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Fundamentals of GTE :
1. An example of a divergent duct is the-------jet pipe at the exit from the turbine
2.A turbo-prop engine derives its thrust from----reaction of the prop-wash
3.On an axial flow, dual compressor forward fan engine, the fan turns the same
speed as the--- low pressure turbine
4.Jet nozzle is locate---- at the exhaust
5.Axial flow turbojet engine highest gas pressure occurs at... compressor outlet
6.If LP shaft shears.... turbine runaway occurs
7.Density of gas.... weight/volume
8.Heat and mechanical energy are mutually convertible and 1 CHU isequal to....
1400ft/lbs
9.Turbojet engine gives....large acceleration to a small mass of air
10.ESHP.... shaft horsepower + exhaust efflux11.Engine most likely to have noise suppressor installed.... turbojet
12.In a dual axial flow or twin spool compressor system with a free power turbine,
Nf would indicate... free power turbine speed
13.The noise suppression system that increases the frequency of sound is termed....
multi-lobe type nozzle
14.The accessory gearbox of a high bypass engine is.... on the hp Compressor
housing
15.The purpose of a diffuser is to.... increase the static pressure of the air
16.A gas turbine engine comprises 3 main sections....turbine, compressor and
combustion
17.The hottest casing is the ---HPT
18. Which has the better combination....
Centrifugal compressor, axial flow turbine, can type combustion chamber
19. Statement that is true for a high bypass ratio turbofan....
the compressor assembly is larger and combustion chamber smaller than their turbojet
Equivalent20.A waisted drive shaft is primarily to....provide a fuse if the driven component is overloaded
21.A turbojet engine is smoother running that a piston engine because....
it has no reciprocating parts
22. Section that provides proper mixing of fuel and efficient burning of the
gasses.....
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Combustion section only
23.Unit generally used to measure aircraft noise....
Effective perceived noise decibels (EPNdB)
24. Core engine or gas generator made up of following components....
Turbine, combustion chamber, compressor25. There is no peak pressure in a jet engine because of....
Continuous flow of air
26.A nozzle is choked when the gas flow through it is....
sonic
27.A high bypass engine results in....
overall slower airflow and greater propulsive efficiency
28.In a free turbine....
There is no mechanical connection with the compressor
29.The advantage of a geared, fan type, dual spool engine is....
a geared fan does not need a separate turbine to have a different speed from the compressor
and the compressor is not limited to the fan speed
30.If a volume of a mass of air is 546 cubic feet at 273K, at 273K it will be....
2 cubic feet greater
31.In a pure jet engine, the rate of pressure rise is greatest atthe....
compressor stage
32. Ram effect is....
Conversion of kinetic energy to pressure energy at the face of the compressor33. Example of a divergent duct....
jet pipe at the exit from the exhaust
34.Part of the jet engine has the most potential energy
....just before the combustion chamber
Engine performance:
1. At constant RPM, the pressure ratio of the compressor and the temprise
across the compressor....Remains constant irrespective of height
2. Method of comparing engine efficiencies is by comparing....
Specific fuel consumption
3. Engine section tha t will produce the most amount of discrete noise....
Turbine
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4. Gas pressure is greatest at the....
Compressor outlet
5. Thrust rating on a FADEC engine can be changed by....
Changing the engine rating plug
6. The RP M for max po we r wo ul d be . . . . lower on a colder day7.As the speed of an aircraft increases, the momentum thrust of an engine
will....
decrease (momentum thrust is a product of the difference between aircraft speed and the jet
efflux speed)
8.Specific fuel consumption for a turbo prop engine....
decreases with increase in aircraft speed
9.Reduction in engine efficiency can be caused by....
ice formation on air intake
10.Power is adjusted in a gas turbine engine by....
increasing air and fuel flow
11.Ram recovery is the point at which intake....
total pressure equals ambient pressure
12.The point of maximum velocity in the engine is in the....
exhaust exit nozzle
13.Through turbine rotor blades, the pressure....
decreases, temp and velocity decreases
14.To maintain the selected RPM of a gas turbine at altitude....the pilot will have to throttle back
15.Ultimate limiting factor of turbine engine operation....
turbine inlet temp
16.Ram effect due to aircraft forward speed will cause the thrust of theengine to....
remain constant
17.Increasing ram effect with increased speed....
increases thrust dueto increased maximum airflow18.Temperature of the mass airflow through a gas turbineengine....
increases from the inlet, thru the compressor and thediffuser into the burner and
decreases thru the turbine intothe exhaust
19.Most engines try to keep a uniform...
flame temp
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20.If the throttle position remains constant...
with increasing OAT, RPMand TGT will increase
21.What happens to thrust as an aircraft climbs with a fixed throttleposition....
thrust decreases
22.Compressor type that gives the greatest advantage for both startingflexibilityand improved high altitude performance....
split spool, axialflow
23.Some turbo prop and turbojet engines are equipped with two spool orsplit
compressors. When these engines are operated at high altitudes,the....
low pressure rotor will increase in speed as thecompressor load decreases in the lower density
air
24.Effect of high atmospheric humidity have on the operation of a jetengine....
has little or no effect
25.The engine rating plug is.....
permanently connected to the enginecasing
26.Ram recovery is a measure of....
intake efficiency
27.The speed of the low pressure compressor increases as the inlet tempbecomes
colder because...
the fuel controller senses thedecreased T2 and schedules an increase in fuel flow
tomaintain the proper fuel air ratio with the denser air
28.Flat rated thrust is defined as....the thrust at the ambient temperature point above which thrust drops below 100%
29.With an increase in forward speed, the engine thrust...
decreases slightly but recover due to ram effect
30.The propulsive efficiency is...
high with a low mass flow acceleration
31.At constant RPM, the pressure ratio of the compressor and the temprise across the
compressor....
remains constant irrespective of height32. Across the turbines, there is.... a general temp drop
33. Hottest component in a gas turbine engine is the.... nozzle guide vanes
34.Statement that is true regarding jet engines...
.at higher enginespeeds, thrust increases rapidly with small increases in RPM
35.Turbine inlet temp is approx....
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850-1700 degrees celcius
36.What effect does high atmospheric humidity have on the operation of a jet
engine....
has little or no effect
37.Ram pressure recovery will generally take effect at aircraft speeds of....Mach 0.1-0.2
38.Factor that limits EGT is the....
turbine
39. The highest heat to metal contact in a jet engine is....
the turbine inlet guide vanes
40.To ensure an engine maintains self-sustaining speed....
idle increases with density decrease
41.The main factor considered when designing an engine is....
maximum turbine temp
Inlet:
1. In takes a re des igned to
decelerate the free air stream flow
2.The inlet door of a variable geometry intake at supersonic speeds will be
closed
3.The inlet door of a variable geometry intake is open atsubsonic speeds
4.A variable geometry intake at subsonic speeds
throat area is increased
5. The purpose of a bell mouth compressor inlet is to maximize the
aerodynamic efficiency of the inlet
6. What is true for a bell mouth intake (is a convergent duct) velocity
increases and pressure decreases7. An increase in the Ram Ratio of an intake will increase the temp of the
air
8 . In take momentum drag causes
a decrease in thrust at low airspeeds
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9.In a variable geometry intake, the velocity of the air on the engine
compressor face is controlled by Shock-wave pattern, ramp and spill doors
10. In a subsonic multi-engine aircraft, a normal inlet duct will increase in size
front to rear along the length of the duct
11. With an electrical ice protection system, the heating elements operate partcontinuous-part intermittent
12.A bell mouth compressor inlet is used on helicopters
13.Variable Ramp Intakes restrict airflow by creating shock-waves in the intake
14. The most efficient engine intake on subsonic or low supersonic aircraft is
pitot.
15.A turboprop engine inlet anti-ice system operates
.continuously
16.An aircraft flying at
Supersonic speed, to reduce the air velocity at the compressor, the variable
intake.
throat area is decreased
17.The cycling speed of the electrical de-icing mat.
is affected byweather conditions
18.Ram Ratio in regard to air intakes is the relationshipbetween.
ambient pressure and compressor inlet pressure
19.Vortex dissipaters prevent engine FOD by
a stream of enginebleed air blown toward the ground ahead of the engine20.Pitot type intakes are used in
subsonic aircraft
21.As an aircraft approaches the transonic range, the aerodynamicefficiency of a
pitot type intake.
decreases due to the shock wave
22.Electrical de-icing operates.
continuously and intermittently
23.A well designed intake will take advantage of forward speed byconverting kinetic energy into pressure energy
24.The variable inlet guide vanes are operated.
by fuel pressure
25.If an inlet is choked then the velocity.
decreases and pressureincreases
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Compressors:
1.In a turbine engine with a dual spool compressor, the low
speedcompressor.
seeks its own best operating speed
2.In flight, failure of compressor bleed valve (jammed open) will makeengine run
at.
lower RPM than normal
3.In a dual compressor, the low pressure compressor (LPC) speed tendsto change
with.
the CIT of LPC
4.On which blade type may a mid-span shroud most likely beused.
long, narrow chord type blades5.Advantage of centrifugal flow compressor is its high.
pressure riseper stage
6.2 types of centrifugal compressor impellers are.
single entry anddouble entry
7.Pressure rise across a single spool axial flow compressor is in the orderof.
up to 15:1
8.During low RPM range, variable intake guide vanes and bleed
valvesarea at.
maximum swirl position and bleed valves open
9.Advantage of a multi-spool compressor is.
quicker accelerationand better control of stall characteristics
10.Engine bleed at high speed is
.sometimes open
11.Centrifugal compressor produces a compression ratio.
lower thanthe axial flow compresso
12.Why in an axial flow compressor is the cross sectional area of thecompressorair duct reduced at each stage.
to maintain thevelocity of the air under rising pressure
13.On a high bypass ratio engine, what medium operates the VBV.
fuelpressure
14.Abradable lining around the fan is to.
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strengthen the EPR value
15.Compressor surge is caused by.
over fuelling
16.Purpose of stator blades in the compressor section.
control thedirection of the airflow17.Inlet guide vanes are fitted to.
control the angle of airflow intothe compressor
18.Type of combustion chamber is most suited for centrifugalcompressors.
multiple-can type
19.Surge margin of an axial flow compressors.
the margin betweenthe compressor working line and the surge line
20.A bleed valve.
relieves compressor choking at low RPM
21.What is the function of the stator vane assembly at the discharge endof a typical
axial flow compressor.
to straighten airflow toeliminate turbulence
22.Which of the following can cause fan blade shingling in a turbofanengine.
large, rapid throttle movements and FOD
23.Advantage of an axial flow over a centrifugal flow gas turbineengine.
high peak efficiencies
24.What is the profile of a compressor blade.
a cut out that reducesblade tip thickness25.How does a dual axial flow compressor improve the efficiency of aturbojet
engine.
higher compression ratios can be obtained
26.The stator vanes in an axial-flow compressor.
convert velocityenergy into pressure energy
27.A function of a cascade vanes in a turbojet engine compressorsection.
to remove air swirl before the combustion chamber
28.Stall will occur in the high pressure stages of an axial flow
compressorbecause.air mass flow is reduced when the compressor isturning at high speed
29.Purpose of bleed valve, located at the beginning stages of thecompressor is to.
vent some of the air overboard to prevent acompressor stall
30.No damage is permissible on.
a shroud-fillet area
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31.Air thru the compressor, before entering the combustion chamberpasses.
thru divergent passage to increase the pressure
32.Purpose of rotating guide vanes on a centrifugal compressor isto.
direct the air smoothly into the impeller
33.Variable inlet guide vanes prevent.compressor stalling
34.The diffuser after the compressor, before the combustionchamber.
decreases velocity, pressure increases
35.Cascade vanes in the intake of a centrifugal compressor areto.
provide a pre-swirl to incoming air
36.A function of the cascade vane in a turbojet engine compressorsection.
to remove air swirl before the combustion chamber
37.Purpose of the diffuser vanes of a centrifugal compressor serve.
toconvert kinetic energy into pressure energy
38.An axial flow compressor surges when.
all stages are stalled
39.Phase of engine operation will bleed valves be fully open.
rapiddeceleration
40.Compressor stage.
one rotor plus one stator
41.Tip speed of a centrifugal compressor can reach.
Mach 1.2 / 1.342.An axial flow compressor compresses the air by.
diffusion
43.Cascade Effect is related to.
axial flow compressors
44.What is the normal pressure rise across each compressor stage of anaxial flow
compressor.
1.2:1
45.Diffuser vanes are used in jet engines to convert.
kinetic energyinto potential energy thru divergence46.Stator vanes in an axial-flow compressor.
convert velocity energyinto pressure energy
47.A compressor stage stalls when.
smooth airflow is disrupted
48.Purpose of a counter-rotating spool in some dual or triple-spoolcompressors is.
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dampening gyroscopic effects
49.The optimum air speed for entrance into the compressor isapprox.
Mach 0.4
50.The effect of different stages in an axial flow compressor is.
tomultiply the pressure by each succeeding stage51.An axial compressor case annulus is.
convergent
52.If the RPM of an axial flow compressor remains constant, the angle of attack of
the rotor blades can be changed by.
changing thevelocity of the airflow
53.Compressor stalls may be eliminated by using which of the followingsystems.
compressor bleed-air system and variable vanesystem
54.The fan speed of a twin spool axial compressor engine is the same asthe.
low pressure compressor
55.The vanes of a diffuser in a centrifugal compressor.
are tangentialto the impeller
56.Primary factor which controls the pressure ratio of an axial flowcompressor.
number of stages in compressor
57.The compression ratio of an axial flow compressor is a functionof.
number of compressor stages
58.What units in a gas turbine engine aid in guiding the airflow during lowthrust
engine operations.inlet guide vanes
59.For any given power lever setting, the speed of the high pressurecompressor is
held constant by.
the fuel control governor
60.Compressor stall is caused by.
a high angle of attack airflow thruthe first stages of compression
61.Energy changes that take place in the impeller of a centrifugalcompressor are.
pressure increase, velocity increase, tempincrease
62.Compressor blades reduce in length.
from LP to HP section tomaintain uniform velocity in compressor
63.A bypass engine LP compressor.
supplies more air than isrequired for combustion
64.Severe rubbing of turbine engine compressor blades will usuallycause.
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galling
65.Stagger angle is used on the compressor blades to.
maintain exitvelocity of airflow at the same value along blade length
66.An axial compressor case annulus is.
convergent (all axial flowcompressor case annulus are convergent to maintainaconstant axial velocity thru the compressor)
67.In an axial flow compressor is the cross sectional area of thecompressor air duct
reduced at each stage.
to maintain thevelocity of the air under rising pressure
68.The root of the compressor blades are loosely fitted to the compressordisks. This
is because.
it aids easy blade assembly and itprovides a vibration damping effect
Combustion section:
1.A tubo-annular gas turbine combustion system consists of.
a numberof flame tubes in an annular air casing
2 .Di lu t ion a i r i s p laced.
in the dilution zone of the combustionchamber after the primary zone
3.Why is i t necessary to have a combust ion chamber drain.to
allowunburnt fuel to drain away.
to prevent initial over-fuelling onstart-up or hot start
4 .A torodia l vor tex i s.a region in the combustion chamber of lowvelocity recirculation
5.The main purpose of combustion is to
.increase gas velocity
6.What is a cannular combustion system.
a set of flame tubes,enclosed in a common air casing
7. Another name for a cannular combustion chamber is.
can-annular
8 .Duplex burners have.
two calibrated outletsone for low speed,second for high speed9.Combustion sections used in turbine engines.
multiple can, annularand can annular
10.Component that creates a vortex in a gas turbine flame tube.
swirlvanes
11.In a turbo prop engine, combustion takes place atconstant.
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pressure
12.Air thru the combustion chamber retains a constant.
pressure
13.Percentage mass airflow taken by flame tube snout.
18%14.Percentage mass airflow which bypasses the flame tube snout.
82%
15.A combustion chamber has a.
divergent inlet, convergent outlet
16.The purpose of the nose or snout in a combustion chamber.
to act asa diffuser to slow the airflow down
17.Combustion chamber drain valve closed.
by combustion chambergas pressure
18.Combustor air that is not used to support combustion.
will film coolthe liner and dilute combustion chamber exit temp
19.Air used for combustion is.
primary
20.Overall air/fuel ration of a combustion chamber can varybetween.
45:1 and 130:1
21.Air passing thru the combustion section of a jet engine is.
most usedfor cooling
22.In the combustion chamber.static pressure decreases slightyand volume increases
23.Flame stabilization in a combustion chamber is achieved by.
theairflow pattern
24.At high rotational speed at sea level, a duple burner would be passingfuel via
the.
primary and the main nozzle
25.When light-up takes place
.interconnectors spread the heat toadjacent flame tubes
26.Combustion liner walls cooled in a gas turbine engine.by secondaryair flowing thru the combustion chamber
27.In an annular combustor (thru flow).
it requires less cooling airdue to its minimal surface area
28.Fuel entering the combustion chamber from an atomizer spray nozzleenters as.
a fuel/air mixture
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29.A duplex burner uses.
small burner at low rpm and both burnersat high rpm
30.Component that creates a vortex in a gas turbine flame tube.
swirlvanes
31.Hot spots in the combustion section of a turbojet engine are possiblydue to.malfunctioning fuel nozzles
32.A shroud placed around fuel nozzles.
prevents carbon build up
33.In which type of turbine engine combustion chamber is the case andliner
removed and installed as one unit during routinemaintenance.
annular
34.Purpose of swirl vanes in the combustion chamber is to produce.
gasre-circulation
8.As hot gasses flow thru an impulse turbine blading, thevelocity....remains
constant9.An impulse turbine blade arrangement forms....constant passage10.A
slow constant growth in a turbine blade is known as....secondarycreep11.The
passage between adjacent nozzle guide vanes forms....convergentduct12.Turbine
engine components are never manufactured by....gas welding13.Impulse turbine
blades run cooler than reaction bladesbecause....temperature drop across NGV is
greater14.Fir tree turbine blade attachment locates the blade....allowsslightmovement15.Stress rupture cracks usually appear on turbine blades
at....across heleading or trailing edge at the right angle to the edge16.What is meant
by a shrouded turbine....the turbine blades are shapedso that their ends forma a band or
shroud17.hot streaking is caused by....a partially clogged fuel nozzle18.Creep of
turbine blades is....due to thermal and centrifugal forces19.Nozzle guide vanes are
fitted to....increase velocity of gas flow20.Temperature thru the turbine stages
generally....decreases21.As the hot gasses flow thru an impulse turbine blading,
thevelocity....remains constant22.Nozzle guide vane bow is an indication
of....engine overheat23.Turbine nozzle diaphragms located on the upstream side ofeachturbine wheel are used....to increase the velocity of the heated gassesflowing
past this point24.Alloys used for gas turbine nozzles are....inconel, nimonic and
GMR-23525.Turbine disk growth is due to.... a permanent change in disk
diameter26.Dirt particles in the air going into the compressor of a turbine
enginewill form a coating on all except the....turbine blades
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27.How is a radial turbine driven....by change of momentum and angle
of airflow28.The forces driving a turbine round are due to....impulse and reaction
EXHAUST
1.The jet pipe of a gas turbine engine.
protects the airframe fromheat damage2.Lobe type exhaust noise suppressors are made from
heat resistantalloy
3 .A supersonic duct i s
convergent then divergent along its length
4.When should thrust reversers be used
low RPM and low forwardspeed
5.The purpose of a propelling nozzle (convergence) is to
increase thevelocity of the air and increase thrust
6.If the exit area of the nozzle is too large, the effect is.
exit velocitylower causing loss of thrust
7.As air flows out at the outflow of a choked nozzle.
velocityincreases and pressure decreases (convergent duct-exhaust)
8.Exhaust noise can be reduced by.
increasing the mixing rate
9.A convergent exhaust nozzle produces mainly.
momentum thrust
10.To have minimum friction in the jet pipe, it should be.long andsmall diameter
11.A convergent-divergent nozzle.
makes maximum use of pressurethrust
12.The purpose of a propelling nozzle of a gas turbine engine isdesigned.
to increase the velocity and decrease the pressureof the gas stream leaving the
nozzle (increase thrust)
13.The exhaust section is designed to.
impart a high exit velocity tothe exhaust gasses
14.The struts on the exhaust cone.supports the exhaust cone andstraighten the gas airflow
15.On front fan engines, to obtain thrust reversal
cold stream isreversed
16.Reverse thrust can only be selected when the throttle is.
closed
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17.Thrust reversers utilizing pneumatics actuating system receivesoperating pressure
from.
engine bleed air system
18.An exhaust cone placed aft of the turbine in a jet engine will cause thepressure
in the first part of the exhaust duct to.increase andvelocity to decrease
19.The function of the exhaust cone assy of a turbine engine isto.
straighten and collect the exhaust gasses into a solidexhaust jet
20.Hot spots on the tail cone of a turbine engine are possible indicators of a
malfunctioning fuel nozzle or.
a faulty combustion chamber
21.A nozzle is choked when the engine inlet airflow is.
subsonic andsupersonic
22.What is the proper operating sequence of using thrustreversers..
retard thrust levers to grd idle, select reversethrust, then advance power levers as
required, and then retardthrust reverser levers to grd idle
23.Noise from a jet wake when untreated by suppression is
low freq,high decibel
24.A choked nozzle
increases thrust
bearing and seals :
1.A carbon seal has which type of sealing arrangement....full contactwith race
2 .Some labyr in th sea ls . . .
control the outflow of air at the turbine(can be air seals or oil seals)
3.An abradable lining in the fan case...
provides acoustic medium
4.Why are oil seals pressurized...
to ensure minimum oil loss
5.The highest turbine bearing temp takes place...
at shut-down6.Seals on gas turbine engine restrict leakage of oil by...
air pressure
7.What is the purpose of pressure balance seal...
to ensure thelocation bearing is adequately loaded throughout the enginethrust range
8.The function of labyrinth seals is to create...
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a restricted leakage of air between fixed and rotating components
9.If ball or roller bearings found with magnetism...
degaussed beforeuse
10.Main bearing oil seals used with turbine engines areusually...
labyrinth and/or carbon11.The bearings of a compressor rotor are usually.
ball and roller
12.In a jet engine, the rotating assembly oil seals are maintained oil tightby means
of...
air pressure
13.Which of the following is true about ball and roller bearings...
a ballbearing has less friction than any other type
Lubricants and fuel:
1.Advantage of mineral base lube over vegetable based lube
chemicalstability
2.Desirable characteristics of turbine engine oil
high flash point
3 .Reid Vapour pressure
38 degrees Celsius
4.Factors that determines the proper grade of oil to use in a
particularengine
operating speeds of bearings5.High tooth pressures and high rubbing velocit ies in spur type
gearsrequire the use of
an EP lubricant
6.The result of operating an engine in extremely high temp usinglubricant
meant for much lower temp
oil pressure will be lowerthan normal
7.Upon what quality or characteristics of a lubricating oil is its viscosityindex
based
its rate of change in viscosity with temp change8.The specific gravity of fuel affects
aircraft range
9.In addition to lubricating, engine oil
cools, seals, preventscorrosion and cushions shock loads
10.Calorific value is the
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amount of heat or energy in 1 pound of fuel
11.Compared to reciprocating engine oils, the types of oils used in
turbineengines
have less tendency to produce lacquer or coke
12.DERD 2494kerosene
13.Types of water present in aviation fuel are
free and entrained bothharmful
14.Ignition of fuel depends on
both volatility and atomisation
LUBRICATION SYSTEM (10):
1.The purpose of a pressure filter in a lubrication system is to.
protectthe oil jets
2.In a jet engine which uses a fuel oil heat exchanger, the oil temp
iscontrolled by a thermostatic valve that regulates the flow of.
oil thruthe heat exchanger
3.The oil dampened main bearing utilized in some turbine engines isused to.
provide an oil film between the outer race and thebearing housing in order to
reduce vibration tendencies in therotor system, and to allow for slight
misalignment
4.Oil pressure and scavenge pumps are usually.
spur gear pumps5.What wil l happen to the return oil if the oil l ine between the
scavengerpump and the oil cooler separates
.the return oil will be pumpedoverboard
6 .Oi l p ressure in the cooler i s.
higher than the fuel pressure
7.The possible cause when a turbine engine indicates no change inpower
settings parameters, but oil temp is high.
engine mainbearing distress
8.At cruise RPM, some oil will flow thru the relief valve of a geartypeengine oil pump. This is normal as the relief valve is set at a pressurewhich is
.lower than the pressure pump capabilities
9.The possible combined output from all the scavenge pumps in
alubrication system will be.
greater than the pressure pumpoutput
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10.Last chance filters in a lubrication system are servicedduring.
engine overhaul
11.What is the primary purpose of the hopper located in the oil supplytank of some
dry sump engine installations
.to reduce the timerequired to warm the oil to operating temp12.Primary purpose of the oil breather pressurization system that is usedon turbine
engines
.provides a proper oil spray pattern from themain bearing oil jets
13.A thread type oil seal in a lubrication system.
has a thread on astationary portion to prevent fluid leaks
14.What would be the probable result if the oil system pressure relief valve should
stick in the open position on a turbineengine.
insufficient lubrication
15.What determines the minimum particle size which will be excluded orfiltered
by a cuno type filter.
the spacer thickness
16.In order to relieve excessive pump pressure in an engines internal oilsystem,
most engines are equipped with a.
relief valve
17.Manufacturers normally require turbine engine oil servicing within ashort time
after engine shut down primarily to.prevent overservicing
18.When rotating, the gerotor type oil pump.
draws oil into the pumpand carries it round between the gear teeth and idler
19.What filters are used to protect oil pressure spray jets.
in-linethread filters
20.Low oil pressure can be detrimental to the internal engine components.however
high oil pressure
.should be limited to the enginemanufacturers recommendation
21.What is the purpose of the last chance filters.to prevent damageto the oil spray nozzle
22.A turbine engine dry sump lubrication system of the self contained,high pressure
design.
consists of pressure, breather andscavenge subsystems
23.A full flow oil system has.
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a variable oil pressure dependant uponthrottle setting
24.When rotating, the gear type oil pump
.draws oil into the pumpand carries it round between the gear teeth and casing
25.What is the primary purpose of the oil breather pressurization systemthat is used
on turbine engines.provides a proper oil spraypattern from the main bearing oil jets
26.The air-cooled-oil-cooler has an anti-surge valve in order to.
protectthe cooler
27.A vane type oil pump output is controlled by.
outlet pressureagainst spring pressure
28.Possible failure related ferrous metal particles in turbine engine oilcauses an
electrical indicating type magnetic chip detector to indicatetheir presence by.
bridging the gap between the detectorcentre (positive) electrode and the ground electrode
29.The teeth of the gears in the accessory section of an engine normallylubricated
by.
31.A jet engine gear box breather is prevented from leaking oil toatmosphere by
the action of
.impeller and centrifugal force
32.Type of oil pumps most commonly used on turbine enginesare.
positive displacement
33.A scavenge filter is incorporated in a gas turbine lubrication systemto
.protect the pressure pump34.The identification of a lubrication fluid line is the wordlubrication.
followed by squares
35.After making a welded repair to a pressurized type turbine engine oiltank, the
tank should be pressure checked to.
not less than 5psiplus the maximum operating pressure of the tank
36.Oil pressure in the cooler is.
higher than the fuel pressure
37.Typical operating pressure of an oil pump in a a gas turbine lubricationsystem.
30psi38.What is the cause of high oil temp.
a blocked pressure filter
39.Oil system generally used on most modern turboprop engines is.
drysump type
40.A spur gear pump operating in a lubrication system promotes.
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highflow at low pressure
41.The possible combined output from all the scavenge pumps in alubrication
system will be.
greater than the pressure pumpoutput
42.Sump pressure is maintained by thebreather systemFUEL (11)
1.What are float switches used for in the fuel system.
to controlrefuel/defuel valves
2.To what condition does the fuel flow respond during
aircraftacceleration.
mass airflow rate thru the engine
3 .An EEC is powered in f l igh t by.
N2 tachogenerator
oil
30.Type of oil system is usually found on turbine engines.
dry sump,pressure and spray
4.To stabilize cams, springs and linkages within the fuel
control,manufacturers generally recommend that all final turbine engine
trimadjustments be made in the.
increase direction
5.The maximum RPM of a turbine engine is limited by.
reduction of the fuel pump stroke by a spill valve sensitive to centrifugallygenerated fuelpressure
6.Kinetic valves are used because.
they are more sensitive
7.When a throttle is selected to increase power, the pressure drop acrossthe Fuel
Control Unit throttle orifice.
drops then increases due toincreasing pump output
8.During any stabilised running condition, the spill or half ball valveis.
lightly seated
9.With a decrease in fuel SG, what is the result when the engine isfittedwith an uncompensated fuel governor.
maximum RPM increases
10.An increase in fuel S.G. will cause.
a reduction in maximum RPM
11.What power supplies the EEC during normal operation.
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a dedicatedgenerator
12.A FADEC system takes measurements from enginespeed.
temperature and pressure
13.If the knife-edge blade in a kinetic valve is fully in.
servo pressure isbeing bled off14.A fuel heater prevents.
entrained water in fuel freezing
15.A fuel heater prevents.
LP filter icing
16.In a FADEC system, how are the power supply windings for channel Aand
channel B wound.
on one generator with 2 separatewindings
17.Out of the following thrust lever resolver angles, which one is theforward idle
setting.
40 degrees
18.When the EEC supervisory circuit senses a fault on the engine, thefault
annunciator light will be on and the EEC will.
remove fuel,down trimming signal immediately
19.BPC controls the FCU by.
pressure sensing
20.What is the primary purpose for trimming a turbine engine fuel controlunit
to obtain maximum thrust output when desired21.What would be the effect on the engine if the BPC half ball valve in theservo
line sticks open.
a reduction in fuel flow, therefore adecrease in RPM
22.A kinetic valve is a device used to control HP pump output. This isachieved by
movement of a..
knife blade
23.Which of the following inputs does the fuel control system combine tooperate a
gas turbine engine.
engine speed, altitude, exhausttemperature and throttle position24.In a FADEC system, the signal to the HMC is the differencebetween.
actual N1 and computed N1
25.Purpose of a fuel flow divider in a turbine engine duplex fuelnozzle.
creates the primary and secondary fuel supplies
26.Purpose of the LP fuel pump is to.
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ensure the HP fuel pump doesnot cavitate
27.Purpose of a silver strip on a fuel filter.
to detect sulphur in fuel
28.On approach.
RPM should be above the minimum idle formaximum acceleration29.Why is the high pressure fuel pump fitted in a gas turbine engine.
toprovide the majority of the fuel pressure to the engine
30.How is servo pressure, which is used to control fuel pump swash plateangle
obtained.
from pump delivery pressure through a fixedrestriction
31.During acceleration, the fuel flow is increased at a controlled rate inorder to.
prevent surge and the risk of flame-out
32.Where is the engine fuel shutoff valve usually located
downstreamof the engine driven fuel pump
33.Why is it necessary to control fuel supply to the engine during
rapidacceleration.
to prevent excessively high EGT and possiblecompressor surge
34.What moves the swash plate away from the minimum strokeposition.
a spring
35.During aerobatic manoeuvres, what prevents fuel form spilling out of fuel tank
vents.
float operated valves36.Which of the following influences the operation of an automatic fuelcontrol unit
on a turbojet engine.
burner pressure
37.The basic concept of an HP fuel control is.
constant adjustment of the swash plate angle of the HP fuel pump
38.A FADEC consists of.
electronic controls (EEC), sensors and anHMU
39.During acceleration, the fuel flow is increased at a controlled rate inorder to.
prevent surge and the risk of flame out40.A fuel trimmer unit is adjusted at altitude.
automatically via a fueltrim unit
41.The fuel trimmer on a turbo-prop engine is operated.
automaticallycontrolled in conjunction with FCU
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42.When considering a centrifugal type engine speed governor, n increasein fuel
S.G. will cause.
a reduction in maximum RPM
43.A barometric pressure controller controls.
fuel flow to suitatmospheric pressure changes44.The burner fuel flow is at a maximum at.
I.S.A. sea level
45.What must be done after the FCU has been replaced..
retrim theengine
46.On an engine powered by a FADEC, each engine has.
1 FADEC withone channel active and the other channel monitoring with itsoutput
drivers de-energised
47.The position of fuel heater in fuel system is.
before the LP fuelfilter
48.HMU receives signals form.
EEC
49.The EEC receives its primary power from.
separate permanentmagnet alternator
50.In a FADEC system, what is the result of channel A failing to reciveinformation
from a sensor.
channel A will take the info fromchannel B
51.Why is an ACU fitted to a gas turbine engine..it limits the rate of increase in fuel flow during sudden acceleration
52.The swash plate in a fuel pump when static is.
in the maximumposition
53.When trimming a turbine engine, the fuel control is adjusted to.
setidle RPM and maximum speed or EPR
54. In flight, the engine EEC controls.
fuel flow
55.To prevent compressor surge and overheating of the combustionchamber due to
over fuelling..an acceleration control unit (ACU)is fitted
56.In a FADEC system, what determines which channel is incontrol.
whichever is the best channel
57.What are the positions of the pressurization valve and the dump valvein a jet
engine fuel system when the engine is shutdown.
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pressurization valve closed, dump valve open
58.What would be the effect on the engine if the BPC half ball valve in theservo
line sticks open.
a reduction of fuel flow, therefore adecrease in RPM
59.Why is a hydro-mechanical governor fitted to a gas turbine engine fuelpump.to enable the engine to operate over a wide range of SGs
60.The density of air is very important when mixing fuel and air to obtaina correct
fuel to air ratio. Which of the following weighs themost.
100 parts of dry air
61.What causes the fuel divider valve to open in a turbine engine duplexfuel
nozzle.
fuel pressure
62.Baffles in a rigid fuel tank.
prevents surge
63.Why is the barometric pressure controller (BPC) fitted in a turbo-shaftengine fuel
system.
to vary pressure pump output in relation tothe pressure variation at the intake
64.Which valve ensures the adequate fuel flow.
the fuel meteringvalve
65.Specific fuel consumption at altitude will.
remain constant
6.If the swash plate of a positive displacement swash plate pump isperpendicular tothe axis of the pump, the flow will be.
zero
67.What are the principal advantages of the duplex fuel nozzle used inmany
turbine engines.
provides better atomization and uniformflow pattern
68.After a bag tank replacement, where would you disconnect the systemto carry
out the flow checks.
at the engine
69.What is the purpose of the attenuator fitted between the HP fuel pumpand theBPC in a fuel system.
it damps out pulsations in the fueldelivery to the BPC
70.Conditions when trimming of a turbine engine be most accurate.
nowind and low moisture
71.Opening of fuel valve after shut down will cause.
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risk of fire inturbine
72.When a re-light is required in flight on a FADEC engine.
igniter isselected automaticallyAIR SYSTEMS (12)
1.Bleed air pressure and shut-off cock pressure is...
200psi2.Turbine case cooling utilizes...
fan air
3.If air is taken from the compressor for air cond / anti-icing...
thrust willdecrease, EGT will increase
4.Engine anti-ice is taken from...
HP compressor
5.In an axial flow turbine engine, compressor bleed air is sometimesused to aid in
cooling the...
turbine, vanes, blades and bearings
6.Air bleed for an anti-ice system is...
sent through a pressureregulator
7.When electrical anti-icing is on...
power decreases
8.Anti-ice bleed is controlled by...
regulator valve
9.On a gas turbine engine, thermal wing de-icing system derivesair...
through a pressure regulating shut-off valve (PRSOV)10.Inlet for cooling air for the 1st stage turbine blades are fed viathe...
blade rootSTARTING AND IGNITION SYSTEMS (13)
1.In a gas turbine engine dc capacitor discharge ignition system, whereare the high
voltage pulses formed
at the triggering transformer
2 . I n t h e H E I U t h e c h o k e
.prolongs the discharge
3 .A hot s ta r t i s assoc ia ted wi th.
high EGT4.A safety feature usually employed in pneumatic starters that is used toprevent the
starter from reaching burst speed if inlet air does notterminate on schedule is
the..
stator nozzle design that chokesairflow and stabilizes turbine wheel speed
5.Advantage of pneumatic starter over electric starters is.
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high power-to-weight ratio
6.An igniter plug for a large gas turbine takes the form of a.
surfacedischarge plug
7.When removing turbine engine igniter plug, to eliminate possibility of receiving
a lethal shock, the ignition switch is turned off and..thetransformer exciter input lead is disconnected and the centreelectrode grounded to the
engine after disconnecting theigniter lead from the plug and waiting the prescribed time
8.Pneumatic s tar ters are usual ly designed with what types of
airflowimpingement systems.
redial inward flow turbine and axial-flowturbine
9.Voltage at the igniter plug depends on.
gap in the ignition systembox
10.A starter has 2 hole to check the.
level of oil
11.A glow plug may be used in place of a spark plug on.
small engines
12.An electrical starter-generator is.
series wound with high torque
13.On a gas turbine engine DC starting circuit, if there is an open circuiton the
contact of the over speed relay.
no supply is connected tothe starter motor
14.To avoid lethal electric shock from ignition system, ground.theignition lead
15.A hot start with excessive temperatures may be caused by.
throttlepartly open
16.High energy ignition is required because of the
.high flash point of the fuel
17.The resistor in a DC starter motor.
prevents current surge whenmotor is at low rpm
18.Purpose of the current limiting resistor in a starter circuit
.is toprevent an initial current surge19.On a low energy dual ignition system (
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21.A HEIU is rated in
joules
22.A DC starter motor disconnects due to.
current decreasingswitching off an overspeed relay
23.Why do turbine engine ignition systems require high energy.toignite the fuel under conditions of high altitude and low temp
24.A clicking sound heard at engine coast-down in a pneumatic starterincorporating
a sprag clutch ratchet assembly is a n indication of.
thepawls re-contacting and riding on the ratchet gear
25.Air turbine starters are generally designed so that reduction geardistress or
damage may be detected by
.inspection of a magneticchip detector
26.In the HEIU, the discharge resistors.
allows the capacitors todischarge when the unit is switched off
27.When is ignition used.
for relight and start up
28.Type used on turbine engine.
capacitor discharge
29.A safety feature usually employed in pneumatic starters that is used if the clutch
does not release from the engine drive at the proper timeduring start is the.
drive shaft shear point
30.A dry motoring cycle would be required to.clear engine after a wetstart
31.A glow plug.
operates electrically.used on small engines
32.Caution when handling damaged hermetically sealed turbine ignitertransformer
because.
some contain radioactive material
33.A HEIU works by.
a discharging capacitor
34.When an engine being started by an air starter reaches self sustainingspeed.the starter valve is disconnected by the fly weight cut-out switch in the starter
35.After an unsuccessful start of a n engine.
unburnt fuel can beevacuated by
motoring the engine with HP cock closed
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36.Voltage at the igniter plug is.
governed by the air gap in the HEIUbox
37.In a gas turbine engine DC capacitor discharge ignition system whereare the
high voltage pulses formed.
at the triggering transformer38.The field of the DC starter motor used on gas turbine engineis.
series or compound
39.The purpose of an under current relay in a starter-generator system isto.
disconnect power from the starter-generator and ignitionwhen sufficient engine speed
is reached
40.In an electrical starting system, the slow start resistor is short circuitedby the.
time switch
41.First instrument indication of a successful start of a turbine engine.
arise in the exhaust gas temp
42.Inspection of pneumatic starters by maintenance technicians usuallyincludes
checking the.
oil level and magnetic drain plugcondition
43.Turbine blade is most commonly used in air starter motors.
Impulse
44.If the engine fails to light-up, the starter cycle is cancelled by.
a timeswitchENGINE INDICATING SYSTEMS (14)
1.In what units are gas turbine engine tachometers calibrated.percentof engine RPM
2.Fuel f low is measured in.
lbs/hrs or kg/hrs
3.Instruments that measure relatively high fluid pressures, such as oilpressure
gauges are usually what type.
bourdon tube
4.A common type of electrically operated oil temp gaugeutilizes.
either a wheatstone bridge or ratiometer circuit
5.EGT indicator on a gas turbine engine provides a relative indication of the.turbine inlet temp
6.Engine pressure ration is the total pressure ratio between the
frontof the compressor and the rear of the turbine
7.What happens when bulb type thermometer resistive element goesopen
circuit.
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reads more than ambient
8.In a thermocouple temp sensing system, what is the purpose of
thecompensating resistor.
to correct for varying ambient temp atthe cold junction
9.What power supply is required for a thermocouple systemwork.neither of the above
10.Thermocouple metals most frequently used are.
constantan andcopper
11.Regarding an engine EGT detection system, which of the followingstatements
is true.
chromel is positive and alumel is negative
12.How are EGT thermocouples connected.
parallel
13.Motor driven impeller and turbine fuel flow transmitted are designed totransmit
data.
using aircraft electrical system power
14.Fuel flow indication is taken from.
after either HP pump or LPpump
15.In a tachometer generator.
frequency output is proportional toengine
speed16.A thermocouple indicator is basically a.
milivoltmeter17.Instruments that provide readings of low or negative pressure, such asmanifold
pressure gauges are usually.
diaphragm and bellowstype
18.The gauge on a bulb type temp indicator shows zero. This could becaused by.
two cables shorting together by the sensor
19.What unit in a tachometer system sends information to theindicator.
3 phase AC generator
20.In a multi-thermocouple loop, if one thermocouple goes open circuit,the
indication..will have no effect on temp indication
21.Vibration signals when picked up.
the frequencies are filtered toexclude unwanted frequencies
22.A tachogenerator to indicate revs/min requires.
no power
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23.N2 is taken from.
a tachometer on the accessory gearbox
24.A thermocouple indicator is connected to the.
cold junction
25.EGT gauge indication.needs NO POWER, it is self generating
26.When testing an EGT system.
the OAT is always taken intoconsideration
27.What instrument on a gas turbine engine should be monitored tominimize the
possibility of a Hot Start.
turbine inlet temp
28.The indication on a thermocouple-type EGT indicator is producedby.
a current generated by the temp difference betweendissimilar metal hot and cold
junctions
29.On an aircraft turbine engine operating at a constant power, theapplication of
engine anti-icing will result in.
noticeable shift in EPR
30.What will the EPR reading be if the P1 sensor probe becomes blockedon take-
off.
EPR reading higher than actual
31.Thrust in a high bypass fan engine is indicated by.
N1 RPM or EPR32.What indication is available to show that thrust reverser has beenselected.
an amber reverser unlocked light illuminates
33.Torsional deflection in a turboprop engine shaft is an indication of
whatvariable.
horsepower
34.Thrust in a high bypass engine.
is not indicated in flight
35.A ballast resistor is fitted
in series, to give identical resistancevalues to all airframe36.Torque pressure is usually read from a.
direct reading pressuregauge
37.Modern oil pressure servo transmitters sense.
differential pressure
38.Engine oil temp gauges indicate the temp of the oil.
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at the oil cooler
39.On an EGT thermocouple system, the hot junction.
placeddownstream of the combustion chamber
40.Motor driven impeller and turbine fuel flow transmitters are designedto transmit
data.using aircraft electrical system power
41.EGT is displayed in.
degrees celsius
42.Torque measurement in a gas turbine engine is.
required onlywhen the turbine drives a propeller
43.EGT thermocouples are usually made of.
chromel and alumel
44.Oil temp thermocouples are usually constructed of
iron constantan
45.A red triangle, dot or diamond mark on an engine instrument face orglass
indicates.
the maximum limit for high transients such asstarting
46.On an RPM system using a synchronous generator, the pointer isdeflected by.
an AC servometer
47.On an aircraft turbine engine operating at a constant power, theapplication of
engine anti-icing will result in.
noticeable shift in EPR48.A CIT sensor is made up of.
platinum-rhodium
49.Why do helicopters require a minimum of two synchronous
tachometersystems.
one indicates engine RPM and the other main rotorRPM
50.In addition to fuel quantity, a computerized fuel system (CFS) with atotalizer
indicator provides indication of how many of the
following.
fuel flow rate, fuel used since reset or initial startup, fuel time remaining at current powersetting
51.If the thermocouple leads were inadvertently crossed at installation,what would
the EGT gauge pointer indicate.
moves off scale on thezero side of the meter
52.Thermocouple leads.
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are designed for a specific installation andmay not be altered
53.The fuel flow indication data sent from motor driven impeller andturbine, and
motorless type fuel flow transmitters is a measureof.
fuel mass flow
54.Engine pressure ration is determined by.dividing turbine outlettotal pressure by engine inlet total pressure
55.In a capacitive type fuel quantity indicating system the tank units areconnected
.in parallel
56.The resistance of a temp bulb is.
increases with an increase intemp
57.The indicator of a tachometer system is responsive to changein.
frequency
58.The RPM indication of a synchronous AC motor tachometer is governedby the
generator.
frequency
59.How is the N! and N2 measured on a triple spool engine.
pulse typespeed probes
60.The compensation device on an EGT system..
does not needcalibration
61.Integrating fuel flow gives.
total fuel consumed
62.In a thermocouple system, the size of the EMF that is produced is aresult of.the difference between the hot and cold junction
63.What is the primary purpose of the tachometer on an axial compressorturbine
engine.
monitor engine RPM during starting and toindicate overspeed conditions
64.Engine vibration is monitored using.
piezoelectric accelerometer
65.The turbine discharge pressure indicator sensor islocated
.immediately aft of the last turbine stage
66.Where is Turbine Outlet Temperature (TOT) measured.downstreamof the turbine
67.If there is a restriction in the oil pressure line, the gauge will.
readlow
68.A bourdon tube instrument may be used to indicate.
pressure andtemperature
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69.Vibration pick-ups are located.
on both fan and turbine cases
70.On an EGT thermocouple system, the hot junction
.is placeddownstream of the combustion chamber
71.thrust in a bypass engine.is not indicated in flight
72.The fuel flow indicator rotor and needle for a motor impeller andturbine
indicating system is driven by.
an electrical signalPOWER AUGMENTATION SYSTEMS (15)
1.Water methanol injection is used
at a combination of higher thannormal air temp & high altitude take off conditions
2.During operation of the engine equipped with water injection system,the
metering of the coolant to the system is
due to atmosphericpressure
3.When reheat is selected and in operation, the mass gas flow
remainsthe same
4.The main reason for adding methanol to the water is to
preventmixture freezing
5.Methanol is added to water when augmenting thrust in order to
reclaim lost heat at the turbines
6.Water used in a thrust augmentation system should be demineralisedto prevent
fouling the blades and vanes7 .When reheat i s used , EPR
remains constant
8.On a turboprop engine, water methanol for cooling is injected intothe
compressor inlet or outlet
9 .Water /methanol i s in jec ted
at high temp or high altitudes
10.Afterburning is initiated in order to
increase the local speed of sound at the jet nozzle
11.When using water methanol in an axial flow compressor, it is injectedinto thecompressor inlet or burner section
12.How is the flame stabilised in the reheat system of a gas turbineengine
by ensuring that the gas velocity is grater than theflame velocity
13.Injection of water/methanol into compressor inlet causes
increase inpower without the need for burning extra fuel
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14.Water methanol injection will increase thrust by up to
30%
15.Screech liners in the afterburning jet pipe
prevents cyclicvibrations of large amplitude
16.The primary purpose of water injection is tocool the turbine
17.Water or water/methanol injected into the combustion chamber inletincreases
mass airflow through the turbine
18.Reheat is the term used to describeadding
fuel in the exhaustsection
19.The reheat ignition system which incorporates a platinum/rhodiumelement is
known as
catalytic ignition
TURBO-PROP ENGINES (16)
1 . I f an EPR gauge i s ins ta l led on turbofans as a measure of power
output,what is used on a turbo-prop
torque meter
2 .What type of reduction gear is used on most turboprop modern
engines
epicyclic reduction gear
3.In a turboprop the propellers produce75-85% of total thrust
4.Torque measurement is taken from the
reduction gearbox
5.A free turbine is usually found on a
turbo-prop
6 . A f r e e t u r b i n e i s
connected directly to the power output shaft
7 .A d i rec t d r ive tu rboprop engine
uses a reduction gearbox to reduceRPM of propeller8.A turboprop reduction gear is normally
10:1
9 .What cont ro ls the fue l t r immer on a tu rboprop engine
Engine SpeedGoverner
10.A propeller engine oil has
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higher viscosity than turbojets
11.The fuel flow in a turboprop engine within the constant speed range
iscontrolled
automatically
12.Fuel trimming on a turboprop engine isgoverner controlled
TURBO-SHAFT (17)
1.On a twin spool turbo-shaf t engine, the free turb ine is connected tothe...
output gearbox
2.A turbo-shaf t engine has . . .
a power shaft which is not connected tothe compressor
3.In the majority of helicopters, the thrust generated by the gasgenerator is
absorbed by the
...free power turbine
4.Which type of torquemeters are used on turbo-shaft engines...
electro-mechanical and oil
5 .A curv ic coupl ing . . .
accurately aligns the driving and driven shaftsAPU (18)
1.Usually most of the load placed on an APU occurs when
the bleedair valve is opened
2.The function of an APU air inlet plenum is tostabilize the pressureof the air before it enters the compressor
3.2 most important signals when monitoring APU
EGT and oilpressure
4 .An APU shut down i s in i t ia ted by
low oil pressure, fire warning,hot oil tem
p5.Electrical speed control switches on an APU are set at
35%, 95% and100%
6.An APU start cycle is completed at
95%7 . A n A P U c o n s i s t s o f
a power compressor and a load compressor
8.An APU is usually rotated during start by
an electric starter
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9.One of the accessories driven from the APU gearbox is a
centrifugalswitch, the purpose of which is to
cancel the ignition circuits andarm the overspeed protection circuits
10.APU cooling before shutdown may be accomplished by
closing thebleed air valve11.Generally, when maximum APU shaft output power is being used inconjunction
with pneumatic power
pneumatic loading will beautomatically modulated to maintain safe EGT
12.What initiates APU shutdown
fire detection, low oil pressure,high oil temperaturePOWERPLANT INSTALLATION
(19)
1 . F e e d e r s a r e
heavy duty electrical generator cables
2.The spring back and cushion on an engine power lever is
used toprevent the controls hitting the fuel control stops
3.Fibrous metallic lining for noise suppression is used
in hot area
4.Rubber anti-vibration pads are fitted to engine
pylons to preventvibration thru the airframe
5.The minimum bend radius for a continuous loop type fire wire
1 inch
6.Forward engine mounts take which loadsthrust, vertical and shearloads
7.What are installed in an engine mounting to tune out the worst
enginevibrations
rubber encased wire-mesh vibration isolators
8.Engine thrust is transmitted thru mountings that
allows for radialand axial expansion
9.Acoustic linings made from composite materials used on engine
coldsection only
10.Rubber clips which hold the electrical wires are used forheatabsorption
11.When checking the effect of inertia on the engine after heavy landing,check
the
module alignment firstFIRE PROTECTION SYSTEMS (20)
1.What are the types of continuous f ire detect ionsystem.
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capacitance and resistance
2.What is used as an extinguishant in fire bottles.
halogenatedhydrocarbons
3 . E l e c t r i c a l f i r e .
use carbon dioxide4.A fire detection system that operates on the rate of temp rise isa.
theromocouple system
5.Co2 ex t inguish f i re by.
contact with the air converts theliquid into snow and gas which smothers the flame
6.Rubber clips supporting a firewire is to
.insulate from enginevibration
7.In a resistance type firewire, when hot.
resistance decreases
8.A fire detection system operates on the principle of a buildup of gaspressure
within a tube proportional to temperature. Which of thefollowing systems does this
statement define.
Lindbergcontinuous element system
9.The following fire detection systems uses heat in the normal testingof the
system.
the thermocouple system and the Lindbergsystem
10.The safest fire extinguishing agent to use from a standpoint of toxicity and
corrosion hazards.bromotriflouromethane (Halon1301)
11.Fenwall fire detection system use spot detectors wired in parallelbetween two
separate circuits
.so that a single fault may existin the system without sounding a false alarm
12.When pulling fire handle.
closes fuel shut-off valve, hydraulicshut-off valve, disconnects the generator field and
arms thefire extinguishing system
13.The following fire detection systems will detect a fire when an element is
inoperative but will not test when the test circuit is energized.the Kidde system and the Fen wall system
14.A continuous loop fire detector is what type of detector.
overheat detector
15.Fire extinguishing agent distributed in the engine section.
spraynozzles and perforated tubing
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16.The most satisfactory extinguishing agent for an intake fire is.
drychemical
17.When testing a two pin fire bottle connector.
short two pinstogether
18.Fire extinguishing systems activated by.electrically dischargedcartridges
19.After a fire is extinguished or overheat condition removed in aircraftequipped
with a Systron-Donner fire detector, the detectionsystem.
automatically resets
20.The fire detection system that uses two wires imbedded in aceramic core within
a tube is the.
Kidde system
21.The test switch of a continuous loop detector gives a..
continuitycheckit is a overheat detector
22.A fuel or oil fire is defined as a.
Class B fire
23.A fire involving energized electrical equipment is defined asa.
Class E fire
24.Gas type fire wires operate by utilizing.
the change in the gas pressure
25.Methyl bromide fire extinguisher are installed with neck.
at the bottom26.Principle of operation of the continuous loop fire detector system sensor.
core resistance material which prevents currentflow at normal temp
27.Kidde fault free fire detection system has.
2 internal wires inthe sensing element
28.The fire detection system that uses a single wire surrounded by acontinuous
string of ceramic beads in a tube is the.
Fenwallsystem
29.The explosive cartridge in the discharge valve of a fire extinguishercontainer
is.a life dated unit
30.The operating principle of the spot detector sensor in a firedetection system
.a bimetallic theromoswitch that closeswhen heated to a high temp
31.When testing a squib on a fire bottle, you use a..
low currentohmmeter
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32.Which of the following fire detectors are commonly used in thepower section of
an engine nacelle.
rate of temp rise detectors
33.Fire wire clips have rubber in them to
.support the wireinsulate from engine vibration34.For fire detection and extinguishing purposes, aircraft powerplantareas are
divided into fire zones based on
the volume andsmoothness of the airflow thru engine compartments
35.Two continuous-loop fire detection systems that will not test due toa broken
detector element are the
Kidde and Fenwall System
36.The use of water on Class D fires.
will cause the fire to burnmore violently and can cause explosions
37.When testing an installed fire bottle
.a safety ohmmeter isused
38.On a fire bottle, if the indicator pin was protruding, this wouldindicate.
extinguisher had been fired
39.Omission of crushable washer on engine fire-wire connectorwill.
allow moisture ingress
40.Extinguisher spray rings checked for freedom from obstruction.
byblowing thru with compressed air41.When testing a squib on a fire bottle, use a.
low currentohmmeter
42.In a Fenwall fire detection system.
the tube is inconel and wireis nickel
43.What retains the nitrogen charge and fire extinguishing agent in ahigh rate of
discharge (HRD) container.
breakable disk orfusible disk ENGINE MONITORING AND GROUND OPERATIONS
(21)
1.Which of the following is the least likely indication of a mainbearingfailure
high oil pressure
2.First engine instrument indication of a successful start of aturbine
engine.
a rise in the exhaust gas temp
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3.Galling is a condition caused by excessive.
chafing
4.If a burner was down, in a multi-can system, the engine wouldtend to.
surge
5 .A Hot Star t re fers to.high EGT before idle RPM isachieved
6.Which engine variables is the most critical during turbine
engineoperation.
turbine inlet temp
7.Possible cause if a gas turbine engine has high exhaust gastemp, high
fuel flow and low RPM at all engine powersettings
.turbine damage or loss of turbine efficiency
8.After shutdown, flames are present in the exhaust pipe. Theprobable
cause is.
a defective pressurizing and dumpvalve
9.A cool-off period prior to shutdown of a turbine engine is doneto.
allow the turbine wheel to cool before the casecontracts around it
10.The recurrent ingestion of dust or other fine airborneparticulates into an engine
can result in.
erosion damage tothe compressor and turbine sections
11.If the run down time is less than the minimum stated for a givenengine.
the rotating assembly is being restricted12.In the event of stall occurring.
close throttle
13.Run down time is indicative of.
the freedom of rotation of the compressor
14.In regard to using a turbine engine oil analysis program, which isnot true.
generally, an accurate trend forecast may bemade after an engines first oil sample analysis
15.A rotation pad on an accessory drive gearbox is providedfor.
N2 rotation
16.A Hung Start is indicated by.failure to reach idle RPM
17.When the engine will not run up to idle after reaching startingspeed, the likely
fault is.
FCU
18.The blending of blades and vanes in a turbine engine.
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shouldbe performed parallel to the length of the blade usingsmooth contours to minimize
stress points
19.During start, if a bleed valve is stuck closed.
EGT will belower than normal
20.Starting an engine with a bleed valve stuck closed wouldcause.possible stalling of the engine
21.If a turbine engine is unable to reach take off EPR before its EGTlimit is
reached, this is an indication that the.
compressormay be contaminated or damaged
22.If a compressor surge occurs
coughing in the compressorand vibration occurs
23.Flame-out (lean) occurs due to
.low pressure at low enginespeeds
24.After an engine fails to light on start, u
may carry out a drymotor after a period of time prior to another startattempt
25.What should be done initially if a turbine engine catches firewhen starting.
turn off the fuel and continue enginerotation with the starter
26.A Wet Start is indicated by
.no temperature indication(due to lack of ignition)
27.What must not be used during an engine compressorwash.
chlorine28.Mark turbine components only with.
layout dye, commercialfelt tip marker or chalk
NGINE STORAGE & PRESERVATION (22)
1.Fuel system inhibiting oil is...
mineral oil
2.Which part of the engine is most likely fatal if hydraulic fluid was
toleak on it...
CPU
3.Installed engine must be re-preserved af ter preservation at leastevery...6 months
4.To inhibit the fuel system of an installed engine...
pump oil into theengine when stationary
5.When removing engine for long-term s torage, bleed valves shouldbe...
open but blanked
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6.Small cuts in a MVP engine storage bag can be repaired...
withadhesive PVC tapeUNVERIFIED (23)
1.Normal gas turbine engine stating sequence...
starter, ignition, fuel
2.Which material is used for gas turbine engine fuel lines...stainlesssteel