manifold pressure indication systems (The superchargerbills a red herring)Question 2 The correct answer is b Read up on basic gas turbine engine configurationsQuestion 3 The correct answer is a Read up on basic gas turbine engine configurationsQuestion 4 The correct answer is c Read up on FADECQuestion 5 The correct answer is b Read up on torque indication systemsQuestion 6 The correct answer is a Read up on FADECQuestion 7 The correct answer is c Read up on EGT indication systemsQuestion 8 The correct answer is a Read up on EGT indication systemsQuestion 9 The correct answer is b Read up on EGT indication systemsQuestion 10 The correct answer is c Read up ERR indicating systems

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1. How is the N1 and N2 measured on a triple spool engine?a) Pulse type speed probesb) Tachometer connected to the external gearboxc) Tachometer connected to the internal gearbox

2. A twin spool engine hasa) one turbine on one shaftb) two turbines on one shaftc) two turbines on two shafts

3. A free turbine aircraft engine is most likely to be used on aa) high bypass engineb) a direct coupled enginec) a helicopter engine

4. Propeller speed is measured froma) a slip ring pulse probeb) a tachometer on the LP turbine shaftc) a pulse probe at the engine side of the reduction gear

5. Propeller torque is analogous toa) engine RPMb) shaft horsepowerc) propeller RPM

6. How is power indicated on a fixed pitch propeller?a) RPM gaugeb) Torque gaugec) Horsepower gauge

7. What are the units of manifold pressure on a normally aspirated engine?a) PSIb) Inches of waterc) Inches of mercury

8. In a FADEC what is the result of Channel A failing to receive information from a sensor?a) Channel B will assume controlb) Channel A will take the information from channel Bc) Channel A will take the information from the backup sensor

9. A synchro pressure measuring system requiresa) alternating currentb) direct currentc) either ac or dc

10. A synchro pressure measuring system works on the principle of changes in pressure related to changes ina) frequencyb) voltagec) flux

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How did you do'?Question 1The coned answer is a Read up on basic gas turbine engine configurationsQuestion 2The coned answer is c Read up on basic gas turbine engine configurationsQuestion 3The co reel answer is c Read up on basic gas turbine engine configurations-a tree turbineallows Ice rotor to be stopped whilst the engine is runningQuestion 4The correct answer is a Read up on propeller speed indicating systemsQuestion 5The correct answer is b Read up on torque indicating systemsQuestion 6The correct answer is a Read up on fixed pitch propeller/engine indicating systemsQuestion 7The correct answer is c Read up on piston/propeller indicating systemsQuestion 8The correct answer is b Read up on FADECQuestion 9The correct answer is a Read up on synchro systems - see also module AQuestion 10The correct answer is c Read up on synchro systems - see also module AYour total score is 0Comment A trained chimp could do better! Best you give up now

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1. Pure jet engines usea) stagnation thermocouplesb) rapid responsec) variable resistance thermocouples

2. Modern oil pressure servo transmitters sensea) differential pressureb) absolute pressurec) HP oil pressure3. EGT thermocouples are usually made ofa) nickel and platinumb) chromel and platinumc) chromel and alumel

4. Thrust is generated in a turboprop system bya) moving a small mass of air quicklyb) moving a large mass of air quicklyc) moving a large mass of air slowly

5. Power is adjusted in a variable pitch turboprop aircraft bya) increasing RPMb) increasing fuel flowc) increasing pitch

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6. Thrust in a high bypass engine is measured by measuringa) N3 RPMb) fuel flowc) neither of the above, thrust is not indicated in flight

7. EPR is a ratio ofa) P1 to P4b) P1 to P fanc) P1 to P6

8. The majority of power in a free turbine engine is used toa) drive the gas generatorb) drive the free turbinec) expel gases through the exhaust

9. The total power in a turboprop engine is thea) SHPb) ESHPc) BHP

10. To measure oil temperature, which of the following would most likely be used?a) Resistance temperature measurementb) Thermocouple measurementc) Optical pyrometer

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Question 1The correct answer is a When you think of he difference in speeds of the jet efflux -on a pure jet and say, a turbofan engine, Then you willunderstand why a pure jet needs stagnation thermocouples lo slow the gas flow at the sensorQuestion 2The correct answer is a Read up on oil pressure sensorsQuestion 3The correct answer is c Read up on ThermocouplesQuestion 4The correct answer is c Read up on basic propulsion TheoryQuestion 5The correct answer is b Increasing fuel flow attempts lo increase RPM, but the governor resets the pitch to a higher setting-maintainingRPM but at a higher thrustQuestion 6The correct answer is c Thrust cannot be measured directly (not in flight anyway), so the fan speed is used as an 'indication' of thrust sinceit varies approximately linearly with thrustQuestion 7The correct answer is b ERR is the ratio of output pressure lo input pressures of a gas turbine engine Unless you know how many stagesThere are, you cannot say whether it is PI lo P4 or to P6 etc But a turbofan engine uses The ratio of pressures across The fanQuestion 8The correct answer is b About 85% of the power in the gas from the gas generator is used to drive The propeller (i.e. via The free turbine)Question 9The correct answer is b Equivalent Shaft Horsepower (ESHP) is The addition of Shaft Horsepower (The propeller shaft) and the thrust of theexhaust efflux (with a little conversion factor involved)Question 10The correct answer is a Read up on oil temperature measurementYour total score is 0Comment A trained chimp could do better ! Best you give up now l

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1. Pure jet engines usea) stagnation thermocouplesb) rapid responsec) variable resistance thermocouples

2. Modern oil pressure servo transmitters sensea) differential pressureb) absolute pressurec) HP oil pressure

3. E.G.T. thermocouples are usually made ofa) nickel and platinumb) chromel and platinumc) chromel and alumel

4. Thrust is generated in a turboprop system bya) moving a small mass of air quicklyb) moving a large mass of air quicklyc) moving a large mass of air slowly

5. Power is adjusted in a variable pitch turboprop aircraft bya) increasing RPMb) increasing fuel flowc) increasing pitch

6. Thrust in a high bypass engine is measured by measuringa) N3 RPMb) fuel flowc) neither of the above, thrust is not indicated in flight

7. EPR is a ratio ofa) P1 to P4b) P1 to P(fan)c) P1 to P6

8. The majority of power in a free turbine engine is used toa) drive the gas generatorb) drive the free turbinec) expel gases through the exhaust

9. The total power in a turboprop engine is thea) SHPb) ESHPc) BHP

10. To measure oil temperature, which of the following would most likely be used?a) Resistance temperature measurementb) Thermocouple measurementc) Optical pyrometer

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Question 1The correct answer is a When you think of he difference in speeds of the jet efflux -on a pure jet and say, a turbofan engine, Then you willunderstand why a pure jet needs stagnation thermocouples lo slow the gas flow at the sensorQuestion 2The correct answer is a Read up on oil pressure sensorsQuestion 3The correct answer is c Read up on ThermocouplesQuestion 4The correct answer is c Read up on basic propulsion TheoryQuestion 5The correct answer is b Increasing fuel flow attempts lo increase RPM, but the governor resets the pitch to a higher setting-maintainingRPM but at a higher thrustQuestion 6The correct answer is c Thrust cannot be measured directly (not in flight anyway), so the fan speed is used as an 'indication' of thrust sinceit varies approximately linearly with thrustQuestion 7The correct answer is b ERR is the ratio of output pressure lo input pressures of a gas turbine engine Unless you know how many stagesThere are, you cannot say whether it is P1 to P4 or to P6 etc But a turbofan engine uses The ratio of pressures across The fanQuestion 8The correct answer is b About 85% of the power in the gas from the gas generator is used to drive The propeller (i.e. via The free turbine)Question 9The correct answer is b Equivalent Shaft Horsepower (ESHP) is The addition of Shaft Horsepower (The propeller shaft) and the thrust of theexhaust efflux (with a little conversion factor involved)Question 10The correct answer is a Read up on oil temperature measurementYour total score is 0Comment A trained chimp could do better ! Best you give up now l

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P5

1. The principle of operation of a DC ratio meter isa) one coil moving in a uniform magnetic fieldb) two coils moving in a uniform magnetic fieldc) two coils moving in a non-uniform magnetic field

2. A thermocouple indicator is basically aa) mill voltmeterb) milliohmeterc) milliameter

3. If a FADEC loses its ADC input, in the short term it willa) go into soft redundancyb) go into hard redundancyc) go to limit protection mode

4. With an aircraft with a fixed pitch propeller, what indication has the pilot got of the output power?a) fuel flowb) oil pressurec) engine speed indicator

5. The primary purpose of an EEC isa) to change analogue inputs into digital format to provide glass cockpit information and reduce flight crewworkloadb) to change analogue inputs into digital format to reduce flight crew workload and provide maintenanceinformationc} to save fuel. reduce crew workload and reduce maintenance costs

6. If a tacho generator indicated in reverse, the probable cause isa) wrong input frequencyb) two phases cross connectedc) supply and transmitter cross connected

7. A sensing element goes open circuit in a ratio meter. What will be happen?a) Temperature indicates below ambientb) Full scale deflectionc) Hairspring takes indicator off scale

8. A thermocouple is constructed ofa) two dissimilar metals welded togetherb) two dissimilar metals with an air gap between themc) three dissimilar metals welded together

9. A thermocouple indication is taken from thea) hot junctionb) cold junctionc) difference between the hot junction and the cold junction

10. On a twin spool engine, the HP compressor is driven bya) ram air over the compressor

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b) early stages of the turbinec) later stages of the turbine

How did you do'?Question 1The correct answer is c E 1-1 J Pallet Aircraft Instruments and Integrated Systems page 31 G refersQuestion 2The correct answer is a E H J Pallet Aircraft Instruments and Integrated Systems page 323 refersQuestion 3The correct answer is a Soft redundancy is also known as the Alternate ModeQuestion 4The correct answer is c RPM or Manifold pressure are The only indications of power in a fixed pitch propeller/engineQuestion 5The correct answer is c The FADEC system provides greater operating and maintenance efficiencyQuestion 6The correct answer is b E H J Pallet Aircraft Instruments and Integrated Systems page 348 refers (ills also The sameAs with an AC motor)Question 7The correct answer is b E H J Pallet Aircraft Instruments and Integrated Systems page 318 refersQuestion 8The correct answer is a Commonly Alumel and Chromel in GTE applicationsQuestion 9The correct answer is b E H J Pallet Aircraft Instruments and Integrated Systems page 320 refersQuestion 10The correct answer is b The HP Compressor is always driven by the turbine nearest the combustion chamber

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1. In a multiple probe thermocouple system, what is the effect if one probe fails?a) No noticeable effectb) Reduction in temp readingc) Increase in temp reading

2. In a gas turbine if air is tapped from the H.P bleeda) EPR decreases and EGT increasesb) EPR stays constant and EGT decreasesc) EPR increases and EGT decreases

3. The vane on a vane type fuel flow measuring device becomes stuck. What safety backup is available for the enginefuel flow?a) A fuel bleed valveb) A bypass valvec) A differential pressure bypass valve

4. In a FADEC engine with a hydro mechanical fuel system, how is fuel flow controlled?a) By fuel pressureb) By electro-hydraulic servo valves (EHSVs)c) By oil hydraulics

5. In the HEIU the discharge resistorsa) allows sufficient voltage to be stored to provide relight facilities up to 55,000 ft.b) protects the unit from excessive voltages.c) allows the capacitors to discharge when the unit is switched off.

6. A modular constructed gas turbine engine means thata) its major assemblies can be removed and replacedb) all engines have a specific component layoutc) the engine is constructed by the vertical assembly technique

7. The purpose of a high bypass ducted fan engine is toa) improve efficiencyb) improve thrustc) reduce size

8. When using a test set to test an EGT thermocouple circuita) no compensation for ambient temperature is requiredb) only consider ambient temperature compensation if the ambient temperature is over2u°Cc) always compensate for ambient temperature

9. Where is EGT measured?a) In the combustion chamberb) Downstream of the combustion chamberc) Upstream of the combustion chamber

10. How does a boost gauge compensate for altitude changes?a) Spring sealed bellowsb) Two bellows against atmospheric pressurec) There is no compensation

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How did you do'?Question 1The correct answer is a All thermocouples are connected in parallel therefore the loss of one will not affect the output voltageQuestion 2The correct answer is a Jeppessen Gas Turbines page 8-7 refers to a shift in EPR Also note that a standard test of bleed valves openingis an increase of EGT is observedQuestion 3The correct answer is c EHJ Pallet Aircraft Instruments and Integrated Systems page 3G9 refersQuestion 4The correct answer is b. All FADEC engines have a hydro-mechanical unit within which are contained EHSVsQuestion 5The correct answer is c Rolls Royce The Jet Engine Page 129 refersQuestion 6The correct answer is a Rolls Royce The Jet Engine page 2G5 refersQuestion 7The correct answer is a Rolls Royce The Jet Engine page 17 refersQuestion 8The correct answer is a All EGT systems have automatic cold junction compensation See EHJ Pallet Aircraft Instruments and IntegratedSystems page 322Question 9The correct answer is b EGT is exhaust gas temperature therefore it is after the combustion systemQuestion 10The correct answer is a Read up on the manifold pressure gauge-Pallet Aircraft Instruments and Integrated Systems Pg 35G

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1. An EMF is produced by a thermocouple. This is senseda) at the hot junctionb) at the cold junctionc) between the hot and cold junctions

2. Supervisory EEC sends its output to thea) fuel valveb) HMU/FFGc) EGT thermocouple circuit

3. Ratiometer pointer movement is achieved bya) one coil providing a torque against a permanent magnetb) two opposing coils providing a torque in a varying magnetic fieldc) two opposing coils providing a torque in a permanent magnetic field

4. A fuel flow transmitter requires a motor or a synchronous motor to have aa) constant voltage within small tolerancesb) constant frequency within small tolerancesc) low EMF as it is immersed in fuel

5. A boost gauge measuresa) absolute pressure on the inlet portb) brake mean effective pressurec) gauge pressure at the injector

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6. On a thermocouple circuit on a non FADEC engine, what is the purpose of the ballast resistor?a) To compensate for ambient temperaturesb) To standardise both engine's EGT readingsc) To compensate for altitude

7. Boost pressure is measured ina) inches of Hgb) inches of waterc) PSI

8. Power is adjusted in a gas turbine engine bya) increasing airflow to the combustion chamberb) increasing air and fuel flowc) increasing fuel flow

9. The EPR reading is taken from a ratio ofa) jet pipe pressure to compressor inlet pressureb) compressor delivery pressure to compressor inlet pressurec) turbine inlet pressure to compressor delivery pressure

10. The basic gas turbine engine cycle isa) induction, compression, combustion, expansion, exhaustb) induction, compression, expansion, combustion, exhaustc) compression, combustion, induction, expansion, exhaust

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How did you do'?Question 1The coned answer is b Read up on The Thermocouple operationQuestion 2The coned answer is b Read up on EECQuestion 3The correct answer is c Read up on The ratio meterQuestion 4The correct answer is b Read up on fuel flow transmittersQuestion 5The correct answer is a Read up on The boost gaugeQuestion 6The correct answer is b Read up on The Thermocouple operationQuestion 7The correct answer is a CAPS leatlelAL/10-3 states that the boost pressure can be measured in in Hg orlbt/in2-leaflet EL/'M Para 13 2 quotes over boost figures in both Also Pallet aircraft Instruments &. Integrated Systems Pg355-357 mentions both Worth making a comment on the exam answer paper if you get this QuestionQuestion 8The correct answer is c Fuel flow is adjusted, which in turn increases The airflow and hence power outputQuestion 9The correct answer is a Read up on EPR indication systemsQuestion 10The correct answer is a Read up basic gas turbine engine Theory

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1. The high bypass ducta) drives a cabin air compressorb) provides engine coolingc) improves propulsive efficiency

2. If an engines fadec system loses air data permanently the pilot willa) select alternate pilot staticb) switch to alt on the relevant EECc) turn that EEC off

3. An EPR system reads slightly over 1, this would meana) the transmitter datum point has moved and needs replacingb) no action required this is normalc) the indicator needs re-calibrating back to 1

4. Manifold pressure is measureda) at inlet port above and below ambient conditionsb) at inlet port above and below standard atmosphere at sea levelc) at inlet port indicating boost pressure

5. A temperature indicating system incorporating a resistance bulb on a selected range has pointer movementa) proportional to bulb resistanceb) inversely proportional to bulb resistancec) resistance does not affect pointer movement

6. In a ducted fan engine, the fan is driven by thea) accessory gearboxb) turbinec) air passing over the compressor

7. In a FADEC system, active control switchover occursa) on shutdownb) when channels A and B are healthyc) on engine startup only

8. Gas turbines work on thea) otto cycleb) brayton cyclec) diesel cycle

9. Oil systems consists ofa) 2 systemsb) 3 systemsc) 4 systems

10. With the EEC in control the throttle levers are alwaysa) in the fully forward positionb) in the fully aft positionc) anywhere between the fully fwd and fully aft positions

How did you do'?

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Question 1The coned answer is c Read up on advantage of high bypass ratioQuestion 2The correct answer is a This is retelling lo The 7G7 CFG engine This is known as soft reversionary mode Engine uses last known T12 dataPressing The ALTN light switch puts it into hard reversionary mode where it will use ISA conditions (on both engines)Question 3The correct answer is b Engine Pressure Ratio (EPR) is The radio of turbine output pressure to compressor input pressure It is normal for itto be more than 1Question 4The correct answer is a When The engine is not running, The manifold pressure gauge will indicate ambient conditionsQuestion 5The correct answer is a As the temperature increases, The resistance increases-therefore 'directly proportional'Question 6The correct answer is b Read up on engine configurationsQuestion 7The correct answer is a on the CF6 FADEC, each startup uses an alternative channel But the switch over occurs on shutdown of theprevious run The reason for it is that a switch over on startup might interrupt the startup sequenceQuestion 8The correct answer is b Gas turbines work on the Brayton Cycle Piston engines work on The Otto cycleQuestion 9The correct answer is b An oil system has 3 sub-systems Suction, Pressure and ScavengeQuestion 10The correct answer is c The pilot sets the throttle to any position and The EEC controls to that commanded setting

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1. Turboprop thermocouple probes area) rapid responseb) stagnationc) surface mounted

2. Propelling nozzle providea) pressure thrustb) velocity thrustc) pressure and velocity thrust

3. How are the combustion chambers cooled?a) By l.p compressor airb) By h.p compressor airc) By fan pressure air

4. Fan blade speed is measured bya) phonic wheelb) drag cup and tachometerc) eddy currents

5. Fadecs operate bya) 2 controlling 1 operatingb) 1 controlling 1 operatingc) 2 units each capable of independent control

6. When a thermocouple fails, the temperature reading willa) over readb) under readc) stay the same

7. An aircraft flying at 500rnph would typically usea) turbojetb) turbofanc) turboprop

8. The inlet of a turbo fan isa) divergentb) convergentc) convergent-divergent

9. What is the pressure increase over one stage of a centrifugal compressor?a) 5:1b) 1.2:1c) 8:1

10. The bleed valve on a engine at start up isa) openb) closedc) modulating

How did you do'?

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For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.ukQuestion 1The correct answer is a Turboprop Thermocouples are rapid response This is because the gas flow is low speed in a turboprop exhaustQuestion 2The correct answer is c A propelling nozzle is used where gas flows are al sonic speed, and thus produce pressure thrust a swell asVelocity thrustQuestion 3The correct answer is b About 60% of the air exiting the compressor (HP compressor air) is used for cooling the combustion chamber anddilution of the flameQuestion 4The correct answer is a Since The tan does not normally drive The gearbox", a phonic wheel and an impulse pickup is used to measure thespeedQuestion 5The correct answer is c FADECs have 2 independent systems, each capable of controlling The engineQuestion 6The correct answer is c Thermocouples on a large engine EGT systems are wired in parallel and The indicators a voltmeter Therefore itone Thermocouple tails, The voltage across The indicator will not change However The reading will be less accurate due to a lowersampling of the temperatureQuestion 7The correct answer is a 500mph is supersonic Supersonic aircraft are powered by a turbojetQuestion 8The correct answer is a A turbofan engine has a divergent engine lo convert: airspeed into a pressure rise (ram pressure recovery)Question 9The correct answer is a centrifugal compressor has a pressure ratio of About 5:1 (per stage) An axial compressor has a pressure ratioof About 1.2:1 (per stage)Question 10The correct answer is a Choking of a compressor normally occurs on startup, Therefore The bleed valves are open at this time to preventchoking and subsequent surge

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1. EPR is measured between inlet anda) jet pipeb) cold and hot exhaustc) front of turbine

2. One stage of a turbine isa) n.g.v then turbine bladeb) turbine blade then n.g.vc) i.g.v then turbine blade

3. In a flow type fuel system, fuel shutoff is done bya) mechanical ball valveb) FCU torque motorc) l.p fuel cock

4. The fuel flow transmitter is downstream ofa) pr sovb) h.p pumpc) l.p pump

5. How is fuel flow varied in a variable displacement pressure type pump?a) Alter the cam plate angleb) Remote servo pressurec) Direct cable to cam plate

6. Advantage of flow type over pressure type isa) it has lower pressure so greater reliabilityb) it can take into account rpm, pressure (ambient) and e.g.t.c) has no need for fly weights and governors

7. When the full authority fuel control unit is changed, the rating pluga) stays with the engineb) stays with the FAFCc) is replaced every time

8. The EEC is powered and able to operate viaa) only a dedicated alternatorsb) the aircraft electrical systemc) The EEC is capable of being powered by both independently depending on conditions

9. The EEC usesa) ARINC 429 formatted datab) ARINC 629 formatted datac) uses neither ARINC 429 or 629 formatted data

10. The fuel metering unit has direct inputs viaa) only the EECb) the EEC and the fire control handlec) the EEC, fire control handle and the engine master switch

Question 1

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The correct answer is a EPR is the engine pressure ratio of engine inlet to jet pipe pressuresQuestion 2The correct answer is a One sage of a turbine includes one guide vane (stator) + turbine (rotor)Question 3The correct answer is a Fuel shut of is done with a valve incorporated with The throttleQuestion 4The correct answer is c Fuel Flow Transmitters downstream of the LP pump but before the HP pump and pressure regulating shut offvalve (pr sov) - Ret RR Jet Engine pg 113Question 5The correct answer is a Fuel flow is varied by altering The cam-plate angle (greater angle produces a greater stroke lo The pistons)However cam pi ale angle is controlled by The servo pressure, so Question is a little dubiousQuestion 6The correct answer is b The flow type fuel system can take into account rpm ambient pressure, EGT and other variables Ret RR JetEngine pg 103Question 7The correct answer is a The rating plug provides discrete engine information to the<BR>EEC Therefore The plug slays with The engineQuestion 8The correct answer is c 28VDC bus is required on start The dedicated generator <BR>lakes over as N2 or N3 increases (changeoveroccurs before 20%)Question 9The correct answer is a ARINC429 is The standard data bus for all Boeing /airbus<BR>engine systemsQuestion 10The correct answer is c The pilot must retain control of non normal and fire<BR>shutdowns

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P-11

1. The optimum turbine speed is defined asa) the most efficient speed of the turbineb) 100% rpm of the enginec) 95 % rpm of the engine

2. An increase in fuel flow through the impeller type fuel flow transmitter is measured bya) drum lags impellerb) impeller lags turbinec) decreasing angle between the two3. No power to EGT is indicated bya) yellow flag in front counterb) bug moves in the x directionc) bug moves in the y direction

4. Connection to a tachogeneratora) 3 phase starb) 3 phase deltac) 2 phase starFor full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk

5. A short circuit in a d.c ratio meter will givea) max scale readingb) zero scale readingc) min scale reading

6. An open circuit in a d.c ratio meter will givea) max scale readingb) zero scale readingc) min scale reading

7. A compressor shaft rotates ona) sintered bearingsb) ball and roller bearingsc) plain bearings

8. The EEC changes power settings bya) changing the throttle lever angleb) changing the fuel flow inputc) changing the airflow input

9. A torque pressure measuring indicator is fed bya) direct oil pressureb) differential pneumatic pressurec) servo operated

10. The tachogenerator output has:a) A fixed frequency

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b) A Variable frequencyc) A DC Current output

Question 1The correct answer is a Answer A is coned by elimination 100% is not a maximum and whilst 95% might be the most efficient (optimum)RPM for one engine type it will not before anotherQuestion 2The correct answer is b Pallet Aircraft Instruments 2nd edition page 334 refers The reference shows The impellor lagging the turbinegreater speed gives<BR> greater lag NB some references use The word rotor instead of impellorQuestion 3The correct answer is a Pallet Aircraft Instruments 2nd edition page 293 refersQuestion 4The correct answer is a Pallet Aircraft Instruments 2nd edition fig 10 13 el al refersQuestion 5The correct answer is c Pallet Instruments and Integrated systems Peters Page 318Ashorlwill remove all power from both windings andThe pointer will go to minimum scaleQuestion 6The correct answer is a CAAIPS (Old edition)AL10-Para11-10 states: An open circuit in the temperature sensing bulb or signal line will beindicated by max scale deflection Also see Pallet Instruments and Integrated systemsQuestion 7The correct answer is b Jeppessen Aircraft gas turbine Power plants Page 5-33Question 8The correct answer is b Jeppessen Aircraft gas turbine Power plants Page 7-17Question 9The correct answer is a Pallet Instruments and Integrated Systems Page 357Question 10The correct answer is b The faster the engine goes The faster The tacho generator goes

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1. On a fuel flow measuring device located on the enginea) no adjustments can be madeb) external adjustments can be made for maximum rate fuel flowc) external adjustments can be made for minimum rate fuel flow

2. Where is the hot junction of a EGT thermocouple system found?a) In the indicatorb) Upstream of the combustion chamberc) Downstream of the combustion chamber

3. The fan on a turbofan engine is turned bya) induction of the air across the fan into the compressorb) the turbine sectionc) the combustion chamber gases

4. When terminating connections for a EGT sensing systema) ensure that the pins and sockets are correctly crimped and brazedb) ensure that all connections are silver solderedc) ensure that the pins and sockets are of the same material as the leads

5. An EPR gauge indicates '1'. You shoulda) adjust the indicator back to zerob) replace the indicator, there is no adjustmentc) do nothing this is what it should read with the engine shut down.

6. A Gas Turbine's propulsion force is produced bya) reaction of the rearward moving gassesb) impingement of the gasses on the surrounding airc) induced airflow into the engine

7. In a single spool gas turbine engine the compressor rev/min isa) more than the turbine speedb) less than the turbine speedc) equal to the turbine speed

8. A tacho pointer is moved bya) drag cup couplingb) ac servo motorc) synchronous motor

9. In a twin spool enginea) the HP turbine drives both LP and HP compressorsb) the LP turbine drives the LP compressor and the HP turbine drives the HP compressorc) the HP turbine drives the LP compressor and the LP turbine drives the HP compressor

10. Relative permeability of fuel is also known asa) density of the fuelb) weight of the fuelc) dielectric constant of the fuel

Question 1

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The correct answer is a Pallet Aircraft Instruments and Integrated Systems Page 3G8-375 shows no on engine adjustmentQuestion 2The correct answer is c EGT stands for 'exhaust gas temperature 'Pallet Aircraft Instruments and Integrated Systems Page 320 referQuestion 3The correct answer is b See Rolls Royce The Jet Engine Page 5Question 4The correct answer is c Pallet Aircraft Instruments and Integrated Systems Page 32A refersQuestion 5The correct answer is c With the engine shutdown pressure al the intake and aft of the turbine is the sameQuestion 6The correct answer is a Newton’s Third Law- Every action has an equal and opposite reactionQuestion 7The correct answer is c See Rolls Royce The Jet Engine Page 5 In a single spool engine There is just a single speed for all rotatingassembliesQuestion 8The correct answer is a Pallet Aircraft Instruments and Integrated Systems Page 349 refersQuestion 9The correct answer is b See Rolls Royce The Jet Engine Page 5 The HP spool is either side of the combustion chamberQuestion 10The correct answer is c Pallet Aircraft Instruments and Integrated Systems Page 328 refers

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1. The cycle of a gas turbine engine isa) completed in one revolution of engine.b) completed in two revolution of the engine.c) continuous

2. Engines having two independent moving systems area) compound enginesb) twin spool enginesc) complex engines

3. Compression ratio of compressor of gas turbine Engine isa) outlet pressure to Inlet pressure.b) measured across all rotor stages of compressorc) mass of airflow to combustion.

4. Torque pressure indication to measure power output of an engine isa) used in all Gas Turbine engines.b) not used in Gas Turbine engines.c) only used when engine output pressure is used for torque not for thrust.For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk

5. Manifold pressure is measured ina) direct absolute pressure in Barsb) differential pressure in mill barsc) direct absolute pressure in inch of Hg

6. Typically a torque pressure indication system isa) differential pressure typeb) remote synchronous typec) direct Oil Pressure sensing type

7. A tachometer used to measure Rev/Min in turbine enginesa) develops its own power for the systemb) 28V dc is requiredc) 115V ac is required

8. Primary power for electronic engine controla) 115V ac essential bus.b) on side 115V ac bus bar supply.c) Permanent Magnet Alternator

9. Leads to measure thermocouple temperature area) calibrated for circuit in used and cannot be shortenedb) affected by Magnetic and electrical interferencec) insulated by heat legging device to reduce errors in the indication end

10. A thermocouple sensing system test set requiresa) a serviceable batteryb) No powerc) 24V dc

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Question 1The correct answer is c The Brayton cycle is a continuous cycle -A major advantage over the Otto Cycle (PistonEngine)Question 2The coned answer is b The 2 spools are known as LP Spool and HP spoolQuestion 3The correct answer is a Rolls Royce The Jet Engine Page 25 refersQuestion 4The correct answer is c Torque is used to measure power in turbo prop aircraftQuestion 5The correct answer is c EHJ Pallet Aircraft Instruments and Integrated Systems page 355Question 6The correct answer is c EHJ Pallet Aircraft Instruments and Integrated Systems page 357Question 7The correct answer is a It develops an alternating current proportional to the speed of the engineQuestion 8The correct answer is c Driven by The Engine's High Speed external Gearbox", it provides a discrete power supplyfor the engineQuestion 9The correct answer is a A&P Power plant Handbook EA-AC-65-12A page 494(4} refersQuestion 10The correct answer is a A&P Powerplant Handbook EA-AC-65-12A page 494 refers

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1. The HP compressor is powered bya) the first set of turbinesb) the last set of turbinesc) the intermediate compressor

2. Torque is measured in gas turbine enginesa) neverb) where there is a free turbine providing the powerc) on small pure jet engines3. What is the supply voltage to tacho generators?a) 28vdcb) 115vacc) It has no supply

4. A FADEC takes measurements of engine speed,a) temperature and pressureb) temperaturec) pressure

5. The fuel metering valve in the hydro mechanical unit of a FADEC system is operated bya) hydraulic servo pressureb) fuel servo pressurec) electrical servo

6. Boost pressure isa) atmospheric above ambientb) atmospheric below ambientc) the absolute of the manifold chamber

7. To check/test a temperature indicator you woulda) connect a decade box in place of the temperature sensing elementb) connect a decade box in series with the temperature sensing elementc) connect a decade box in parallel with the temperature sensing element

8. Calibration for a ratiometer type temperature indicator takes into accounta) the material of the coilsb) the material of the sensing elementc) the type of representation on the dial

9. Reverse thrust can only be selected when the throttle isa) 75% power position.b) open.c) at the idle stop

10. On a FADEC engine the EECa) has electronic control of the hydro-mechanical fuel control unit in all modesb) has electronic control of the hydro-mechanical fuel control in some modesc) has mechanical control of the hydro-mechanical fuel control system

Question 1The correct answer is a The HP Compressor spool has the shortest shaft

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Question 2The correct answer is b A Free turbine always powers a shaft or propellerQuestion 3The correct answer is c The Tacho generates its own voltageQuestion 4The correct answer is a All three are need to determine The fuel flow.. and the rate of accelerationQuestion 5The correct answer is b CFG course notes show that fuel is used to drive The FMVQuestion 6The correct answer is c EHJ Pallet Aircraft instruments and Integrated Systems page 356Question 7The correct answer is a By replacing The sensor with a known resistance you can simulate temperature increaseSee Question 8 belowQuestion 8The correct answer is b RTD's use platinum or nickel wire see EHJ Pallet Integrated Instruments page 409 table 3Question 9The correct answer is c A mechanical interlock on The Throttle slops The reverse thrust lever from moving it fwd thrustis anything but idleQuestion 10The correct answer is a The HMU is The interlace between The EEC and the fuel distribution system

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1. EPR is a measure ofa) exhaust pressure compared to compressor inlet pressureb) exhaust pressure compared to combustor pressurec) combustion pressure compared to compressor inlet pressure

2. What exactly does a thermocouple measure?a) The difference between the hot and cold junction.b) Hot junction temperature.c) Cold junction temperature.

3. In a temperature sensing ratio meter what determines the actual temperature?a) The material of the sensorb) The material of the sensing coilc) The material of the balancing coil

4. Torque is a useful measurea) on engines where a portion of thrust produces torqueb) on engines which only produce thrustc) on all engines

5. Boost pressure is a measure ofa) manifold pressureb) atmospheric pressure plus turbocharger inlet pressurec) atmospheric pressure less turbocharger inlet pressure

6. The test switch of a continuous loop fire detector gives aa) continuity checkb) bonding checkc) insulation check

7. What are the types of continuous fire detection system?a) Capacitive and resistiveb) Capacitivec) Inductive and capacitive

8. During normal running conditionsa) combustion is continuously supported by ignitionb) combustion is intermittently supported by ignitionc) combustion is self supporting

9. What indication does the pilot receive that thrust reversers have deployed ?a) A feeling of rapid decelerationb) An audible warningc) A sequence of lights

10. On a fixed pitch propeller single engine aircraft, what is indicated as a measure of power?a) Oil pressureb) Engine speedc) Cylinder head temperature

Question 1

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The correct answer is a EPR is used as a measure of thrustQuestion 2The correct answer is b The thermocouples are usually located within the turbine or jet pipe areaQuestion 3The correct answer is a Normally a resistive temperature device, it provides The resistance that changes The currentThrough The Wheatstone bridge arrangementQuestion 4The correct answer is a Torque sensing engines are turbo-prop or turbo-shaftQuestion 5The correct answer is b boost pressure is The term used when The manifold pressure is increased aboveatmospheric by a turbochargerQuestion 6The correct answer is a Jeppessen Gas Turbine Power plant Page 13-3 refersQuestion 7The correct answer is a Jeppessen Gas Turbine Power plant Page 13-3 refersQuestion 8The correct answer is c Once The engine reaches self sustaining RPM The starter and ignition cut outQuestion 9The correct answer is c Normally yellow for unlocked and green for deployedQuestion 10The correct answer is b the fastest the propeller goes The more power it produces

For full explanations of all these questions, and for many more new and up-to-date questions, with correct answers, full explanations, downloadable material and Tutorial Support, please visit http://www.club66pro.co.uk

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