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DANGER
JET
INTAKE
Centerof Gravity
AerodynamicCenter
LIFT
WEIGHT
DRAGTHRUST
High Ratio
Low Ratio
High
Low
L
AOA
C
THICKNESS-TO-CHORD RATIO
AOA
CL
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PRESSURETEMPERATURE
DENSITY
ALTITUDE
36,000 FT
LC max
LC
StallRegion
AOA
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Cdi=
(CL)2
AR
DRAG
Fixed Wing
VELOCITY (KIAS)Low
AOA
High
Total
Drag
L/DMax
Parasite Drag
Induced Drag
LowHigh
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Roll
LATERALAXIS
VERTICALAXIS
LONGITUDINALAXIS
Pitch
Yaw
CENTER OF GRAVITY
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TIMETIMEDISPLACEMENT
DISPLACEMENT
NON-OSCILLATORY OSCILLATORY
POSITIVE STATIC STABILITY
Equilibrium
Tendency to Return to Equilibrium
POSITIVE DYNAMIC STABILITY:
DISPLACEMENT
Initial Displacement
(Positive Static)(Positive Dynamic)
(Positive Static)(Positive Dynamic)D
ISPLACEMENT
TIMETIMEDISPLACEMEN
T
DISPLACEMEN
T
NON-OSCILLATORY OSCILLATORY
NEGATIVE STATIC STABILITY
Equilibrium
Tendency to Continuein Displacement Direction
NEGATIVE DYNAMIC STABILITY:
TIMETIMEDISPLACEME
NT
DISPLACEME
NT
NON-OSCILLATORY OSCILLATORY
NEUTRAL DYNAMIC STABILITY:
(Neutral Static)(Neutral Dynamic)
(Positive Static)(Neutral Dynamic)
NEUTRAL STATIC STABILITY
Equilibrium Encounteredat Any Point of Displacement
the amplitude of motion of a disturbed objectdecreases with time.
the amplitude of motion of a disturbedobject remains constant with time.
the amplitude of motion of a disturbedobject increases with time.
(Positive Static)(Negative Dynamic)
(Negative Static)(Negative Dynamic)
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STABLE
Center ofGravity
AerodynamicCenter
Pitching Moment
NEUTRAL
Center ofGravity
AerodynamicCenter
Pitching Moment
UNSTABLE
Center ofGravity
Pitching Moment
AerodynamicCenter
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WITH DIHEDRAL
Less Lift
More Lift
More Stable
WITHOUT DIHEDRAL
Destabilizing
Neutral
Stabilizing
Center ofGravity
Centerof Lift
Center
of Lift
Center ofGravity
Centerof Lift
Center ofGravity
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AerodynamicLimitNegative
+AerodynamicLimitPositive
LOADFACTORG FORCE
0
VELOCITY INCREASE
0
Stall
Stall
DAMAGE
DAMAGE
ULTIMATE STRUCTURAL LIMIT, POSITIVE
ULTIMATE STRUCTURAL LIMIT, NEGATIVE
STRUCTURAL LIMIT, POSITIVE
FAILURE
FAILURE
_
STRUCTURAL LIMIT, NEGATIVE
AeroelasticLimit
CorneringSpeed
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DIRECTION OF MOTIONAll waves generated at equal time intervals
Point Source for Pressure Waves
NO MOTION SUBSONIC SONIC (MACH 1.0)a. b. c.
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Bow Wave
SubsonicFlow
ObliqueShock
Waves
Turbulent Air(Subsonic)
Turbulent BoundaryLayer (Subsonic)
SupersonicFlow
ExpansionWave Fan
M = 1.05
Expansion Wave Fan
60
10
20
30
40
50
40200-20-40-60-80
Temperature (C)
Speed of Sound (Knots)
Temperature
Speed of SoundPressureAltitude
(1,000 Ft.)
0
570 600 630 660
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MAXIMUM LOCAL VELOCITY IS LESS THAN SONIC
MCRIT = .80 Mach for T-45
Flow Accelerates to above Flight Mach
Sonic Flow (m = 1)
FLIGHT MACH IS LESS THAN ONE
SupersonicFlow
Normal Shock Wave
Subsonic Possible Separation
Force Divergent Mach Number = 0.85 for T-45
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Normal Shock Wave
SupersonicFlow
Normal Shock Wave
Separation
Supersonic Flow
Separation
Supersonic Flow
ObliqueShock Wave
ObliqueShock Wave
Force Divergent Mach Number
VELOCITY
0.8 0.85 1.0 1.2
DRAGCOEFFICIENT
MCRIT
CD
CD
Total Drag
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Force Divergent Mach Number
VELOCITY
0.8 0.85 1.0 1.2
DRAGCOEFFICIENT
MCRIT
CD
CD
Total Drag
Supersonic Flow
Supersonic Flow
Oblique
Shock Wave
Oblique
Shock Wave
Lower
SupersonicFlow
Separation
Subsonic
Bow Wave
Supersonic Flow
Supersonic Flow
Separation
Oblique
Shock
Wave
ObliqueShock
Wave
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Compression Wave
Vortex
LiftCoefficient
Span LocationRoot Tip
TransonicLiftDistribution
SmoothLiftDistribution
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HIGH THICKNESS - TO - CHORD RATIO
LOW THICKNESS - TO - CHORD RATIO
Wing Horizontal Tail
IncreasedDownwash
WingHorizontal Tail
Vortex
ResultantFlow
TypicalFlow
T/C RATIO
1:2
T/C RATIO
1:1
5 5
510
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0 1.0 2.0 3.0
0
30
45
60
MACH NUMBER, M
DRAGCOEFFICIENT
CD
SWEEP ANGLE,
C
SWEPT WING
STRAIGHT WING SWEPT WING
Flow OverWing
Spanwise Flow
Flow Producing Lift
DP
V
STRAIGHT WING
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Separation
Ineffective
Effective
Effective
Ineffective
Separation
Separation
IneffectiveEffective
Effective Ineffective
Separation
No direct feedback between the stick andcontrol surface. Stick input ports hydraulic fluidto the actuator effecting control surface
Control stick "feel" is artificial.
IRREVERSIBLE(NO FEEDBACK FROM CONTROL SURFACES)
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Direct mechanical connection between
rudder pedals and control surface.
NO HYDRAULIC ASSIST TO CONTROL INPUTS.
FEEDBACK PROVIDED BY DIRECT LINKAGE.
SupersonicAirflow
NormalShock
Wave
ObliqueShock
Wave
SlowerSupersonic Subsonic Engine
ENGINE INLET
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30
VORTEX GENERATOR
SIDE VIEW
NOTE: All Dimensions in mm51.
17.
CL
12 3 4 5 6 7 8 9
10
11
12
13
14
15
16
17
18
19
PLANFORM VIEWNot To Scale
BL 2120.
BL 2408.
BL 4052.
BL 4589.5
144.
137.
107.5
10
25%CHORD
BL 4698.
20
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With Stabilization Strips
Added to Tail and Rudder
Bow Wave
StabilizedShock Wave
Stabilized
Shock Wave
Rudder
Without Stabilization Strips
Bow Wave
MovingShock Wave
Rudder
MovingShock Wave
0.20"
0.70"
Cross Section ofRudder Shock
Stabilization Strip
VERTICAL FIN
PLANFORM VIEW
50% Chord
Rudder Shock
Stabilization Strips
2.0"
AS SHOCK WAVE APPEARS,AERODYNAMIC CENTER MOVES AFT
Shock Wave
Center ofGravity
Aerodynamic Center
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SmoothLiftDistribution
LiftCoefficient
Root Span Location Tip
TransonicLiftDistribution
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+
+Stall Point
Stall Develops
Stall Begins Deep Stall
Straight Wing
Swept Wing
AOA0
LIFT
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Unstable
Region of Stall
Center of Pressure
Center of Gravity
Aerodynamic Center
Slat Leading Edge
Stall Strip
WUSS Stall Strip
AIRFLOW
Stall Strip
Leading Edge
of Main Wing
Slat Leading Edge
Stall Strip
Slat Leading Edge
WUS
S
Slat
WING
WUSS Stall Strip
Wing Leading Edge
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3 1/2
CL
ConstantIncidence
Wing
AOA in Degrees
ROOT
TIP
CL
Tip WithoutGeometric Twist
Root WithoutStall Strips
AOA
CL
AOA
Root WithStall Strips
Tip WithGeometric Twist
Adding Stall Strips tothe Root Causes theRoot to Stall Earlier (Ata Lower AOA)
Adding GeometricTwist Causes the Tip toStall Later (At a HigherAOA)
3 1/2
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CL
WING
WINGWITHFLAP
S
AOA in Degrees
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STABILATORVANE
(CL) max
(CL) max
STRAIGHTWING
SWEPTWING
(CL)
Coefficientof Lift
Angle Of Attack (AOA)
CL
AIRFLOWAOA in Degrees
DOWNWASH
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ARTIFICIAL STALL
WARNINGSTALL BUFFET STALL
NOTE: All Speeds Are KIAS Above Stall Speed
CLEAN
APPROACH
21.5 Units / 10 KIAS 25 Units / 1-2 KIAS 26 Units / 0 KIAS
29-30 Units / 0 KIAS28 Units / 1 KIAS21.5 Units / 10 KIAS
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PHASE COCKPIT INDICATIONS
Normal FlightENTRYINPUT
RECOVER
Y
AOA above stallREDUCE
STICK FORCESTALL
DEPARTUREAircraft no longer responds tocontrol inputs
NEUTRAL
CONTROLS
INDUCED YAW
POST - STALLGYRATIONS
AOA turn needle,and airspeed oscillation
NEUTRAL
CONTROLS
INCIPIENT
SPIN
AOA and turn needle
pegged; airspeed oscillation ANTI - SPIN
CONTROLSAOA and turn needlepegged; airspeed steady oroscillating slightly
STEADY -STATESPIN
SUSTAINED YAW
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RUDDER
AIRFLOW
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45-DEGREE TRUE AOA SPIN INDICATIONS30-DEGREE TRUE AOA SPIN INDICATIONS
28 Units or More AOA
Positive G
Turn Needle in Direction of Spin
180 KIAS
1,200 Feet / Turn
10 Turns / Minute
30 Units AOA
Positive G
Turn Needle in Direction of Spin
100 to 110 KIAS
1,000 Feet / Turn
15 Turns / Minute30
45
45
60
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Altitude Loss Per Turn 1,000 ft
Airspeed 50 to 120 kts
15 - 20 Turns / Minute
-60AOA
-30 Pitch-60AOA Spin
-40AOA Spin-50Pitch
Airspeed 100 - 160 kts
15 - 20 Turns / Minute
Altitude Loss Per Turn 1,000 ft
-40AOA
-25AOA Spin
-65Pitch
Airspeed 140 - 200 kts
10 Turns / Minute
Altitude Loss Per Turn 1,100 ft
0 Units AOA
Negative G
Turn Needle in Direction of Spin
Steady State IAS
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PHASE COCKPIT INDICATIONS
Normal FlightENTRYINPUT
R
ECOVERY
AOA above stallREDUCE
STICK FORCESTALL
DEPARTURE Aircraft no longer responds tocontrol inputs
NEUTRAL
CONTROLS
INDUCED YAW
POST - STALLGYRATIONS
AOA turn needle,and airspeed oscillation
NEUTRAL
CONTROLS
INCIPIENTSPIN
AOA and turn needlepegged; airspeed oscillation ANTI - SPIN
CONTROLSAOA and turn needlepegged; airspeed steady oroscillating slightly
STEADY -STATESPIN
SUSTAINED YAW
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30
1010
20
0ANGL
E
OFATT
ACK
OFF
WHEELS
Transmitter ProbeCarrierApproachLights
AOA Indexer
AOA Indicator
ADIDisplay
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T- 45A T- 45C
Digital AOA
AOA Bracket
Waterline
Digital AOA
AOA Bracket
Velocity Vector
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AN AIRCRAFT MUST POSSESS ADEQUATE
STABILITY TO MAINTAIN A FLIGHT PATH
AND
BE MANEUVERABLE ENOUGH TO
ACCOMPLISH ITS MISSION
CONTROL STABILITY
CONTROLLABILITY AND STABILITY
ARE A TRADEOFF
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13,500
13,000
12,500
12,000
11,500
11,000
10,500
10,000
9 11 13 15 17 19 21 23 25
AftGearUp
AftGearDown
Upper
FuselageFuel
LowerFuselage
Fuel
OuterWing
Fuel
CenterWingFuel
Forward
Limit
2Crew
Mem
bers
GearUp
GearDown
(less
than
0.8
Mac
h)
C. G. - %M.A.C.
AIRCRAFTWEIGHT(LBS.)
Mean
AerodynamicChord
AERODYNAMIC CENTER
CENTER OF PRESSURE
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STABILATORVANE
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Yawing Moment AboutDownwind Gear
Less Drag
WIND
More Drag
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ExhaustCombustion
Section
VinorV1
VexhorV2
Compressor
Section
Turbine
N1Compressor
N
Compressor2 NN 2 1
Turbines
Section
Exhaust
Section
AfterburnerCombustion
Section
VariableExhaust
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N1Compressor
N
Compressor2
Fan(Outboard)
Combustion
Section
NN
21
Turbines
Section
Exhaust
AirCombustionand Exhaust
Bypass Duct
Bypass Duct
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20 30 40 50 60 70 80 90 100
20
40
55
75
90
100
% RPM
%T
hrustAvailable
T-45
Theoretical
SEA LEVEL STANDARD DAY
JET ENGINE RPM THRUSTVS.
100
100
99
97
95
84
90
69
80
46
70
29
% of MAXRPM
% of MAXTHRUST
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0 100 200 300 400 500 600 700 800
5,200
5,400
5,600
5,800
6,000
Calibrated Airspeed - Knots
Thrust(lbs.)
5,000
Actual
Theoretical
Ta= Q (V2- V1)
AIRSPEED
THRUST
Ta
V2- V1EFFECT
RAM EFFECT (Q)
ALTI
TUDE
0.4 0.6 0.8 1.0SEALEVEL
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
THRUST
DENSITY
TROPOPAUSE
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THRUST
KTAS
T SEA LEVEL
T FL 350
SEA LEVEL
FL 350
r
r
Vmr
Vmr
30 40 50 60 70 80 90 100 110
1,000
2,000
3,000
4,000
5,000
% RPM
Thrust(lbs.)
- 42F. Day
Standard Day
0
105F. Day
6,000
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(L/D)MAX
0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
ThrustorDrag(lbs.)
0
6,000
200 300 400 500 600
DT= Tr
SEA LEVEL
STANDARD DAY
(CLEAN)
(L/D)MAX
0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thrus
t(lbs.)
0
6,000
200 300 400 500 600
SEA LEVELSTANDARD DAY
(CLEAN)
VMR
Tr
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(L/D)MAX
0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thrust(lbs.)
0
6,000
200 300 400 500 600
T
SEA LEVEL
STANDARD DAY(CLEAN)
T at Sea Level
VH
a
r
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thrust(lbs.)
0
6,000
Region ofNormal
Command
Total Drag
Region ofReverse
Command Tr
(L/D)MAX
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0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thru
st(lbs.)
0
6,000
200 300 400 500 600
at Sea Level
10,000 LBS.
12,000 LBS.
(L/D)MAX
aT
0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thrus
t(lbs.)
0
6,000
200 300 400 500 600
-SL
T at Sea Level
VMRFL 350
TrTr
a
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0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thrus
t(lbs.)
0
6,000
200 300 400 500 600
at Sea Level
TrHIGHER DRAG
(L/D)MAX
TrLOW DRAG
aT
0 100
1,000
2,000
3,000
4,000
5,000
TRUE AIRSPEED - KNOTS
Thrus
t(lbs.)
0
6,000
200 300 400 500 600
at Sea Level
14 units
23 unitsCLEAN
APPROACHCONFIGURATION
17 units
aT
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