ADVANCED AIRCRAFT DESIGN -- Contents -- Foreword -- Series Preface -- Preface -- Acknowledgements -- 1 Design of theWell-Tempered Aircraft -- 1.1 How Aircraft Design Developed -- 1.1.1 Evolution of Jetliners and Executive Aircraft -- 1.1.2 A Framework for Advanced Design -- 1.1.3 Analytical Design Optimization -- 1.1.4 Computational Design Environment -- 1.2 Concept Finding -- 1.2.1 Advanced Design -- 1.2.2 Pre-conceptual Studies -- 1.3 Product Development -- 1.3.1 Concept Definition -- 1.3.2 Preliminary Design -- 1.3.3 Detail Design -- 1.4 Baseline Design in a Nutshell -- 1.4.1 Baseline Sizing -- 1.4.2 Power Plant -- 1.4.3 Weight and Balance -- 1.4.4 Structure -- 1.4.5 Performance Analysis -- 1.4.6 Closing the Loop -- 1.5 Automated Design Synthesis -- 1.5.1 Computational Systems Requirements -- 1.5.2 Examples -- 1.5.3 Parametric Surveys -- 1.6 Technology Assessment -- 1.7 Structure of the Optimization Problem -- 1.7.1 Analysis Versus Synthesis -- 1.7.2 Problem Classification -- Bibliography -- 2 Early Conceptual Design -- 2.1 Scenario and Requirements -- 2.1.1 What Drives a Design? -- 2.1.2 Civil Airplane Categories -- 2.1.3 Top Level Requirements -- 2.2 Weight Terminology and Prediction -- 2.2.1 Method Classification -- 2.2.2 Basic Weight Components -- 2.2.3 Weight Limits -- 2.2.4 Transport Capability -- 2.3 The Unity Equation -- 2.3.1 Mission Fuel -- 2.3.2 Empty Weight -- 2.3.3 Design Weights -- 2.4 Range Parameter -- 2.4.1 Aerodynamic Efficiency -- 2.4.2 Specific Fuel Consumption and Overall Efficiency -- 2.4.3 Best Cruise Speed -- 2.5 Environmental Issues -- 2.5.1 Energy and Payload Fuel Efficiency -- 2.5.2 'Greener by Design' -- Bibliography -- 3 Propulsion and Engine Technology -- 3.1 Propulsion Leading the Way -- 3.2 Basic Concepts of Jet Propulsion -- 3.2.1 Turbojet Thrust -- 3.2.2 Turbofan Thrust -- 3.2.3 Specific Fuel Consumption.

3.2.4 Overall Efficiency -- 3.2.5 Thermal and Propulsive Efficiency -- 3.2.6 Generalized Performance -- 3.2.7 Mach Number and Altitude Effects -- 3.3 Turboprop Engines -- 3.3.1 Power and Specific Fuel Consumption -- 3.3.2 Generalized Performance -- 3.3.3 High Speed Propellers -- 3.4 Turbofan Engine Layout -- 3.4.1 Bypass Ratio Trends -- 3.4.2 Rise and Fall of the Propfan -- 3.4.3 Rebirth of the Open Rotor? -- 3.5 Power Plant Selection -- 3.5.1 Power Plant Location -- 3.5.2 Alternative Fuels -- 3.5.3 Aircraft Noise -- Bibliography -- 4 Aerodynamic Drag and Its Reduction -- 4.1 Basic Concepts -- 4.1.1 Lift, Drag and Aerodynamic Efficiency -- 4.1.2 Drag Breakdown and Definitions -- 4.2 Decomposition Schemes and Terminology -- 4.2.1 Pressure and Friction Drag -- 4.2.2 Viscous Drag -- 4.2.3 Vortex Drag -- 4.2.4 Wave Drag -- 4.3 Subsonic Parasite and Induced Drag -- 4.3.1 Parasite Drag -- 4.3.2 Monoplane Induced Drag -- 4.3.3 Biplane Induced Drag -- 4.3.4 Multiplane and Boxplane Induced Drag -- 4.4 Drag Polar Representations -- 4.4.1 Two-term Approximation -- 4.4.2 Three-term Approximation -- 4.4.3 Reynolds Number Effects -- 4.4.4 Compressibility Correction -- 4.5 Drag Prediction -- 4.5.1 Interference Drag -- 4.5.2 Roughness and Excrescences -- 4.5.3 Corrections Dependent on Operation -- 4.5.4 Estimation of Maximum Subsonic L/D -- 4.5.5 Low-Speed Configuration -- 4.6 Viscous Drag Reduction -- 4.6.1 Wetted Area -- 4.6.2 Turbulent Friction Drag -- 4.6.3 Natural Laminar Flow -- 4.6.4 Laminar Flow Control -- 4.6.5 Hybrid Laminar Flow Control -- 4.6.6 Gains, Challenges and Barriers of LFC -- 4.7 Induced Drag Reduction -- 4.7.1 Wing Span -- 4.7.2 Spanwise Camber -- 4.7.3 Non-planar Wing Systems -- Bibliography -- 5 From Tube and Wing to Flying Wing -- 5.1 The Case for Flying Wings -- 5.1.1 Northrop's All-Wing Aircraft -- 5.1.2 Flying Wing Controversy.

5.1.3 Whither All-Wing Airliners? -- 5.1.4 Fundamental Issues -- 5.2 Allocation of Useful Volume -- 5.2.1 Integration of the Useful Load -- 5.2.2 Study Ground Rules -- 5.2.3 Volume Ratio -- 5.2.4 Zero-Lift Drag -- 5.2.5 Generalized Aerodynamic Efficiency -- 5.2.6 Partial Optima -- 5.3 Survey of Aerodynamic Efficiency -- 5.3.1 Altitude Variation -- 5.3.2 Aspect Ratio and Span -- 5.3.3 Engine-Airframe Matching -- 5.4 Survey of the Parameter ML/D -- 5.4.1 Optimum Flight Conditions -- 5.4.2 The Drag Parameter -- 5.5 Integrated Configurations Compared -- 5.5.1 Conventional Baseline -- 5.5.2 Is a Wing Alone Sufficient? -- 5.5.3 Blended Wing Body -- 5.5.4 Hybrid Flying Wing -- 5.5.5 Span Loader -- 5.6 Flying Wing Design -- 5.6.1 Hang-Ups or Showstopper? -- 5.6.2 Structural Design and Weight -- 5.6.3 The Flying Wing: Will It Fly? -- Bibliography -- 6 Clean Sheet Design -- 6.1 Dominant and Radical Configurations -- 6.1.1 Established Configurations -- 6.1.2 New Paradigms -- 6.2 Morphology of Shapes -- 6.2.1 Classification -- 6.2.2 Lifting Systems -- 6.2.3 Plan View Classification -- 6.2.4 Strut-Braced Wings -- 6.2.5 Propulsion and Concept Integration -- 6.3 Wing and Tail Configurations -- 6.3.1 Aerodynamic Limits -- 6.3.2 The Balanced Design -- 6.3.3 Evaluation -- 6.3.4 Relaxed Inherent Stability -- 6.4 Aircraft Featuring a Foreplane -- 6.4.1 Canard Configuration -- 6.4.2 Three-Surface Aircraft -- 6.5 Non-Planar Lifting Systems -- 6.5.1 Transonic Boxplane -- 6.5.2 C-Wing -- 6.6 Joined Wing Aircraft -- 6.6.1 Structural Principles and Weight -- 6.6.2 Aerodynamic Aspects -- 6.6.3 Stability and Control -- 6.6.4 Design Integration -- 6.7 Twin-Fuselage Aircraft -- 6.7.1 Design Integration -- 6.8 Hydrogen-Fuelled Commercial Transports -- 6.8.1 Properties of LH2 -- 6.8.2 Fuel System -- 6.8.3 Handling Safety, Economics and Logistics -- 6.9 Promising Concepts.

Bibliography -- 7 Aircraft Design Optimization -- 7.1 The Perfect Design: An Illusion? -- 7.2 Elements of Optimization -- 7.2.1 Design Parameters -- 7.2.2 Optimal Control and Discrete-Variable Optimization -- 7.2.3 Basic Terminology -- 7.2.4 Single-Objective Optimization -- 7.2.5 Unconstrained Optimizer -- 7.2.6 Constrained Optimizer -- 7.3 Analytical or Numerical Optimization? -- 7.3.1 Analytical Approach -- 7.3.2 Multivariate Optimization -- 7.3.3 Unconstrained Optimization -- 7.3.4 Constrained Optimization -- 7.3.5 Response Surface Approximation -- 7.3.6 Global Models -- 7.4 Large Optimization Problems -- 7.4.1 Concept Sizing and Evaluation -- 7.4.2 Multidisciplinary Optimization -- 7.4.3 System Decomposition -- 7.4.4 Multilevel Optimization -- 7.4.5 Multi-Objective Optimization -- 7.5 Practical Optimization in Conceptual Design -- 7.5.1 Arguments of the Sceptic -- 7.5.2 Problem Structure -- 7.5.3 Selecting Selection Variables -- 7.5.4 Design Sensitivity -- 7.5.5 The Objective Function -- Bibliography -- 8 Theory of OptimumWeight -- 8.1 Weight Engineering: Core of Aircraft Design -- 8.1.1 Prediction Methods -- 8.1.2 Use of Statistics -- 8.2 Design Sensitivity -- 8.2.1 Problem Structure -- 8.2.2 Selection Variables -- 8.3 Jet Transport Empty Weight -- 8.3.1 Weight Breakdown -- 8.3.2 Wing Structure (Item 10) -- 8.3.3 Fuselage Structure (Item 11) -- 8.3.4 Empennage Structure (Items 12 and 13) -- 8.3.5 Landing Gear Structure (Item 14) -- 8.3.6 Power Plant and Engine Pylons (Items 2 and 15) -- 8.3.7 Systems, Furnishings and Operational Items (Items 3, 4 and 5) -- 8.3.8 Operating Empty Weight: Example -- 8.4 Design Sensitivity of Airframe Drag -- 8.4.1 Drag Decomposition -- 8.4.2 Aerodynamic Efficiency -- 8.5 Thrust, Power Plant and Fuel Weight -- 8.5.1 Installed Thrust and Power Plant Weight -- 8.5.2 Mission Fuel -- 8.5.3 Propulsion Weight Penalty.

8.5.4 Wing and Propulsion Weight Fraction -- 8.5.5 Optimum Weight Fractions Compared -- 8.6 Take-Off Weight, Thrust and Fuel Efficiency -- 8.6.1 Maximum Take-Off Weight -- 8.6.2 Installed Thrust and Fuel Energy Efficiency -- 8.6.3 Unconstrained Optima Compared -- 8.6.4 Range for Given MTOW -- 8.6.5 Extended Range Version -- 8.7 Summary and Reflection -- 8.7.1 Which Figure of Merit? -- 8.7.2 Conclusion -- 8.7.3 Accuracy -- Bibliography -- 9 Matching Engines and Airframe -- 9.1 Requirements and Constraints -- 9.2 Cruise-Sized Engines -- 9.2.1 Installed Take-Off Thrust -- 9.2.2 The Thumbprint -- 9.3 Low Speed Requirements -- 9.3.1 Stalling Speed -- 9.3.2 Take-Off Climb -- 9.3.3 Approach and Landing Climb -- 9.3.4 Second Segment Climb Gradient -- 9.4 Schematic Take-Off Analysis -- 9.4.1 Definitions of Take-Off Field Length -- 9.4.2 Take-Off Run -- 9.4.3 Airborne Distance -- 9.4.4 Take-Off Distance -- 9.4.5 Generalized Thrust and Span Loading Constraint -- 9.4.6 Minimum Thrust for Given TOFL -- 9.5 Approach and Landing -- 9.5.1 Landing Distance Analysis -- 9.5.2 Approach Speed and Wing Loading -- 9.6 Engine Selection and Installation -- 9.6.1 Identifying the Best Match -- 9.6.2 Initial Engine Assessment -- 9.6.3 Engine Selection -- Bibliography -- 10 Elements of Aerodynamic Wing Design -- 10.1 Introduction -- 10.1.1 Problem Structure -- 10.1.2 Relation to Engine Selection -- 10.2 Planform Geometry -- 10.2.1 Wing Area and Design Lift Coefficient -- 10.2.2 Span and Aspect Ratio -- 10.3 Design Sensitivity Information -- 10.3.1 Aerodynamic Efficiency -- 10.3.2 Propulsion Weight Contribution -- 10.3.3 Wing and Tail Structure Weight -- 10.3.4 Wing Penalty Function and MTOW -- 10.4 Subsonic Aircraft Wing -- 10.4.1 Problem Structure -- 10.4.2 Unconstrained Optima -- 10.4.3 Minimum Propulsion Weight Penalty -- 10.4.4 Accuracy -- 10.5 Constrained Optima.

10.5.1 Take-Off Field Length.