powerplant

Question 1

what are two types of turbine compressors?

Answer 1

centrifugal flow
&
axial flow

Question 2

what are three types of flow indicating systems used for turbine engines?

Answer 2

vane type

synchronous mass type

electronic motorless mass

Question 3

what do mass flow systems measure?

Answer 3

the mass of the flow
effected by density and temp

Question 4

in what units is an electronic motor less mass flow meter system calibrated?

Answer 4

pounds per hour

Question 5

what is indicated in a turbine engine if the fuel flow for all conditions is high?

Answer 5

if there are other instrument abnormalities , possible damaged turbine components

Question 6

who is authorized to repair a fuel flow indicating system?

Answer 6

FAA approved repair station certified for that particular instrument

Question 7

where can you find the electrical power requirements for a fuel flow indicating system?

Answer 7

aircraft maintenance manual

Question 8

where in the fuel system is the fuel flow transmitter located?

Answer 8

between the fuel control and fuel nozzles

Question 9

what kind of tachometer is used on most small single engine airplanes?

Answer 9

magnetic drag tachometer

Question 10

what would likely cause the pointer of a magnetic drag tachometer to oscillate?

Answer 10

Dry cable connecting the indicator to the engine

kink in the cable housinig

Question 11

what kind of tachometer is used on most large multi-engine airplanes?

Answer 11

Three phase AC electric tachometer

Question 12

what is measured to indicate the engine RPM with a three phase AC electric tachometer?

Answer 12

Frequency of the AC the tachometer generator produces

Question 13

what are two ways wires can be attached to the pins in a cannon plug?

Answer 13

soldering

crimping

Question 14

why is stranded wire rather solid wire used in most powerplant electrical systems?

Answer 14

solid wire is likely to break when subject to vibration

Question 15

what two things must be considered in selection of wire size when making electrical installation in an aircraft?

Answer 15

current carrying capacity

voltage drop

Question 16

what is used to protect a wire bundle from chafing where it passes through a hole in a bulkhead or frame?

Answer 16

Grommet

Question 17

how are electrical wires protected where they pass through an area of high temperature?

Answer 17

High temperature insulation
&
protective conduit

Question 18

what is the minimum separation allowed between a wire bundle and a fluid line that carries combustible fluid or oxygen?

Answer 18

6 inches

or non parallel to lines with a minimum of 2 inches

Question 19

which aircraft electrical circuit does not normally contain a fuse or circuit breaker?

Answer 19

starter motor circuit

Question 20

when should aircraft wiring be installed in a conduit?

Answer 20

when passing through an area to likely damage wiring

Question 21

what is meant by a trip free circuit breaker?

Answer 21

a circuit breaker that opens when excess current flows, regardless of the circuit breaker handle position

Question 22

which way should the toggle of a switch that controls the propeller pitch move to place the propeller in low pitch(high RPM)?

Answer 22

Forward

Question 23

why are protective covers placed over some switches in an aircraft electrical circuit?

Answer 23

prevents switch from accidentally being flipped

Question 24

what is straight mineral oil?

Answer 24

fractional distillation of crude oil
&
no additives

Question 25

what is ashless dispersant (AD) oil?

Answer 25

mineral oil with additives that prevents contaminants from clumping. & no ash forming additives

Question 26

what is synthetic oil?

Answer 26

oil made by chemically changing the nature of an oil base used in turbine engines

Question 27

is automotive oil suitable for use in aircraft engines?

Answer 27

NO

Question 28

what is meant by a multi-viscosity oil?

Answer 28

additive that increases viscosity when hot and lower viscosity when cold

Question 29

where can you find the grade of engine oil specified for particular aircraft?

Answer 29

airplane flight manual pilots operating handbook

Question 30

what are six functions of an oil?

Answer 30

1 friction 2 Heat 3 Hydraulic 4 seals and cushions 5 cleans engine 6 Corrosion

Question 31

what is the purpose of an air oil separator, or deaerator, in a turbine engine oil tank?

Answer 31

swirling action releases air from oil which is used to pressurize the oil tank

Question 32

how is oil pressure regulated in an aircraft engine?

Answer 32

pressure relief valve sends excess oil back into engine sump

Question 33

what is the purpose of the restricted orifice in the line between the oil pressure gauge and the engine?

Answer 33

dampens pulsations caused by the pump

Question 34

what is a hot tank lubrication system for a turbojet engine?

Answer 34

oil cooler is in the pressure subsystem scavenged oil is not cooled before returning to the tank

Question 35

what is a cold tank lubrication system for turbojet engine?

Answer 35

oil cooler is in the scavenge subsystem oil is cooled before returned to the tank

Question 36

where does a dry sump oil system store oil?

Answer 36

reservoir outside the engine

Question 37

what is the main advantage of a magneto ignition system over a battery ignition system for an aircraft reciprocating engine?

Answer 37

magneto has its own source for electrical energy, not dependent on battery

Question 38

what is an all weather spark plug?

Answer 38

shielded spark plug with recess for grommet forming water tight seal

Question 39

what is meant by the reach of a spark plug?

Answer 39

length of the threads that screw into cylinder head

Question 40

what is the difference between a hot and cold spark plug?

Answer 40

Hot spark plug- heat has a longer path from nose core insulator to shell. Cold spark plug- shorter distance equals cooler operation

Question 41

what is the advantage of the fine wire spark plugs over massive electrode spark plugs?

Answer 41

fine wire plugs have more open end allowing gases to be purged preventing solid lead contaminants from forming

Question 42

why is it important that the spark plugs be kept in numbered holes in a tray when they are removed from an engine?

Answer 42

knowing which cylinder the spark plug came from can help determine conditions such as detonation or overheating in each cylinder

Question 43

why is it important that torque wrench always be used when installing spark plugs in an aircraft engine?

Answer 43

prevents... poor seal & cracking insulation or threads

Question 44

what kind of gauge should be used to measure the electrode gap in an aircraft spark plugs?

Answer 44

round wire gauge

Question 45

what kind of electric starting system is used on many of the smaller turbine engines?

Answer 45

starter generator

Question 46

why are air turbine starters superior to electric starters for large turbine engines?

Answer 46

light weight for the torque they produce

Question 47

where does an air turbine starters get its air for starting the engines on a jet transport airplane?

Answer 47

APU GPU Running engine

Question 48

what prevents too high an air pressure from overspeeding an air turbine starter?

Answer 48

air shutoff and regulating valve

Question 49

where does an air turbine starters get its lubricating oil?

Answer 49

self contained lubrication system in the starter housing

Question 50

what device in an air turbine starters warns an aviation mechanic if there are any metal chips or particles in the oil?

Answer 50

magnetic chip detector

Question 51

what is the function of the capacitor in a magneto?

Answer 51

minimizes arcing at the breaker points speeds up collapse of primary current as breaker points open

Question 52

what happens in a magneto ignition system when the ignition switch is places in the off position?

Answer 52

primary circuit is connected to ground

Question 53

what is checked when a magneto is internally timed?

Answer 53

breaker points open at E gap position distributor positioned to cylinder 1

Question 54

in what position should the ignition switch be placed when using a timing light on the magnetos?

Answer 54

in the both position

Question 55

what is the E gap in magneto timing?

Answer 55

the position of the rotating magnet where current in magneto coil is greatest. (when breaker points open)

Question 56

what malfunction in the ignition system would cause an aircraft reciprocating engine to continue to run after the ignition switch is placed in the off position?

Answer 56

ignition switch is not grounding the magneto primary circuit

Question 57

are the instruments installed in an aircraft suitable for use when trimming an turbine engine?

Answer 57

NO

Question 58

where are the fuel strainers normally located in an aircraft fuel system?

Answer 58

Tank outlet lowest point in the fuel system carb or fuel injection system

Question 59

how can you tell when a fuel strainer for a turbine engine has been bypassed?

Answer 59

red indicator button will pop out

Question 60

what are the two types of fuel injection systems used on modern reciprocating aircraft engines?

Answer 60

Bendix & TCM

Question 61

what is used in the TCM fuel injection system to control the amount of fuel sent to the nozzles?

Answer 61

Engine speed for injector pump output Orifice for high speed relief valve for low speed

Question 62

what is used in the precision airmotive system to control the amount of fuel sent to the nozzles?

Answer 62

air mass entering the engine acts on a diaphragm that controls a servo ball valve in the line between regulator and flow divider.

Question 63

what does a fuel injected engine have that prevents the loss of the induction air if the air inlet filter should become covered with ice?

Answer 63

alternate air valve allows warm air from engine cowling into the fuel metering system

Question 64

what would be the effect on engine operation of an air leak in the intake pipe for one cylinder?

Answer 64

cylinder runs lean causes detonation

Question 65

what must be inspected on the cooling system of an air cooled engine?

Answer 65

baffles & air seals must be in place and in good condition

Question 66

why should an air cooled engine not be run up to high power without the cowling installed?

Answer 66

cowling forces air through cylinder fins for cooling

Question 67

why do some air cooled engine installations have cowl flaps?

Answer 67

cowl flaps create low pressure on one side of engine pulling air through cooling fins

Question 68

what document describes the proper use of cowl flaps on an air cooled engine?

Answer 68

pilots operating handbook

Question 69

what are three main parts of a typical turbo supercharger?

Answer 69

compressor assembly turbine wheel assembly full floating shaft assembly

Question 70

how is a turbosupercharger (turbocharger) driven?

Answer 70

engine exhaust gases directed against the turbine, which drives and impeller that compresses the incoming air

Question 71

how is a supercharger driven?

Answer 71

directly from the engine and is internal to the engine

Question 72

what is the primary design concern of a turbine engine inlet?

Answer 72

flow of air into the compressor should be free of turbulence to achieve maximum operating efficiency

Question 73

what is the compressor pressure ratio?

Answer 73

outlet pressure divided by inlet pressure

Question 74

what does the pilot do to change the RPM of an engine quipped with a constant speed propeller when it is operating within the constant speed range?

Answer 74

Pilot moves the propeller pitch control... this changes compression on the speeder spring... this moves the pilot valve, which directs oil into or out of the propeller

Question 75

what is the difference between a controllable propeller and a constant speed propeller?

Answer 75

controllable pitch propeller uses a manually operated oil valve constant speed propeller uses a governor to control the valve

Question 76

when making a magneto check on an engine equipped with a constant speed propeller, should the propeller control be in the low pitch or the high pitch position?

Answer 76

low pitch, high RPM