Table Of Content

AIRCRAFT DESIGN Aerospace Series List Introduction to UAV Systems 4e Fahlstrom and Gleason August 2012 Theory of Lift: Introductory Computational Aerodynamics with MATLAB/ Octave McBain August 2012 Sense and Avoid in UAS: Research and Applications Angelov April 2012 Morphing Aerospace Vehicles and Structures Valasek April 2012 Gas Turbine Propulsion Systems MacIsaac and Langton July 2011 Basic Helicopter Aerodynamics, 3rd Edition Seddon and Newman July 2011 Advanced Control of Aircraft, Spacecraft and Rockets Tewari July 2011 Cooperative Path Planning of Unmanned Aerial Vehicles Tsourdos et al November 2010 Principles of Flight for Pilots Swatton October 2010 Air Travel and Health: A Systems Perspective Seabridge et al September 2010 Design and Analysis of Composite Structures: With applications to aerospace Structures Kassapoglou September 2010 Unmanned Aircraft Systems: UAVS Design, Development and Deployment Austin April 2010 Introduction to Antenna Placement & Installations Macnamara April 2010 Principles of Flight Simulation Allerton October 2009 Aircraft Fuel Systems Langton et al May 2009 The Global Airline Industry Belobaba April 2009 Computational Modelling and Simulation of Aircraft and the Environment: Volume 1 – Platform Kinematics and Synthetic Environment Diston April 2009 Handbook of Space Technology Ley, Wittmann Hallmann April 2009 Aircraft Performance Theory and Practice for Pilots Swatton August 2008 Surrogate Modelling in Engineering Design: A Practical Guide Forrester, Sobester, Keane August 2008 Aircraft Systems, 3rd Edition Moir & Seabridge March 2008 Introduction to Aircraft Aeroelasticity And Loads Wright & Cooper December 2007 Stability and Control of Aircraft Systems Langton September 2006 Military Avionics Systems Moir & Seabridge February 2006 Design and Development of Aircraft Systems Moir & Seabridge June 2004 Aircraft Loading and Structural Layout Howe May 2004 Aircraft Display Systems Jukes December 2003 Civil Avionics Systems Moir & Seabridge December 2002 AIRCRAFT DESIGN A Systems Engineering Approach Mohammad H. Sadraey Daniel Webster College, New Hampshire, USA A John Wiley & Sons, Ltd., Publication This edition first published 2013  2013, John Wiley & Sons, Ltd Registered office John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, United Kingdom For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com. The right of the author to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. MATLAB is a trademark of The MathWorks, Inc. and is used with permission. The MathWorks does not warrant the accuracy of the text or exercises in this book. This book’s use or discussion of MATLAB software or related products does not constitute endorsement or sponsorship by The MathWorks of a particular pedagogical approach or particular use of the MATLAB software. Library of Congress Cataloging-in-Publication Data Sadraey, Mohammad H. Aircraft design : a systems engineering approach / Mohammad H. Sadraey. pages cm Includes bibliographical references and index. ISBN 978-1-119-95340-1 (hardback) 1. Airplanes–Design and construction. I. Title. TL671.2.S3136 2012 629.134′1–dc23 2012009907 A catalogue record for this book is available from the British Library. Print ISBN: 9781119953401 Set in 10/12pt Times by Laserwords Private Limited, Chennai, India. To Fatemeh Zafarani, Ahmad, and Atieh For all their love and understanding Contents Preface xv Series Preface xix Acknowledgments xxi Symbols and Acronyms xxiii 1 Aircraft Design Fundamentals 1 1.1 Introduction to Design 1 1.2 Engineering Design 4 1.3 Design Project Planning 8 1.4 Decision Making 10 1.5 Feasibility Analysis 12 1.6 Tort of Negligence 15 References 17 2 Systems Engineering Approach 19 2.1 Introduction 19 2.2 Fundamentals of Systems Engineering 20 2.3 Conceptual System Design 23 2.3.1 Definition 23 2.3.2 Conceptual Design Flowchart 24 2.3.3 Technical Performance Measures 25 2.3.4 Functional Analysis 26 2.3.5 System Trade-Off Analysis 27 2.3.6 Conceptual Design Review 28 2.4 Preliminary System Design 29 2.5 Detail System Design 30 2.6 Design Requirements 33 2.7 Design Review, Evaluation, and Feedback 34 2.8 Systems Engineering Approach in Aircraft Design 37 2.8.1 Implementation of Systems Engineering 37 viii Contents 2.8.2 Design Phases 38 2.8.3 Design Flowchart 39 2.8.4 Design Groups 41 2.8.5 Design Steps 43 References 47 3 Aircraft Conceptual Design 49 3.1 Introduction 49 3.2 Primary Functions of Aircraft Components 50 3.3 Aircraft Configuration Alternatives 52 3.3.1 Wing Configuration 53 3.3.2 Tail Configuration 55 3.3.3 Propulsion System Configuration 55 3.3.4 Landing Gear Configuration 56 3.3.5 Fuselage Configuration 58 3.3.6 Manufacturing-Related Items Configuration 58 3.3.7 Subsystems Configuration 59 3.4 Aircraft Classification and Design Constraints 62 3.5 Configuration Selection Process and Trade-Off Analysis 68 3.6 Conceptual Design Optimization 74 3.6.1 Mathematical Tools 74 3.6.2 Methodology 76 Problems 86 References 92 4 Preliminary Design 93 4.1 Introduction 93 4.2 Maximum Take-Off Weight Estimation 94 4.2.1 The General Technique 94 4.2.2 Weight Build-up 95 4.2.3 Payload Weight 96 4.2.4 Crew Weight 97 4.2.5 Fuel Weight 100 4.2.6 Empty Weight 108 4.2.7 Practical Steps of the Technique 112 4.3 Wing Area and Engine Sizing 113 4.3.1 Summary of the Technique 113 4.3.2 Stall Speed 118 4.3.3 Maximum Speed 120 4.3.4 Take-Off Run 131 4.3.5 Rate of Climb 136 4.3.6 Ceiling 140 4.4 Design Examples 145 Problems 155 References 158 Contents ix 5 Wing Design 161 5.1 Introduction 161 5.2 Number of Wings 164 5.3 Wing Vertical Location 165 5.3.1 High Wing 165 5.3.2 Low Wing 168 5.3.3 Mid-Wing 169 5.3.4 Parasol Wing 169 5.3.5 The Selection Process 169 5.4 Airfoil Section 170 5.4.1 Airfoil Design or Airfoil Selection 171 5.4.2 General Features of an Airfoil 173 5.4.3 Characteristic Graphs of an Airfoil 176 5.4.4 Airfoil Selection Criteria 182 5.4.5 NACA Airfoils 183 5.4.6 Practical Steps for Wing Airfoil Section Selection 188 5.5 Wing Incidence 195 5.6 Aspect Ratio 198 5.7 Taper Ratio 203 5.8 The Significance of Lift and Load Distributions 206 5.9 Sweep Angle 209 5.10 Twist Angle 223 5.11 Dihedral Angle 226 5.12 High-Lift Device 230 5.12.1 The Functions of a High-Lift Device 230 5.12.2 High-Lift Device Classification 232 5.12.3 Design Technique 235 5.13 Aileron 241 5.14 Lifting-Line Theory 242 5.15 Accessories 246 5.15.1 Strake 247 5.15.2 Fence 247 5.15.3 Vortex Generator 248 5.15.4 Winglet 248 5.16 Wing Design Steps 249 5.17 Wing Design Example 250 Problems 259 References 264 6 Tail Design 265 6.1 Introduction 265 6.2 Aircraft Trim Requirements 268 6.2.1 Longitudinal Trim 270 6.2.2 Directional and Lateral Trim 276 6.3 A Review on Stability and Control 278 x Contents 6.3.1 Stability 278 6.3.2 Control 282 6.3.3 Handling Qualities 284 6.4 Tail Configuration 285 6.4.1 Basic Tail Configuration 285 6.4.2 Aft Tail Configuration 288 6.5 Canard or Aft Tail 294 6.6 Optimum Tail Arm 298 6.7 Horizontal Tail Parameters 301 6.7.1 Horizontal Tail Design Fundamental Governing Equation 301 6.7.2 Fixed, All-Moving, or Adjustable 304 6.7.3 Airfoil Section 306 6.7.4 Tail Incidence 308 6.7.5 Aspect Ratio 311 6.7.6 Taper Ratio 312 6.7.7 Sweep Angle 313 6.7.8 Dihedral Angle 313 6.7.9 Tail Vertical Location 314 6.7.10 Other Tail Geometries 315 6.7.11 Control Provision 316 6.7.12 Final Check 316 6.8 Vertical Tail Design 317 6.8.1 Vertical Tail Design Requirements 317 6.8.2 Vertical Tail Parameters 319 6.9 Practical Design Steps 329 6.10 Tail Design Example 331 Problems 336 References 340 7 Fuselage Design 341 7.1 Introduction 341 7.2 Functional Analysis and Design Flowchart 341 7.3 Fuselage Configuration Design and Internal Arrangement 345 7.4 Ergonomics 346 7.4.1 Definitions 346 7.4.2 Human Dimensions and Limits 348 7.5 Cockpit Design 350 7.5.1 Number of Pilots and Crew Members 351 7.5.2 Pilot/Crew Mission 353 7.5.3 Pilot/Crew Comfort/Hardship Level 353 7.5.4 Pilot Personal Equipment 354 7.5.5 Control Equipment 355 7.5.6 Measurement Equipment 356 7.5.7 Level of Automation 357 7.5.8 External Constraints 359 Contents xi 7.5.9 Cockpit Integration 359 7.6 Passenger Cabin Design 360 7.7 Cargo Section Design 368 7.8 Optimum Length-to-Diameter Ratio 372 7.8.1 Optimum Slenderness Ratio for Lowest fLD 372 7.8.2 Optimum Slenderness Ratio for Lowest Fuselage Wetted Area 378 7.8.3 Optimum Slenderness Ratio for the Lightest Fuselage 380 7.9 Other Fuselage Internal Segments 380 7.9.1 Fuel Tanks 381 7.9.2 Radar Dish 385 7.9.3 Wing Box 386 7.9.4 Power Transmission Systems 387 7.10 Lofting 388 7.10.1 Aerodynamics Considerations 388 7.10.2 Area Ruling 390 7.10.3 Radar Detectability 392 7.10.4 Fuselage Rear Section 392 7.11 Fuselage Design Steps 394 7.12 Design Example 395 Problems 406 References 410 8 Propulsion System Design 413 8.1 Introduction 413 8.2 Functional Analysis and Design Requirements 414 8.3 Engine Type Selection 416 8.3.1 Aircraft Engine Classification 417 8.3.2 Selection of Engine Type 428 8.4 Number of Engines 436 8.4.1 Flight Safety 437 8.4.2 Other Influential Parameters 438 8.5 Engine Location 439 8.5.1 Design Requirements 439 8.5.2 General Guidelines 441 8.5.3 Podded versus Buried 443 8.5.4 Pusher versus Tractor 444 8.5.5 Twin-Jet Engine: Under-Wing versus Rear Fuselage 446 8.6 Engine Installation 448 8.6.1 Prop-Driven Engine 450 8.6.2 Jet Engine 452 8.7 Propeller Sizing 456 8.8 Engine Performance 461 8.8.1 Prop-Driven Engine 461 8.8.2 Jet Engine 462 8.9 Engine Selection 462 xii Contents 8.10 Propulsion System Design Steps 464 8.11 Design Example 467 Problems 471 References 478 9 Landing Gear Design 479 9.1 Introduction 479 9.2 Functional Analysis and Design Requirements 481 9.3 Landing Gear Configuration 484 9.3.1 Single Main 484 9.3.2 Bicycle 485 9.3.3 Tail-Gear 487 9.3.4 Tricycle 487 9.3.5 Quadricycle 488 9.3.6 Multi-Bogey 489 9.3.7 Releasable Rail 489 9.3.8 Skid 489 9.3.9 Seaplane Landing Device 490 9.3.10 Human Leg 491 9.3.11 Landing Gear Configuration Selection Process 492 9.3.12 Landing Gear Attachment 493 9.4 Fixed, Retractable, or Separable Landing Gear 494 9.5 Landing Gear Geometry 497 9.5.1 Landing Gear Height 498 9.5.2 Wheel Base 503 9.5.3 Wheel Track 508 9.6 Landing Gear and Aircraft Center of Gravity 516 9.6.1 Tipback and Tipforward Angle Requirements 516 9.6.2 Take-Off Rotation Requirement 518 9.7 Landing Gear Mechanical Subsystems/Parameters 524 9.7.1 Tire Sizing 524 9.7.2 Shock Absorber 525 9.7.3 Strut Sizing 526 9.7.4 Steering Subsystem 527 9.7.5 Landing Gear Retraction System 527 9.8 Landing Gear Design Steps 528 9.9 Landing Gear Design Example 529 Problems 539 References 544 10 Weight of Components 547 10.1 Introduction 547 10.2 Sensitivity of Weight Calculation 549 10.3 Aircraft Major Components 553 10.4 Weight Calculation Technique 556 10.4.1 Wing Weight 559 Contents xiii 10.4.2 Horizontal Tail Weight 561 10.4.3 Vertical Tail Weight 561 10.4.4 Fuselage Weight 562 10.4.5 Landing Gear Weight 563 10.4.6 Installed Engine Weight 564 10.4.7 Fuel System Weight 564 10.4.8 Weight of Other Equipment and Subsystems 565 10.5 Chapter Examples 565 Problems 570 References 573 11 Aircraft Weight Distribution 575 11.1 Introduction 575 11.2 Aircraft Center of Gravity Calculation 578 11.3 Center of Gravity Range 585 11.3.1 Fixed or Variable Center of Gravity 585 11.3.2 Center of Gravity Range Definition 586 11.3.3 Ideal Center of Gravity Location 587 11.4 Longitudinal Center of Gravity Location 590 11.5 Technique to Determine the Aircraft Forward and Aft Center of Gravity 598 11.6 Weight Distribution Technique 606 11.6.1 Fundamentals of Weight Distribution 607 11.6.2 Longitudinal Stability Requirements 609 11.6.3 Longitudinal Controllability Requirements 611 11.6.4 Longitudinal Handling Quality Requirements 613 11.7 Aircraft Mass Moment of Inertia 615 11.8 Chapter Example 620 Problems 624 References 630 12 Design of Control Surfaces 631 12.1 Introduction 631 12.2 Configuration Selection of Control Surfaces 637 12.3 Handling Qualities 638 12.3.1 Definitions 640 12.3.2 Longitudinal Handling Qualities 643 12.3.3 Lateral-Directional Handling Qualities 647 12.4 Aileron Design 654 12.4.1 Introduction 654 12.4.2 Principles of Aileron Design 656 12.4.3 Aileron Design Constraints 664 12.4.4 Steps in Aileron Design 669 12.5 Elevator Design 670 12.5.1 Introduction 670 12.5.2 Principles of Elevator Design 672 12.5.3 Take-Off Rotation Requirement 676 xiv Contents 12.5.4 Longitudinal Trim Requirement 680 12.5.5 Elevator Design Procedure 683 12.6 Rudder Design 685 12.6.1 Introduction to Rudder Design 685 12.6.2 Fundamentals of Rudder Design 688 12.6.3 Rudder Design Steps 709 12.7 Aerodynamic Balance and Mass Balance 713 12.7.1 Aerodynamic Balance 715 12.7.2 Mass Balance 722 12.8 Chapter Examples 723 12.8.1 Aileron Design Example 723 12.8.2 Elevator Design Example 729 12.8.3 Rudder Design Example 738 Problems 745 References 752 Appendices 755 Appendix A: Standard Atmosphere, SI Units 755 Appendix B: Standard Atmosphere, British Units 756 Index 757 Preface Objectives The objective of this book is to provide a basic text for courses in the design of heavier- than-air vehicles at both the upper division undergraduate and beginning graduate levels. Aircraft design is a special topic in the aeronautical/aerospace engineering discipline. The academic major of aeronautical/aerospace engineering traditionally tends to have four main areas of expertise: aerodynamics, flight dynamics, propulsion, and structure. A qualified aircraft designer employs all these four scientific concepts and principles and integrates them using special design techniques to design a coordinated unique system; an aircraft. Design is a combination of science, art, and techniques. A designer not only must have sufficient level of knowledge in these four areas, but also needs to employ mathematics, skills, experiences, creativity, art, and system design techniques. It is true that aircraft design is not completely teachable in classrooms, but combining class lectures with a semester-long aircraft design project provides the best opportunity for students to learn and experience aircraft design. Every aeronautical engineering discipline offers at least one course in aircraft design or aerospace system design. The lack of an aircraft design textbook with academic features – such as full coverage of all aspects of an air vehicle, aeronautical concepts, design methods, design flowcharts, design examples, and end-of-chapter problems – combined with the newly developed systems engineering techniques was the main motivation to write this book. In the past several years, I have talked to various aircraft design instructors and students at conferences and AIAA Design/Build/Fly design competitions. I came to the conclusion that the great design books published by such pioneers as Roskam, Toren- beek, Nicolai, Stinton, and Raymer need more development and expansion. This is to meet the ever-increasing need of universities and colleges for aircraft design education, and of industries for design implementation. The new text should possess significant features such as systems engineering approaches, design procedures, solved examples, and end-of-chapter problems. This book was written with the aim of filling the gap for aeronautical/aerospace engineering students and also for practicing engineers.