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ATPL Theory > AGK Engines > Flashcards

AGK Engines Flashcards

1
Q

Ignition Timing…

A

Is performed by the magnetos .

Is necessary as it takes a finite time for the mixture to burn.

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2
Q

Which engine initiates combustion by the heat of compression

A

Deisel engine

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3
Q

Which engine uses a spark to initiate ignition

A

Petrol engine

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4
Q

Name the strokes in a 4 stroke engine

A

Induction, Compression, Power, Exhaust

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5
Q

Flame rate of aviation fuel mixed with air

A

60/80 ft per second
(18-24m)

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6
Q

The crank assembly is comprised of…

A

Crankshaft
Connecting rods
Pistons

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7
Q

Hydraulic tappets are used to…

A

automatically adjust the tappet clearance

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8
Q

Why are valves often filled with sodium ?

A

To take heat away

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9
Q

Name 4 EMF variables

A

Magnet size
Conductor length
Perpendicular angle
Rate of charge

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10
Q

How long should the starter operating light take to switch off ?

A

30 Seconds

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11
Q

An impulse coupling..

A

Gives you a higher energy retarded spark.

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12
Q

A high tension booster is…

A

A vibrator directly connected to the high tension side. (shower of sparks)

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13
Q

A low tension booster is…

A

A set of pulses to the primary circuit (low tension side)

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14
Q

Pre flight magneto checks are…

A

Drop check
Dead cut check

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15
Q

RPM drop range on a drop magneto check

A

Drop of 100-175 indicates normal magneto operation.
Drop greater than 400 means there may be a faulty spark plug and should be reported immediately.

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16
Q

A blocked spark plug gap is said to be …

A

Fouled

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17
Q

A spark plugs body forms an…

A

Electrode

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18
Q

AVGAS is made up of ?

A

15% carbon 85% hydrogen

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19
Q

Octane rating is…

A

A measure of resistance to detonation

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20
Q

Detonation flame rate ?

A

1000 ft/s

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21
Q

what colour is AVGAS 100LL

A

Blue
and environmentally better

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22
Q

What colour is AVGAS 100

A

Green
and environmentally worse

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23
Q

A fuel sample must be…

A

Clear and bright
Free of sediment
No entrained water
have a max water content of 30ppm

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24
Q

Detonation causes

A

Fuel with too low octane (poor anti knock)

Incorrect (weak) mixture

Anything that could unduly raise temperature or pressure.

High engine temperature

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25
Q

Pre ignition causes

A

Hot debris within the cylinder
(typically carbon deposits)

Ignition malfunction (damaged spark plug)

High cylinder temperatures

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26
Q

Mixture ratios

A

20:1 Lean (increased detonation risk)
15:1 Chemically correct (ideal ratio)(EGT Peak)
8:1 Rich (increased detonation risk)

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27
Q

Takeoff and cruise mixes should be..

A

Takeoff 11:1
Cruise 17:1

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28
Q

Ineffective crank angle is ?

A

The period of relatively little movement of the piston around the TDC and BDC

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29
Q

Inlet valve lag is when…

A

The inlet valve remains open just after BDC as the compression stroke begins to help fill the chamber. The valve closes just after the piton leaves the ineffective crank angle.

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30
Q

Inlet valve lead is when…

A

Inlet valve opened early, just before TDC, exhaust valve is still open at the end of the exhaust stroke

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31
Q

Exhaust valve lead is when…

A

Both valves are closed at the start of the power stroke, most of the work is done before the piston reaches BDC, so the exhaust valve opens before the end of the power stroke. Provides a longer period to clear the cylinder of waste gasses.

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32
Q

Exhaust valve lag is when…

A

The exhaust valve remains open until slightly after the TDC, remaining gas exits under its own momentum.

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33
Q

TDC

A

Top Dead Center

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34
Q

BDC

A

Bottom Dead Center

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35
Q

Where does valve overlap occur ?

A

Around TDC between the exhaust and induction strokes.

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36
Q

Prime carburettor icing temperature and key condition ?

A

+18 to +25 C
and high humidity levels
Low power levels

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37
Q

Carb icing prevention ?

A

Carburettor heating

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38
Q

Carb icing symptoms ?

A

Loss of rpm
Reduced inlet MAP
Decreased EGT
Rough running
Jammed throttle
Engine stops

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39
Q

Carburettor alternative ?

A

Fuel injection, fuel is injected to the cylinders directly so no need for a carburettor.

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40
Q

Diesel engine is primed how ?

A

By using the accelerator pump

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41
Q

Fuel must …

A

Have a lot of energy
Be able to form a vapour
Be able to burn quickly

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42
Q

AVGAS has a SG of …

A

0.72 at 15 C

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43
Q

what can occur if fuel vaporises in the fuel lines or pumps. This causes partial or complete loss of engine power.

A

Vapour lock

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44
Q

What is the extremely rapid chemical decomposition of the mixture after burning has begun. May be heard as knocking sound.

A

Detonation

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45
Q

What is the ignition of the mixture before the spark plug has sparked. Caused by hot spots in the cylinder.

A

Pre-ignition

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46
Q

Symptoms for pre-ignition and detonation ?

A

Rough running
Power loss
Overheating

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47
Q

What is added to fuel to reduce detonation ?

A

Lead
AVGAS 100LL (Low lead)

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48
Q

What is the stoichiometric fuel mix ?

A

15:1, but cannot be used as engine would overheat

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49
Q

Which engine has a lower power to weight ratio, Why ?

A

Diesel
They are heavier but have the same output as a lighter petrol engine and lower max RPM. But it has a greater compression ratio

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50
Q

What is a carburettors purpose ?

A

To mix fuel and air to the correct ratio. Fuel is supplied by an engine driven pump. Air is supplied via the air intake.

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51
Q

How is mixture manually controlled ?

A

A mixture control lever in the cockpit

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52
Q

At low power setting the butterfly valve is… ?

A

Almost closed

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53
Q

Pre-ignition is ?

A

The ignition of mixture before the spark plug has fired

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54
Q

RPM gauge measures ?

A

Crankshaft RPM

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55
Q

Manifold pressure gauge ?

A

Measures manifold pressures in InHg

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56
Q

Boost pressure gauge ?

A

Measures manifold pressure in PSI relative to sea level pressure

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57
Q

Oil pressure gauge ?

A

Measures oil pressure just after the oil filter

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58
Q

Oil temperature gauge ?

A

Measures oil temperature in oil return line

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59
Q

CHT gauge ?

A

Measures the temperature of the hottest cylinder

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60
Q

EGT gauge ?

A

Measures the temperature of the exhaust gas stream

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61
Q

Fuel pressure gauge ?

A

Measures the fuel pump output pressure

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62
Q

Induction temperature gauge ?

A

Measures the carburettor inlet temperature

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63
Q

Camber line and chord line are between ?

A

Leading and trailing edge
Chord is the length of the chord line

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64
Q

Does a petrol or diesel engine have greater thermal efficiency ?

A

Diesel.
It has a higher compression ratio; 20:1 whereas petrol engines only have a 10:1 ratio.

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65
Q

What device is fitted to measure cylinder head temperature effectively ?

A

A Thermocouple

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66
Q

Engine PWR output ?

A

Torque x RPM

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67
Q

how is magneto switched off ?

A

Grounding the magneto

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68
Q

What happens to AoA of a fixed pitch prop as A/C accelerates along a runway ?

A

Decreases

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69
Q

Rich mixture in climbing segments results in ?

A

A gradually rich mixture as you climb (less dense air)

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70
Q

Why does a cylinder have 2 spark plugs ?

A

It reduces time for complete combustion

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71
Q

How is impeller driven ?

A

Diversion of exhaust gasses by waste gate, using energy that would otherwise be wasted

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72
Q

What is the angle between the blade chord and the plane of rotation ?

A

Blade pitch

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73
Q

Flat rating is used in what ambient conditions ?

A

Cold

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74
Q

What does jet thrust vary with

A

Altitude
Air density
Air speed
Engine RPM

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75
Q

Hot and high conditions are associated with… ?

A

The least thrust available from the engine

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76
Q

Propulsive power is … ?

A

Thrust x Aircraft velocity

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77
Q

RAM effect is associated with ?

A

High airspeed

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78
Q

Combustion occurs at a constant … ?

A

Pressure

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79
Q

What does a compressor do to gas flow ?

A

Gives it energy

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80
Q

Flat rating is used in what conditions ?

A

Cold

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81
Q

Constant speed propeller… ?

A

Adjusts pitch to ensure propeller runs at optimum RPM for airspeed

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82
Q

How is blade pitch altered ?

A

PCU in the propeller hub

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83
Q

Coarse pitch …?

A

Absorbs most power, creates most rotational drag

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84
Q

Fine pitch… ?

A

Absorbs the least power

Creates a lot of rotational drag if not running (Engine failure)

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85
Q

What prevents blades from going fully coarse on engine shut down ?

A

Centrifugal latch

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86
Q

Feathered blades are ?

A

Fully coarse to provide the minimum drag

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87
Q

Un-feathering is ?

A

Putting the blades to a finer pitch to allow engine restart in flight

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88
Q

What is fitted to multi engine aircraft to prevent problems caused by asymmetric drag ?

A

Auto-feather system

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89
Q

How is reverse thrust achieved ?

A

By setting the pitch to behind fully fine
(Beta range)

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90
Q

How is reverse thrust prevented ?

A

Weight on wheels operated fine pitch stop

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91
Q

How is cabin noise reduced ?

A

Synchronising or synchrophasing to avoid build up of pressure waves

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92
Q

How to avoid over boosting ?

A

Rev up: Power back

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93
Q

When must CSU operation be checked ?

A

Before flight, done by operating RPM lever

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94
Q

Which system always has a governor fitted ?

A

Constant speed, variable pitch

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95
Q

What sound frequency is produced from a propeller engine commonly

A

90 Db

96
Q

Fining blade pitch … ?

A

Increases RPM

97
Q

What pitch is wanted for landing and takeoff ?

A

Fine pitch

98
Q

Ideal cruise pitch ?

A

Coarse

99
Q

How is the propeller driven ?

A

Engine torque (RPM)

100
Q

Impact on AoA on a variable pitch prop with increase or decrease of TAS and RPM ?

A

It remains the same

101
Q

Effect of TAS on AoA on a fixed pitch prop ?

A

AoA is inversely proportional to TAS
(TAS increases AoA decreases)

102
Q

What does LP spool comprise

A

LP compressor or fan
LP turbine
Shaft

103
Q

What does HP spoil comprise

A

HP compressor
HP turbine

104
Q

For optimal efficiency… ?

A

Fan must run at relatively low RPM
Core must run at a very high rpm
Multiple spools allow this to happen

105
Q

Bypass ratio is ?

A

The ratio of bypass air mass flow to core mass flow.
( air entering the core Vs air going in bypass duct.
If 10 tonnes of air enter inlet, and 1 comes out the exhaust, bypass ratio is 9:1)

106
Q

What do some turbine engines have to drive the propeller ?

A

Free turbine

107
Q

Pure turbojet has no ?

A

Bypass duct
Exhaust jet velocity is very high instead

108
Q

An engine which uses a gas turbine to drive a helicopter rotor is a ?

A

Turbo shaft

109
Q

Advantage of multi spool designs is ?

A

Each spool runs at its optimum speed

110
Q

Most moderns commercial jet aircraft use ?

A

Turbofan engines

111
Q

Read part of pitot-style inlet forms a …?

A

Divergent duct

112
Q

Pitot style inlet cannot guarantee stable inlet conditions:

A

When contaminated with ice
At very high angle of attack
In severe turbulence
I’m very high crosswinds

113
Q

Air inlet fan has sensors to detect

A

Inlet temperature
Inept pressure
(Amongst other things)

114
Q

Nacelle functions ?

A

Reduce compressor noise
Provide structure for bypass duct
Streamline engine installation
Protect external engine components

115
Q

Two types of compressor ?

A

Centrifugal
Axial flow

116
Q

Compression ratio on a centrifugal compressor ?

A

4.5:1 per stage
A maximum of 2 stages in series can be employed

117
Q

What is a “stage” in an axial flow compressor ?

A

A set of rotating rotors and stationary stators, axial flow compressor comprises many stages

118
Q

Axial flow compression ratio ?

A

1.1-1.2:1 (10-20%) per stage

119
Q

What happens to Velocity pressure and temperature going through a rotor ?

A

Velocity - Increases
Pressure (static) - decreases
Temperature - Increases

120
Q

What happens to velocity, pressure and temperature in a stator ?

A

Velocity - decreases
Pressure (static) - increases
Temperature - increases

121
Q

Variable Inlet guide veins … ?

A

Swivel to deliver air at correct AoA to first stage of compressor

122
Q

Why is clearance between rotor sections and compressor case very small ?

A

To prevent tip losses

123
Q

Diffuser role ?

A

Converts kinetic energy into static pressure

124
Q

Stall or surge indicators

A

Low RPM
Banging noises
High temp

125
Q

Axial compressors are vulnerable to … ?

A

Foreign object damage

126
Q

Positives of centrifugal compressor

A

Less prone to surges
Less susceptible to FOD
Shorter, so more compact engines
Reasonably Efficient

127
Q

Negatives of a Centrifugal compressor

A

Low compression ratio
Less efficient than an axial flow compressor
Requires larger frontal area

128
Q

Axial Flow compressor P+N

A

Very efficient
High compression ratio

Vulnerable to FOD
Can suffer aerodynamic instability

129
Q

Stall and surge cheats

A

Multiple stools
Bleed valves
Variable inlet guide veins (VIGV) or variable station valves (VSVs)

130
Q

Stall and surge avoidance

A

Before flight check for ice and damage
Avoid starting in cross or tailwind
Avoid extreme angles of attack

131
Q

The entire axial flow compressor is located in … ?

A

A convergent duct to help sustain airflow against rising static pressure

132
Q

Flow reversal through an axial flow compressor is called ?

A

Compressor surge

133
Q

Diffuser at the back of an axial flow compressor uses a …. Duct ?

A

Divergent

134
Q

External air bleed- alternate name + uses

A

Customer bleed
To supply hot air or high pressure to aircraft systems, such as air con or anti icing
Can be switched off manually.

135
Q

Internal Air bleed functions

A

Spinner anti icing
Pressurised internal cavities
Pressurised bearing housings

136
Q

How to stop an internal engine over heat ?

A

Turn off engines

137
Q

Role of combustion chamber ?

A

To mid air and fuel to allow efficient burning

138
Q

Pressure across Gas turbine engine ?

A

GTE is a constant pressure engine, combustion does not create an increase

139
Q

How does the distribution of air go into the combustion chamber ?

A

20% goes through a ‘snout’ in ceramic lining, 80% goes around

140
Q

Air fuel ratio in GTE

A

45-130:1
In the flame is 15:1

141
Q

What does a primary airflow feed ?

A

Combustion flame, via a swirled valve and recirculating vortex.
Reducing airflow speed to 3 m/s

142
Q

Where is gas ignited ?

A

Primary zone

143
Q

What does a combustor drain do ?

A

Allows pooled fuel to drain away preventing a hot start or torching

144
Q

Cannular combustion chambers

A

Multiple chambers, Lots of little flames, lots of cooling tubes.

145
Q

Turbo annular combustion chamber

A

Radially placed, multiple flame tubes with different nozzles.

146
Q

Annular combustor (modern)

A

Fuel nozzles arranged radially injecting into one large flame tube

147
Q

Air spray injectors

A

Takes in air to creates a swirl and mixes it with fuel to make a toroidal flame in the primary zone, controlled by FADEC

148
Q

Advantage of air spray injectors ?

A

Low carbon emissions
Lower pollutants

149
Q

What is the most sensitive part of the GTE

A

The turbine assembly is most temperature and pressure sensitive part and is life critical

150
Q

What happens to turbine size heading away from heat

A

It increases

151
Q

What does the turbine drive ?

A

Compressor, front fan, accessory gearbox

152
Q

Compressor stage is ?

A

Rotating rotor
Stationary stator

153
Q

Turbine stage is made up of

A

Stationary nozzle guide vein (NGV)
Rotating turbine rotor

154
Q

What does the turbine do ?

A

Extract kinetic energy to creat rotation of turbine discs and thus the spool shaft

155
Q

Impact on T, sP, V across the turbine

A

Decreases

156
Q

How is the turbine system housed ?

A

In a divergent duct

157
Q

Impulse turbines

A

Driven by a fluid jet against the blade, rotation is only achieved through this action, causing an impulse force which drives the turbine.

158
Q

Impulse turbine nozzle and rotor setup

A

Nozzle - convergent (creates a jet flow which strikes the blades)
Rotor - constant area

159
Q

Reaction turbine

A

Is designed in the opposite to impulse and utilises newton’s 3rd law. Air accelerated through convergent ducts creating a reaction force

160
Q

Reaction turbine rotor and stator set up

A

Nozzle - constant area
Rotor - convergent shape (accelerates air through it)

161
Q

P/V/T across an impulse turbine (NGV/Rotor)

A

NGV
P- Decreases
V - Increases
T - Decreases

Rotor
P - Decreases
V - Increases
T - Decreases

162
Q

P/V/T across an Impulse/reaction turbine (NGV/Rotor)

A

NGV
P - Decrease
V - Increase
T - Decrease

Rotor
P - Decrease
V - Increase
T - Decrease

163
Q

P/V/T across a reaction turbine (NGV/Rotor)

A

NGV
P - No change
V - No change
T - No change

Rotor
P - Decrease
V - Increase
T - Decrease

164
Q

How are blades connected to discs

A

Fir tree connection, increases surface area whilst creating multiple load paths

165
Q

How is blade stress monitored ?

A

HCF - high number of small stresses (vibrations)

LCF - low number of large stresses

166
Q

How is blade stress reduced ?

A

Reducing blade temp
Single Crystal tech sees alloys moulded in a specific manor to reduce it

167
Q

Active clearance control (ACC) role ?

A

Ensures minimum loss within turbine, using hot bleed air to expand the turbine case to maintain small tip clearances.

168
Q

How is blade tip losses reduced ?

A

Shrouding

169
Q

Typical exhaust system composition

A

Jet pipe
Propelling nozzle
An exhaust cone

170
Q

Purpose of exhaust system ?

A

To maximise thrust by accelerating air rear wards

171
Q

When does the propelling nozzle become choked ?

A

When nozzle velocity reaches M1.0

172
Q

P/V/T effect in exhaust

A

P + T fall
V may increase

173
Q

How is exhaust noise reduced ?

A

Shrouding high velocity core exhaust gas with cold bypass air. Mixer units can be used instead

174
Q

What does scarfing do ?

A

Reduces noise on modern A/C

175
Q

How is reverse thrust produced ?

A

By reversing some of the hot stream with blocker doors or clamshells or buckets

176
Q

How is reverse thrust produced on high bypass engines ?

A

Reverse thrust is produced by reversing some of the bypass air through cascade vanes and doors in the nacelle

177
Q

How is inflight reverse thrust prevented ?

A

Interlocks.
Airbus won’t let reverse thrust be used at low speeds.

178
Q

Cold stream reversal is used on ?

A

Larger, high bypass engines

179
Q

Minimum number of reverse thrust protections ?

A

3
One on flight deck

(Visual indication of doors, green for in operation, Amber for unlocked)

Two operated by engine

180
Q

How are blocker doors operated ?

A

Hydraulically

181
Q

How are clamshells and buckets operated

A

Pneumatically

182
Q

How is engine temp measured?

A

Thermocouple

183
Q

Thermocouple composition?

A

Two dis-similar metals joined to form a junction with a loop, a small voltage is produced when exposed to heat

184
Q

EGT ?

A

Exhaust gas temperature

185
Q

TGT

A

Turbine gas temperature

186
Q

TET

A

Turbine engine temperature

187
Q

JPT

A

Jet pipe temperature

188
Q

How are rotating shafts supported

A

Needle roller bearings

189
Q

How are thrust loads generated by shafts transferred to the main engine casing ?

A

Ball bearings, so shafts must have both types of bearing

190
Q

How are bearings lubricated and cooled ?

A

By engine oil

191
Q

Why does the filter have a bypass ?

A

Incase it becomes blocked

192
Q

What surrounds each set of bearings

A

A bearing chamber

193
Q

Main lubrication system components are (7)

A

Oil pressure pumps
Scavenge pumps
Oil reservoir
Oil cooler/fuel heater
Filters
Magnetic chip detectors
Air/Oil separator

194
Q

Labyrinth seal use ?

A

To prevent loss of oil from bearing housing

195
Q

If you notice engine run down time has decreased, this means ?

A

There’s a damaged abradable lining/seal (grabbing abradable seal)

196
Q

Pre flight lubrication checks

A

Oil quantity check - (sight glass)
Oil leaks - (walk around)
Shortly after engine start oil pressure should rise after 30 secs. If not may indicate a leak

197
Q

What does rising oil quantity indicate ?

A

Fuel leaking into oil lube system

198
Q

How is filter blockage indicated ?

A

CLOG

199
Q

Smell of damp socks or acrid smoke may indicate ?

A

Internal engine issue

200
Q

Purpose of engine fuel system ?

A

To provide fuel to the combustor at the correct pressure under all conditions

201
Q

Fuel delivery is dependent on ?

A

Core rotation speed (N2)

202
Q

FADEC stands for

A

Full Authority Digital Engine Control

203
Q

Heart of the FADEC is a ?

A

Engine electronic controller (EEC), which has two channels for redundancy

204
Q

FADEC power supplies ?

A

FADEC alternator/ generator - in flight

A/C electrical system - below 20% of N2 before and after

205
Q

Major FADEC functions are

A

Deliver correct amount of fuel

Maintain sufficient HP pump output at low RPM

Fuel shut off when commanded

Overspeed protection

Controlling compressor airflow (BLD valves)

Ensuring manifold draining on shutdown

Reverse thrust

ACC

(Clue is F stands for Full ) Anything engine related

206
Q

If you have a single channel failure ?

A

No loss of functionality, FADEC fault would be displayed

207
Q

Dual channel failure ?

A

(Bank & PP answer is ) engine is will fail/ shutdown
( Mick says it will revert back to last selected power setting)

208
Q

Jet fuel is a form of ?

A

Kerosene or parrafin oil
Most commonly Jet A and Jet A-1
(Jet A-1 has additives)

209
Q

Jet A flash and waxing point ?

A

Flash +38°C
Waxing -40°C

210
Q

Jet A-1 flash and waxing point

A

Flash point +38°C
Waxing point -47°C

211
Q

Fuel additive blend is ?

A

Fuel system icing inhibitor (FSII)
Anti static additives
Oxidation and corrosion inhibitors

212
Q

What fuel cane be used on cold climates (Canada, the poles) ?

A

Jet B
70% gasoline
30% kerosene
(Jet B is banned in Europe for commercial operations for safety and environmental concerns)

213
Q

Fuel waxing ?

A

Fuel turns to a slushy substance and can CLOG all components within the system. Any water will for slush way before waxing point.

214
Q

How is fuel starvation prevented ?

A

Fuel heater is now placed before the filters

215
Q

De-rating means ?

A

The engine is set to have lower thrust in ideal conditions using less fuel.
However max thrust isn’t available if it becomes required

216
Q

Flex thrust is ?

A

A temporary limitation on max thrust created by entering an assumed temperature which is higher than ambient, so engine produces less thrust saving fuel.
Max thrust (TO/GA) is available if required

217
Q

How are de-rate and flex thrust set

A

By the crew via the CDU

218
Q

Thrust may be indicated by ?

A

ratio of inlet to outlet pressure (EPR) or speed of the tan (N1)

219
Q

Increase of vibration means ?

A

Trouble ahead

220
Q

2 types of engine starter motor are ?

A

Air (pneumatic) starter - driven by compressed air
Electric (starter/generator) - driven by AC to start accessory gearbox, becomes a generator at ground idle.

221
Q

Dry start

A

Low staggering RPM
No EGT
No fuel flow
- could be HPSOV malfunction

222
Q

Hung start

A

Low staggering RPM
High EGT
Low fuel flow
- could be a compressor stall
- low bleed pressure
- engine failing to reach self sustaining speed

223
Q

Hot start

A

Normal RPM increase
Rapid and excessive EGT rise
Normal fuel flow
-possible following a previous failed start attempt

224
Q

Wet start

A

Low staggering RPM
No EGT
Some indicated fuel flow
- dry run should be carried out before re-trying

225
Q

Multi engine spool start, difference in rotational speeds

A

N1- 20-25%
N2- 50-60%

226
Q

Torching may result in ?

A

A tailpipe fire
This will not illuminate any warning
It may or may not be indicated by EGT

227
Q

APU auto shutdown reasons

A

Fire warning
Excessive EGT
Low oil pressure
High oil temperature
Airspeed/Altitude limit exceeded
APU overspend
High bleed Air temperature

228
Q

Typical APU capacity limits

A

Electrical power and Air bleed - 11’000ft
Air bleed - 17’000ft

Electrical power;
60KVA- 32’000 - 41’000ft
90KVA- sea level - 32’000ft

APU start up to - 41’000ft
Battery start not available above - 25’000ft

229
Q

The APU supplies

A

Electrical and (optionally) pneumatic power

230
Q

Starting sequence for an GTE on the ground ?

A

Starter, rotation, ignition, fuel

231
Q

What is specific range in a jet aeroplane ?

A

Nautical miles flown per unit mass of fuel

232
Q

Advantages of multi-spool engines ?

A

One smaller air starter driving only one spool can be used

233
Q

In a GTE an un geared fan has the same RPM as ?

A

The low pressure compressor

234
Q

What is the energy delivered by a free turbine DEPENDANT on ?

A

Rotational speed of the HP spool

235
Q

Bypass ratio is the ratio of ?

A

Hot air mass flow to cold air mass flow

236
Q

Converging duct induces ?

A

Decrease in pressure, increase in exhaust gas velocity
(pressure into speed)

237
Q
A

ATPL Theory (7 decks)

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