Atpl - Jet Engine

Front 1

Thrust basic formula

Back 1

F=M x a(m/s2)

Front 2

newtons 3rd Law

Back 2

every action >> Equal and opposite reaction.

Front 3

Jet thrust Vs. RPM/Alt ?

Back 3

Prop to RPM
I-Prop to Alt

Front 4

Low Bypass?
Hi Bypass?
(mass Vs. accel.)

Back 4

Low >> Small mass @ Hi Vel.
Hi >> Large mass @ Low Vel.

Front 5

Turbo Shaft:
Power through ..... .

Back 5

Shaft

Front 6

Critical Engine

Back 6

-Shortest thrust vector arm
-Dn going blade: more thrust

Front 7

Combustion cycle @ Jet engine.
name?
at constant .....?

Back 7

Brayton cycle
Pressure

Front 8

Supersonic intakes:
need to reduce .... by .... or .... .

Back 8

Airflow Vel
Variable throat
Spill valve

Front 9

Unheated compressed air @ T.Fan eng >> ... % as Bypass

Back 9

80%

Front 10

Bypass engine advantages(3)

Back 10

1. Better Propulsive efficiency.
2. Better SFC
3. Better Th/Wt ratio.

Front 11

Jet engine Fan construction

Back 11

Titanium Alloys >> solid / Hollow(HC)

Carbon reinforced epoxies >> Lighter.

Front 12

Wide cord fan design:
3 feature

Back 12

Single row of blades
No inlet guide vanes
No mid shroud

Front 13

Mid blade support @ jet Fan?

Back 13

prevents:
Flapping or Bending

Front 14

Shingling @ Jet Fan?

Back 14

Overlapping fan blades
Reduces For'n obj dmg.

Front 15

Compressor Ratio

Back 15

Change of air Px btw inlet/outlet

Front 16

Centrifugal Comp.
comp. raio ... to...

Back 16

4.5 to 1

Front 17

Centrifugal Comp.
large ... area.
low ............

Back 17

frontal

air mass flow

Front 18

Centrifugal Comp.
better @ ... speed.
better ..... presentation carac's

Back 18

low

ingestion/stall/ surge/

Front 19

Axial Flow Comp.
Cold End?
Hot End?

Back 19

C >> Nickel alloys
H >> Titanium alloys

Front 20

Compressor Airflow Control
4 ways?

Back 20

1. Inlet Guide Vanes
2. Variable Geometry Guid Vanes
3. Turbine Blade Angle (stagger/setting angle)
4. Engine Bleed Valve

Front 21

Inlet Guide Vanes:
Direct air to .... @ ...
Sensitive to ...

Back 21

first row
correct angle

engine speed

Front 22

Variable Geometry Guide Vanes:
also called ........
provide max efficiency @ ......

Back 22

Variable angle stator

Wide range of engine speeds

Front 23

Variable Geometry Guide Vanes:
Powered by : ..... / .....

Back 23

Fuel flow
Hydro mechanical

Front 24

Turbine Blade angle
also called ......./...... angle

Back 24

stagger
setting
(change root to tip)

Front 25

Bleed Air @ jet engine
From ..... @ ..... stages @ ....PSI

Back 25

Hi Px compressor
Intermediate/late
40-60

Front 26

Bleed Air Valve @ jet engine
Provides ....
Controls ....

Back 26

Bleed Air
Px btw compressor stages

Front 27

Bleed Air Valve @ jet engine
effect on Thrust/EPR/Temp?

Back 27

Thrust >> dec
EPR >> dec
Temp >> inc

Front 28

Bleed Air Valve @ jet engine
Open @ .... and Close @ ....

Back 28

Low px
Hi px

Front 29

Compressor stall:
Affects only .......

Back 29

One or two stages

Front 30

Compressor Surge:
Affects ......
Is due to ...../...../.....

Back 30

All stages.
Abrupt maneuver /ex fuel/ accel

Front 31

Compressor Surge indications?
(4)

Back 31

Loss of thrust
Fluctuating RPM
Banging
EGT rise

Front 32

Stall/ Surge protection

Back 32

VIGVs
Multi spool comp
Bld Valv (@early stages)

Front 33

Can Annular combustor
No .... and ....
disadvantage?

Back 33

individual casing
ignitors

Large % of air >> for cooling

Front 34

Diffuser @ jet combustor
What @ How?

Back 34

prepare air for entry
stable flame >> effective combustion
by reducing compressed air

Front 35

Dilution Holes @ jet combustor
What?

Back 35

Reduce temp at combustion chamber

Front 36

Swirler @ jet combustor
What and How?

Back 36

Rapidly mixes air and fuel
By turbulance

Front 37

Fuel injector principles:
Atomizer

Back 37

Swirl

Cone shaped tiny droplets

Front 38

Fuel injector principles:
Vaporizer

Back 38

Preheating >> complete burn

Front 39

Fuel injector principles:
Air spray

Back 39

Air/fuel mix @ nozzel

Front 40

Fuel injector principles:
Duplex

Back 40

two orifices
Prim >> small
Main >> Large (spring loaded)

Wide Px rang

Front 41

Fuel injector principles:
Spill type

Back 41

Hi Px fuel @ all times

Front 42

Fuel injector principles:
Rotating

Back 42

Atomizing by centrifugal action

Front 43

Fuel injector principles:
Spray advantage ?

Back 43

Reduces CO2 and smoke

Front 44

Ignitor @ jet combustor
Principle?
Types?

Back 44

*Capacitor discharge

Constraint/constricted
Shunted

Front 45

Turbine Blade types:
1 .... >> ..........
2 .... >> ..........

Back 45

Impulse >> purely air impact
Reaction >> air impact + convergency of adj blade.

Front 46

Turbine blade temp control

Back 46

Hi Px comp air throw tiny holes

Front 47

Nozzle Guide Vanes (NGVs):
3 jobs:

Back 47

*Accel airflow
*Directs air @ most eff AOA to turbine
*cools air before hitting

Front 48

To ensure Uniform velocity across turbine blade.

Back 48

Turbine Blade twist.
inc root to tip

Front 49

Elongation of turbine blades

Back 49

Creep
(permanent)

Front 50

To prevent gap gas losses btw turbine tip and casing

Back 50

Shrouds

Front 51

Active Clearance Control
Job and how

Back 51

Improv efficiency and reduce EGT

By optimum Clrnce throughout engine operation profile

Front 52

Active Clearance Control
Methodes:(3)

Back 52

1.Pneumatic >> Casing exp control by comp air
2.Mechanical >> longer blade
3.Thermal

Front 53

Device at jet exhaust
reduces noise by ....

Back 53

Mixer unit
by mixing hot and cold air

Front 54

How to restore airflow energy at exhaust?

Back 54

Using convergent nozzle to inc velocity

Front 55

Supersonic Nozzles ?

Back 55

Div. Conv nozzles
super / sub sonic

Front 56

Reverse Thrust
Most eff at ....

Back 56

Hi speeds > above 80 notes

Front 57

Reverse Thrust
not below 60-80 kts
cus?

Back 57

FOD >> own ingestion
affect other engines intake
FWD vis reduces

Front 58

Reverse Thrust
type 1

Back 58

Hot Stream Reversing
Buckets/ Clamshell doors
Deflect Hot Exhaust fwd

Front 59

Reverse Thrust
type 2

Back 59

cold stream
for under wing/ Hi Bypass
translating cowl
redirecting fan air

Front 60

Free Turbine
also called ...
Prop driven by ...
no connection btw .... and ....

Back 60

Power turbine
Exhaust Gas from Gas Generator
turb and comp

Front 61

Multi spool eng:
2 advantages

Back 61

Each comp @ optimum RPM
Lower Start Trq

Front 62

Jet noise reason?

Back 62

Exh gas velocity >> shear effect

Front 63

Jet noise reducton:

Back 63

Radial mounted nozzles
Corrugated Perimeter nozzles
Hi bypass
Reduced T.O. thrust
Min noise departure operation(Vx)

Front 64

Radial mounted nozzles
Princ of op

Back 64

inc frq
larg Vel >> smaller streams
easier to disparage

Front 65

Major jet noise @ approach

Back 65

Airframe & Fan

Front 66

Major jet noise @ T.O.

Back 66

Jet Mixing & Fan

Front 67

Prop noise reduction

Back 67

More Blades!

Front 68

To restore T.O. power at low density

Back 68

adding water or water/methane mix at combustor inlet.

Front 69

Reduced power T.O.
also called

Back 69

- D rated thrust
- Graduated power T.O.

Front 70

Assumed/Flexible Temperature?

Back 70

- Higher than actual
- Actual t.o wt.

Front 71

Reduced power T.O.
Max allowable reduction

Back 71

25%

Front 72

Reduced power T.O.
Not used at(4)

Back 72

- Comtam. RWY
- no antiskid
- no RR
- increased V2 proc

Front 73

Engine Starting
Air Turbine Starter?

Back 73

Bleed air form APU
to drive turbine

Front 74

Engine Starting
Starter Generator ?

Back 74

Hi Trq DC motor
Thro reduction gearbox

Front 75

Jet Relight altitude limitation?

Back 75

Too hi
Too slow
>> insuf accel/O2

Front 76

Auto ignition : operated at ?

Back 76

Hvy Rn / Svr Turb

Front 77

In flight Jet start with no starter?

Back 77

Wind milling star

Front 78

Jet Hot start:
Due to ....
Indications ...
Whats happening ......

Back 78

-Fuel ig too early
-EGT rises pass MAX
-Achieved s.sust spd but unstable combustion

Front 79

Jet Hot start:
Action?

Back 79

Dry motor the engine to cool dn.

Front 80

Wet start:
Due to ...
What will happen ...

Back 80

No light up
Ex fuel at chamber

Front 81

What is Hung Start?

Back 81

Eng lights up
But no accel to S.sust spd

Front 82

Hung start Indications?(2)

Back 82

No EGT rise
RPM stab @ starter speed.

Front 83

Hung start reasons?(4)

Back 83

Hot and Hi
Low starter RPM
Early starter cut out
Strong T.wing

Front 84

Eng fire at or aft star:
Action?

Back 84

shut off fuel and ig
motor with starter > cool dn

Front 85

Fuel Dipper?

Back 85

Rapidly reduce fuel flow
@ Over Temp warning
replace by FADEC

Front 86

Spill Valve?

Back 86

Fuel Pump Control
By varying F.pump servo Px
replace by FADEC

Front 87

Most propulsive efficiency at?

Back 87

Hi Alt
Hi RPM
Hi Airspeed

Front 88

Most efficient RPM .... %

Back 88

85 to 95

Front 89

SFC formula

Back 89

Fuel flow
to
Thrust

Front 90

Best SFC at ?

Back 90

Hi RPM (dsn)
Low Temp (hi alt)

Front 91

Max Endurance :
best ..... @ min ..........

Back 91

SFC
Power Req'ed

Front 92

What is POD NOT?
Where?
Reason?

Back 92

Tilted Down Engine
At Hi alt
To reduce fuel burn

Front 93

flat rated temp means?

Back 93

engine > capable of higher operating temp, but in this installation the allowed temp is limited to maintain the flat rating.