Peter J. Swatton 
Principles of Flight for Pilots [EPUB ebook] 

Series Preface xxi

Preface xxiii

Acknowledgements xxv

List of Abbreviations xxvii

Weight and Mass xxxi

Part 1 The Preliminaries 1

1 Basic Principles 3

1.1 The Atmosphere 3

1.2 The Composition of Air 3

1.2.1 The Measurement of Temperature 3

1.2.2 Air Density 4

1.3 The International Standard Atmosphere 4

1.3.1 ISA Deviation 5

1.3.2 JSA Deviation 5

1.3.3 Height and Altitude 6

1.3.4 Pressure Altitude 7

1.3.5 Density Altitude 7

1.4 The Physical Properties of Air 7

1.4.1 Fluid Pressure 7

1.4.2 Static Pressure 7

1.4.3 Dynamic Pressure 7

1.5 Newton’s Laws of Motion 8

1.5.1 Definitions 8

1.5.2 First Law 8

1.5.3 Second Law 8

1.5.4 Third Law 9

1.6 Constant-Acceleration Formulae 9

1.7 The Equation of Impulse 9

1.8 The Basic Gas Laws 10

1.8.1 Boyles Law 10

1.8.2 Charles’ Law 10

1.8.3 Pressure Law 10

1.8.4 The Ideal Gas Equation 10

1.9 The Conservation Laws 11

1.10 Bernoulli’s Theorem 11

1.10.1 Viscosity 11

1.11 The Equation of Continuity 12

1.12 Reynolds Number 12

1.12.1 Critical Reynolds Number (Recrit) 13

1.13 Units of Measurement 13

Self-Assessment Exercise 1 15

2 Basic Aerodynamic Definitions 19

2.1 Aerofoil Profile 19

2.2 Aerofoil Attitude 20

2.3 Wing Shape 21

2.4 Wing Loading 23

2.5 Weight and Mass 24

2.5.1 The Newton 24

2.6 Airspeeds 24

2.6.1 Airspeed Indicator Reading (ASIR) 24

2.6.2 Indicated Airspeed (IAS) 25

2.6.3 Calibrated Airspeed (CAS) 25

2.6.4 Rectified Airspeed (RAS) 25

2.6.5 Equivalent Airspeed (EAS) 25

2.6.6 True Airspeed (TAS) 25

2.6.7 Mach Number 26

2.7 Speed Summary 26

2.8 The Effect of Altitude on Airspeeds 27

2.8.1 a. Below the Tropopause 27

2.8.2 b. Above the Tropopause 27

Self-Assessment Exercise 2 29

Part 2 Basic Aerodynamics 33

3 Basic Control 35

3.1 Aeroplane Axes and Planes of Rotation 35

3.1.1 The Longitudinal or Roll Axis 35

3.1.2 The Lateral or Pitch Axis 35

3.1.3 The Normal or Yaw Axis 35

3.2 The Flight Controls 35

3.3 The Elevators 37

3.4 Pitch Control 37

3.4.1 Control Surface Area 38

3.4.1.1 Control Surface Angular Deflection 38

3.4.2 The Moment Arm 38

3.4.3 Angle of Attack 38

3.5 Alternative Pitch Controls 39

3.5.1 Variable Incidence Tailplane 39

3.5.2 The Stabilator 40

3.5.3 The Elevons 40

3.6 The Rudder 40

3.7 Yaw Control 41

3.7.1 Control-Surface Area 41

3.7.1.1 Control-Surface Deflection 41

3.7.2 The Moment Arm 41

3.7.2.1 Engine-Induced Yaw 41

3.8 Asymmetric Engine Yawing Moment 42

3.8.1 Critical Power Unit 42

3.9 Asymmetric Rolling Moment 43

3.10 Minimum Control Speeds 44

3.10.0.1 For Take-off 44

3.10.0.2 For Landing 44

3.10.1 VMC 44

3.10.2 VMCG 44

3.10.2.1 The Effect of the Variables on VMCG and VMC 45

3.10.3 VMCL 45

3.10.4 VMCL(1out) 45

3.10.5 VMCL-2 46

3.10.5.1 The Effect of the Variables on VMCL 46

3.11 The Ailerons 46

3.12 Roll Control 46

3.12.1 The Flaperon 47

3.13 Wing Twist 47

3.14 Geometric Twist 47

3.15 Aerodynamic Twist 47

3.15.1 Twisterons 48

3.16 High-Speed Twist 49

3.16.1 Low-Speed Ailerons 49

3.16.2 High-Speed Ailerons 49

3.16.3 Roll Spoilers 50

Self-Assessment Exercise 3 51

4 Lift Generation 55

4.1 Turbulent Flow 55

4.2 Streamline Flow 55

4.3 The Boundary Layer 57

4.4 The Laminar Boundary Layer 58

4.4.1 The Transition Point 58

4.5 The Turbulent Boundary Layer 58

4.5.1 Leading-Edge Separation 59

4.6 Boundary-Layer Control 59

4.6.1 Blowing 59

4.6.2 Suction 60

4.6.3 Vortex Generators 60

4.7 Two-Dimensional Flow 61

4.8 The Stagnation Point 61

4.8.1 Aerofoil Upper-Surface Airflow 61

4.8.2 Aerofoil Lower-Surface Airflow 61

4.9 Lift Production 62

4.9.1 Symmetrical Aerofoils 62

4.9.2 Cambered Aerofoils 62

4.9.2.1 a. Negative Angles of Attack 64

4.9.2.2 b. Small Positive Angles of Attack 64

4.9.2.3 c. Large Positive Angles of Attack 64

4.10 The Centre of Pressure (CP) 64

4.11 Pitching Moments 65

4.12 The Aerodynamic Centre 67

4.13 Three-Dimensional Flow 68

4.14 Wing-Tip Vortices 68

4.15 Wake Turbulence 70

4.16 Spanwise Lift Distribution 70

4.16.1 The Effect of Wing Planform 70

Self-Assessment Exercise 4 75

Part 3 Level-Flight Aerodynamics 79

5 Lift Analysis 81

5.1 The Four Forces 81

5.2 Mass 81

5.3 Lift Analysis 82

5.4 The Factors Affecting CL 84

5.5 The Effect of Angle of Attack 84

5.6 The Effect of the Wing Shape 85

5.6.1 The Effect of Leading-Edge Radius 86

5.6.2 The Effect of Camber 86

5.6.3 The Effect of Aspect Ratio 87

5.6.4 The Wing Planform 88

5.6.4.1 The Effect of Sweepback 88

5.7 The Effect of Airframe-Surface Condition 89

5.8 The Effect of Reynolds Number 91

5.9 The Relationship between Speeds, Angles of Attack and CL 92

5.10 Aerofoil Profiles 93

5.10.1 High-Lift Aerofoils 93

5.10.2 General-Purpose Aerofoils 94

5.10.3 High-Speed Aerofoils 94

Self-Assessment Exercise 5 95

6 Lift Augmentation 99

6.1 Wing Loading 99

6.2 CLmax Augmentation 99

6.3 Slats 100

6.3.1 Automatic Slats 101

6.3.2 Manual Slats 103

6.4 Slots 103

6.5 Leading-Edge Flaps 103

6.5.1 The Krueger Flap 105

6.5.2 The Drooped Leading Edge 106

6.6 Trailing-Edge Flaps 106

6.6.1 The Plain Trailing-Edge Flap 107

6.6.2 The Split Trailing-Edge Flap 108

6.6.3 The Slotted Trailing-Edge Flap 108

6.6.4 The Fowler Flap 109

6.6.4.1 The Effect of Trailing-Edge Flaps 110

6.6.5 Leading- and Trailing-Edge Combinations 110

6.6.5.1 The Effect of Sweepback on Flap 112

Self-Assessment Exercise 6 113

7 Drag 119

7.1 Parasite (Profile) Drag 119

7.2 Surface-Friction Drag 120

7.2.0.1 Surface Area 120

7.2.0.2 Coefficient of Viscosity 120

7.2.0.3 Rate of Change of Airspeed 120

7.2.1 Flow Transition 120

7.2.1.1 Surface Condition 121

7.2.1.2 Speed and Size 121

7.2.1.3 Adverse Pressure Gradient 121

7.3 Form (Pressure) Drag 121

7.3.1 Interference Drag 122

7.4 Induced Drag 122

7.4.1 The Effect of Speed 123

7.4.2 The Effect of Mass 125

7.4.3 The Effect of Planform 125

7.4.4 The Effect of Sweepback 125

7.4.5 The Effect of Aspect Ratio 126

7.4.6 The Effect of Flap 126

7.4.7 The Effect of the CG Position 126

7.4.8 Effects Summary 127

7.5 Ground Effect 127

7.6 Wing-Tip Design 128

7.7 Wingspan Loading 129

7.8 The Coefficient of Induced Drag (CDI) 129

7.9 Total Drag 130

7.10 Analysis of the Total-Drag Curve 130

7.11 The Velocity of Minimum Drag (VIMD) 130

7.12 The Velocity of Minimum Power (VIMP) 132

7.13 The Maximum EAS/Drag Ratio (VI/Dmax) Speed 132

7.14 Speed Stability and Instability 133

7.15 The Effect of the Variables on Total Drag 134

7.15.1 The Effect of Altitude 134

7.15.2 The Effect of Mass 134

7.15.3 The Effect of Flap 134

7.16 The CL v CD Polar Diagram 136

7.17 Analysis of the Lift/Drag Ratio 137

7.17.1 The Effect of Flap 138

7.17.2 The Effect of Aspect Ratio 138

7.17.3 The Effect of Mass 139

7.18 Drag Augmentation 139

7.19 Airbrakes 139

7.20 Spoilers 139

7.20.1 Flight Spoilers 139

7.20.2 Ground Spoilers 140

7.20.3 Roll Spoilers 141

7.21 Barn-Door Flaps 142

7.22 Drag Parachutes 142

Self-Assessment Exercise 7 143

8 Stalling 153

8.0.1 The Stall 153

8.1 The Boundary Layer 153

8.2 Boundary-Layer Separation 154

8.2.1 Trailing-Edge Separation 154

8.2.2 Leading-Edge Separation 155

8.3 The Low-Speed Stalling Angle 156

8.4 Factors Affecting the Low-Speed Stalling Angle 156

8.4.1 Slat/Flap Setting 156

8.4.2 Ice Accretion 157

8.4.3 Effect on Take-off and Landing 158

8.4.3.1 Take-Off 158

8.4.3.2 Landing 158

8.4.3.3 Reduced Stalling Angle 159

8.4.3.4 Abnormal Stalling Characteristics 159

8.4.4 Heavy Rain 159

8.5 The Effect of Wing Design on the Low-Speed Stall 159

8.5.1 Swept Wings 160

8.5.2 Elliptical Wings 161

8.5.3 Rectangular Wings 161

8.5.4 Straight Tapered Wings 161

8.6 Spanwise-Flow Attenuation Devices 161

8.6.1 The Wing Fence 162

8.6.2 The Sawtooth Leading Edge 162

8.6.3 The Notched Leading Edge 162

8.6.4 Vortex Generators 162

8.7 Wing-Tip Stalling 164

8.7.1 The Effect of Flap 164

8.7.2 The Prevention of Wing-Tip Stalling 165

8.7.2.1 a. Washout 165

8.7.2.2 b. Root Spoiler 165

8.7.2.3 c. Changing Camber 165

8.7.2.4 d. Slats and Slots 165

8.7.2.5 e. Aspect Ratio 165

8.8 Stalling Characteristics 165

8.8.1 Ideal Stalling Characteristics 165

8.8.2 Swept-Wing Stalling Characteristics 166

8.9 Summary of Factors Affecting the Stalling Angle 166

8.10 Aerodynamic Stall Warning 166

8.11 Mechanical Stall Warning 167

8.11.1 The Flapper Switch 167

8.11.2 The Angle of Attack Sensor 167

8.11.3 Stick Shakers 168

8.11.4 Stick Pushers 168

8.12 Stalling Speed 168

8.13 Factors Affecting Stalling Speed 169

8.14 Centre of Gravity (CG) 169

8.14.1 Forward CG 169

8.14.1.1 Disadvantage 169

8.14.1.2 Advantage 169

8.14.2 Aft CG 169

8.14.2.1 Disadvantage 170

8.14.2.2 Advantage 170

8.15 Mass 170

8.16 Altitude 171

8.17 Configuration 171

8.18 Ice Accretion 171

8.19 Wing Planform 172

8.20 Summary of Factor Effects on Stalling Speed 172

8.21 The Speed Boundary 172

8.22 The Effect of a Gust on the Load Factor 173

8.23 Turn Stalling Speed 174

8.24 Stalling-Speed Definitions 174

8.24.1 VCLmax 175

8.24.2 VMS 175

8.24.3 VMS0 175

8.24.4 VMS1 175

8.24.5 VS 176

8.24.6 VS0 176

8.24.7 VS1 176

8.24.8 VS1g 176

8.24.9 VSR 176

8.24.10 VSR0 176

8.24.11 VSR1 176

8.25 The Deep Stall 177

8.26 The Accelerated Stall 177

8.27 The Power-On Stall 177

8.28 The Shock Stall 178

8.29 Stall Recovery 178

8.29.1 The Low-speed Stall 178

8.29.2 The Deep Stall 178

8.29.3 The Accelerated Stall 178

8.29.4 The Power-On Stall 179

8.29.5 The Shock Stall 179

8.30 The Spin 179

Self-Assessment Exercise 8 181

9 Thrust and Power in Level Flight 189

9.1 Thrust 189

9.2 Analysis of the Thrust Curves 189

9.2.1 Thrust Available 189

9.2.2 Thrust Required 190

9.2.2.1 Maximum Speed (EAS) 190

9.3 The Effect of the Variables on Thrust 191

9.3.1 Altitude 191

9.3.2 Mass 193

9.3.3 Asymmetric Flight 193

9.3.4 Centre of Gravity 195

9.4 Power 196

9.5 Analysis of the Power Curves 196

9.5.1 Maximum TAS 197

9.5.2 VMP and VMD 197

9.6 The Effect of the Variables on Power 198

9.6.1 Altitude 198

9.6.2 Mass 200

9.7 Summary 201

Self-Assessment Exercise 9 203

10 Advanced Control 207

10.1 Wing Torsion and Flexing 207

10.2 Wing Flutter 207

10.3 Torsional Flexural Flutter 207

10.4 Aileron Flutter 210

10.4.1 Torsional Aileron Flutter 210

10.4.2 Flexural Aileron Flutter 211

10.4.2.1 The Mass Balance 212

10.5 Divergence 213

10.6 Control Secondary Effects 213

10.7 Adverse Yaw 213

10.8 Counteraction Devices 214

10.8.1 Rudder/Aileron Coupling 214

10.8.2 Slot/Aileron Coupling 214

10.8.3 Spoiler/Aileron Coupling 214

10.8.4 Differential Aileron Deflection 214

10.8.5 Frise Ailerons 214

10.9 Control-Surface Operation 215

10.10 Aerodynamic Balance Methods 216

10.10.1 The Hinge Balance 216

10.10.2 The Horn Balance 216

10.10.3 The Internal Balance 217

10.10.4 The Balance Tab 217

10.10.5 The Antibalance Tab 218

10.10.6 The Spring Tab 218

10.10.7 The Servo Tab 220

10.11 Primary Control-Surface Trimming 221

10.11.1 Variable Trim Tabs 222

10.11.2 Fixed Trim Tabs 222

10.11.3 Stabilizer Trim Setting 222

10.12 Powered Controls 223

10.13 Power-Assisted Controls 223

10.14 Fully Powered Controls 223

10.14.1 Artificial Feel 224

10.14.1.1 The Simple System 224

10.14.1.2 The Servo-Assisted Hydraulic System 224

10.15 Fly-by-Wire 225

Self-Assessment Exercise 10 227

Part 4 Stability 231

11 Static Stability 233

11.1 Static Stability 233

11.2 The Effect of the Variables on Static Stability 235

11.3 Directional Static Stability 235

11.4 Yaw and Sideslip 235

11.5 The Directional Restoring Moment 235

11.5.1 Fin and Rudder Design 237

11.5.2 The Dorsal Fin 237

11.5.3 The Ventral Fin 237

11.5.4 The Moment Arm 237

11.6 Aeroplane Design Features Affecting Directional Static Stability 238

11.6.1 Fuselage 238

11.6.2 Wing 238

11.6.2.1 Dihedral 239

11.6.3 Sweepback 239

11.7 Propeller Slipstream 240

11.8 Neutral Directional Static Stability 240

11.9 Lateral Static Stability 240

11.10 Aeroplane Design Features Affecting Lateral Static Stability 242

11.10.1 Increased Lateral Static Stability 242

11.10.2 Decreased Lateral Static Stability 242

11.11 Sideslip Angle and Rolling Moment Coefficient 243

11.12 Analysis of Design Feature Effects 244

11.13 Wing Contribution 244

11.13.1 Dihedral 244

11.13.2 Anhedral 245

11.13.3 Sweepback 245

11.14 Wing/Fuselage Interference 246

11.14.1 Shielding Effect 246

11.14.2 Wing Location 246

11.15 Fuselage/Fin 246

11.15.1 Fin Size 246

11.15.2 Ventral Fin 246

11.16 Handling Considerations 247

11.16.1 Propeller Slipstream 247

11.16.2 Crosswind Landings 247

11.16.3 Flaps 247

11.17 Longitudinal Static Stability 248

11.18 The Centre of Pressure (CP) 249

11.19 The Neutral Point (NP) 250

11.19.1 Types of Static Neutral Point 250

11.19.1.1 The Stick-Free Static Neutral Point 250

11.19.1.2 The Stick-Fixed Static Neutral Point 250

11.19.2 The Effect of the CG at the NP 250

11.20 The Aerodynamic Centre (AC) 251

11.21 The Centre of Gravity (CG) 251

11.21.1 The CG Envelope 251

11.21.1.1 CG Envelope Limitations 251

11.21.1.2 CG Movement 252

11.21.2 The Effect of CG at the Limits 252

11.21.2.1 CG at the Forward Limit 252

11.21.2.2 CG at the Aft Limit 252

11.22 The Static Margin (SM) 253

11.23 The Trim Point (TP) 253

11.24 Longitudinal Dihedral 253

11.25 Aeroplane-Design Variations 255

11.26 The Effect of the Variables on Longitudinal Static Stability 255

11.26.1 Elevator Deflection 255

11.26.2 Trim 256

11.26.3 The Fuselage 257

11.26.4 Angle of Attack 257

11.26.5 Configuration 257

11.26.5.1 Trailing-Edge Flaps 257

11.26.5.2 Undercarriage 257

11.27 Stick-Fixed Longitudinal Static Stability 257

11.27.1 Stick-Position Stability 258

11.28 Stick-Free Longitudinal Static Stability 258

11.28.1 Stick Force 259

11.29 Certification Standard Stick-Force Requirements 260

11.29.1 a. Class ‘A’ Aeroplanes CS 25.173(c) 260

11.29.2 b. Class ‘B’ Aeroplanes CS 23.173(c) 260

11.30 The Effect of CG Position on Stick Force 260

11.31 Longitudinal Static Manoeuvre Stability 261

11.31.1 The Manoeuvre Point 261

11.32 Factors Affecting Stick Force 262

11.33 Summary 262

11.34 The Effect of Atmospheric Conditions 264

11.34.1 Ice Accretion 264

11.34.2 Heavy Rain 264

11.34.3 Altitude 264

11.35 The Factors Affecting Static Stability 264

Self-Assessment Exercise 11 267

12 Dynamic Stability 277

12.1 Longitudinal Dynamic Stability 279

12.1.1 The Phugoid 279

12.1.2 Short-Period Oscillation 280

12.1.3 Factors Affecting Longitudinal Dynamic Stability 280

12.2 Lateral Dynamic Stability 280

12.2.1 Sideslip 281

12.2.2 Rolling 281

12.2.3 Spiral 281

12.2.4 Dutch Roll 281

12.3 Spiral Instability 281

12.4 Dutch Roll 282

12.5 Asymmetric Thrust 282

12.6 Aerodynamic Damping 283

12.7 Summary 283

12.8 The Factors Affecting Dynamic Stability 283

12.8.1 a. General 283

12.8.2 b. Longitudinal 284

12.8.3 c. Lateral 284

Self-Assessment Exercise 12 285

Part 5 Manoeuvre Aerodynamics 289

13 Level-Flight Manoeuvres 291

13.1 The Manoeuvre Envelope 291

13.1.1 The Flight Load Factor 291

13.2 Manoeuvre-Envelope Limitations 291

13.2.1 The Stalling Speed 291

13.2.2 The ‘g’ Limitation 292

13.2.3 The Manoeuvre-Envelope Limiting Parameters 294

13.2.4 The Manoeuvre-Envelope Maximum-Speed Limitation 294

13.3 Stalling and Design Speed Definitions 294

13.4 Limiting Speeds 296

13.5 The Load Factor 296

13.6 The Gust Load Factor 297

13.7 Buffet 299

13.7.1 Low-Speed Buffet 299

13.7.2 High-Speed Buffet 300

13.8 The Buffet Onset Boundary Chart 300

13.9 Turns 302

13.9.1 The Load Factor in a Turn 303

13.9.2 The Turn Radius 303

13.9.3 Rate of Turn 305

13.10 Turn and Slip Indications 306

Self-Assessment Exercise 13 307

14 Climb and Descent Aerodynamics 315

14.1 Climbing Flight 315

14.2 The Forces in a Climb 315

14.3 The Effect of the Variables on the Climb 316

14.3.1 Altitude 316

14.3.2 Mass 316

14.3.3 Flap Setting 316

14.3.4 Wind Component 317

14.4 Climb Gradient 317

14.5 Climb-Gradient Calculations 318

14.5.1 Method 1 318

14.5.2 Method 2 320

14.6 Rate of Climb 321

14.7 Rate-of-Climb Calculations 321

14.8 VX and VY 323

14.9 VX 323

14.10 VY 325

14.11 Aircraft Ceiling 326

14.12 VY at the Absolute Ceiling 327

14.12.1 Piston/Propeller Aeroplanes 328

14.12.2 Jet Aeroplanes 328

14.13 The Effect of the Variables on VX and VY 329

14.13.1 Mass 329

14.13.2 Flap 329

14.13.3 Altitude 329

14.13.4 Temperature 329

14.13.5 Wind Component 329

14.14 The Effect of Climbing-Speed Variations 331

14.15 Factors Affecting the Climb 332

14.16 The Glide Descent 332

14.16.1 The Glide Variables 333

14.17 Gliding for Maximum Range 334

14.18 The Effect of the Variables on a Glide Descent 335

14.18.1 Speed 335

14.18.2 Wind Component 336

14.18.3 Mass 337

14.18.4 Angle of Attack 338

14.18.5 Flap 338

14.19 Gliding for Maximum Endurance 338

14.20 Climbing and Descending Turns 339

Self-Assessed Exercise 14 341

Part 6 Other Aerodynamic Considerations 349

15 High-Speed Flight 351

15.0.1 General Introduction 351

15.1 High-Speed Definitions 352

15.2 High-Speed Calculations 352

15.3 The Shockwave 353

15.3.1 Compressibility 353

15.3.2 Shockwave Formation 353

15.4 Air-Pressure-Wave Patterns 354

15.4.1 Subsonic 357

15.4.2 Sonic 357

15.4.3 Supersonic 357

15.5 The Shockwave Deflection Angle 357

15.6 The High-Speed CP 358

15.7 Critical Mach Number (MCRIT) 358

15.8 The Effect of a Shockwave 359

15.8.1 Wave Drag 359

15.8.2 Drag Divergence Mach Number 360

15.9 The Flying Controls 360

15.10 The Effect of the Aerofoil Profile 361

15.10.1 Thickness/Chord Ratio 362

15.10.2 Wing Camber 362

15.11 Swept Wings 362

15.12 The Effect of Sweepback 362

15.12.1 The Advantages of Sweepback 362

15.12.1.1 Increased MCRIT 363

15.12.1.2 Aerodynamic Effects 363

15.12.2 The Disadvantages of Sweepback 363

15.13 Remedial Design Features 364

15.13.1 Low-Speed Ailerons 365

15.13.2 High-Speed Ailerons 365

15.14 Area Rule 365

15.15 High-Speed-Flight Characteristics 367

15.15.1 High-Speed Buffet 367

15.15.2 Tuck Under 367

15.15.3 The Shock Stall 367

15.15.4 The Buffet Boundary 368

15.15.5 Coffin Corner 368

15.16 Speed Instability 368

15.16.1 The Mach Trimmer 369

15.16.2 Lateral Instability 369

15.17 The Supercritical Wing 369

15.18 Supersonic Airflow 370

15.18.1 The Convex Corner Mach Wave (Expansion Wave) 370

15.18.2 The Concave-Corner Shockwave 372

Self-Assessment Exercise 15 373

16 Propellers 387

16.1 Propeller Definitions 387

16.2 Basic Principles 389

16.3 Factors Affecting Propeller Efficiency 391

16.4 Airspeed 391

16.4.1 Fixed-Pitch Propellers 391

16.4.2 Variable-Pitch Propellers 393

16.5 Power Absorption 393

16.5.1 Propeller-Blade Shape 393

16.5.1.1 Blade Length 393

16.5.1.2 Blade Chord 394

16.5.2 Propeller-Blade Number 394

16.5.3 Solidity 394

16.6 The Effects of a Propeller on Aeroplane Performance 395

16.6.1 Torque 395

16.6.2 Slipstream Effect 396

16.6.3 Asymmetric Blade 396

16.6.4 Gyroscopic Effect 397

16.7 Propeller Forces and Moments 398

16.7.1 Centrifugal Force (CF) 398

16.7.2 Centrifugal Twisting Moment (CTM) 398

16.7.3 Aerodynamic Twisting Moment (ATM) 398

16.8 Propeller-Blade Positions 400

16.9 The Constant-Speed Unit (CSU) 400

16.9.1 Propeller Windmilling 401

16.9.2 Propeller Feathering 401

16.9.3 Reverse Pitch 403

16.10 The Effect of a Constant Speed Propeller on a Glide Descent 403

16.11 Engine Failure 403

Self-Assessment Exercise 16 405

17 Operational Considerations 411

17.1 Runway-Surface Contamination 411

17.1.1 Surface Contaminants 411

17.1.1.1 Standing Water 411

17.1.1.2 Slush 411

17.1.1.3 Wet Snow 411

17.1.1.4 Dry Snow 412

17.1.1.5 Very Dry Snow 412

17.1.1.6 Compacted Snow 412

17.1.1.7 Ice 412

17.1.1.8 Specially Prepared Winter Runway 412

17.1.1.9 Mixtures 412

17.1.1.10 Contaminant Drag 413

17.1.1.11 Water-Equivalent Depth 413

17.2 The Effect of Runway Contamination 413

17.2.1 Take-off 413

17.3 Aeroplane Contamination 415

17.3.1 The Effect of Heavy Rain 415

17.3.2 The Effect of Propeller Icing 415

17.3.3 The Effect of Airframe Icing 416

17.3.4 The Effect of Airframe-Surface Damage 416

17.3.5 The Effect of Turbulence 416

17.4 Windshear 417

17.4.1 The Effect of Windshear 417

17.4.1.1 Energy Loss 417

17.4.1.2 Energy Gain 417

17.4.2 Downdraught 418

17.4.2.1 Take-off 418

17.4.2.2 Landing 418

17.4.3 Countering Windshear 419

Self-Assessment Exercise 17 421

Part 7 Conclusion 425

18 Summary 427

18.1 Aerofoil-Profile Definitions 427

18.2 Aerofoil-Attitude Definitions 427

18.3 Wing-Shape Definitions 428

18.4 High-Speed Definitions 428

18.5 Propeller Definitions 429

18.6 V Speeds 430

18.7 Po F Formulae 432

18.7.1 Drag 433

18.7.2 Wing Loading/Load Factor 433

18.7.3 Stalling Speed Calculations 434

18.7.3.1 Mass Change 434

18.7.3.2 Load Factor 434

18.7.3.3 Turn 434

18.7.4 Design Manoeuvre Speed (VA) 434

18.7.5 Turn Details 434

18.7.5.1 Radius of Turn 434

18.7.5.2 Rate of Turn 434

18.7.6 Climb Calculations 434

18.7.7 Descent Calculations 434

18.7.7.1 Maximum Glide Range 435

18.7.8 Mach Angle (µ) Calculation 435

18.8 Key Facts 435

18.9 Stalling 435

18.9.1 The Maximum Coefficient of Lift (CLmax) 435

18.9.2 The Critical Angle 435

18.9.3 The Stalling Speed 436

18.10 Stability 436

18.10.1 Static Stability 436

18.10.2 Dynamic Stability 436

18.10.3 The Stick Force 438

18.10.4 The Gust Load Factor 439

18.11 Propellers 439

18.11.1 Propeller Efficiency 439

18.11.2 Fixed Pitch Angle of Attack 439

18.11.3 Propeller Gyroscopic Effect 440

18.12 The Effect of the Variables on Performance 440

18.12.1 Airframe Surface 440

18.12.2 Airframe Surface 440

18.12.3 Altitude 441

18.12.4 Aspect Ratio 441

18.12.5 Camber 441

18.12.6 CG Position 442

18.12.7 Flap 442

18.12.8 Sweepback 443

18.12.9 Dihedral 443

18.12.10 Mass 443

Self-Assessment Exercise 18 445

19 Solutions (with page references) 447

Self-Assessment Exercise 1 447

Self-Assessment Exercise 2 447

Self-Assessment Exercise 3 448

Self-Assessment Exercise 4 448

Self-Assessment Exercise 5 448

Self-Assessment Exercise 6 449

Self-Assessment Exercise 7 450

Self-Assessment Exercise 8 451

Self-Assessment Exercise 9 452

Self-Assessment Exercise 10 453

Self-Assessment Exercise 11 453

Self-Assessment Exercise 12 454

Self-Assessment Exercise 13 454

Self-Assessment Exercise 14 456

14.0.1 Vx &Vy Mathematical Proof 457

Self-Assessment Exercise 15 458

Self-Assessment Exercise 16 459

Self-Assessment Exercise 17 459

Self-Assessment Exercise 18 Turn Calculations 460

Index 461