Synthesis of Subsonic Aitplane Design978-94-017-3202-4/1.pdfSubsonic Airplane Design An introduction...
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Synthesis of Subsonic Aitplane Design
Transcript of Synthesis of Subsonic Aitplane Design978-94-017-3202-4/1.pdfSubsonic Airplane Design An introduction...
Synthesis of Subsonic Aitplane Design
Synthesis of Subsonic Airplane Design
An introduction to the preliminary design of subsonic general aviation and transport aircraft, with emphasis on layout, aerodynamic design, propulsion and performance
Egbert Torenbeek
with a foreword by H. Wittenberg
1982
fi SPRINGER-SCIENCE+BUSINESS MEDIA, B.V.
Library of Congress Cataloging in Publication Data
Torenbeek, Egbert. Synthesis of Subsonic Aiiplane Design.
Includes bibliographical references and index. 1. Airplanes-Design and Construction. I. Title. TL671.2.T67 1982 629.134'1 82-12469
ISBN 978-90-481-8273-2 ISBN 978-94-017-3202-4 (eBook) DOI 10.1007/978-94-017-3202-4
Reprinted 1984,1985,1987,1988,1990,1993, 1995, 1996.
Copyright© 1982 by Springer Science+Business Media Dordrecht Originally published by Kluwer Academic Publishers in 1982
CIP
All rights reserved. No palt of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, mechanical, photocopying, recording, or otherwise, without written permission of the copyright owner, Springer-Science+Business Media, B.V.
Contents
FOREWORD
by Professor H. Wittenberg
AUTHOR'S PREFACE
ACKNOWLEDGE11ENTS
UNITS
CHAPTER 1. GENERAL ASPECTS OF AIRCRAFT CONFIGURATION DEVELOPMENT
1.1. Introduction
1.2. Aircraft design and development 1.3. Configuration development
1.3.1. The design concept 1.3.2. Initial configuration design and configuration variations 1.3.3. Baseline configuration development 1.3.4. The preliminary design department
1.4. The initial specification 1.4.1. The need for a new type of aircraft 1.4.2. Transport capacity 1.4.3. Design cruising speed and range 1.4.4. Low-speed characteristics and field performance 1.4.5. Other requirements
1.5. A continuous thread running through the design process 1.5.1. The iterative character of design 1.5.2. Searching for the optimum 1.5.3. A suggested scheme for preliminary design
1.6. Impact of civil airworthiness requirements, and operating and flight rules 1.6.1. General
1.6.2. Federal Aviation Regulations 1.6.3. British Civil Airworthiness Requirements 1.6.4. Airworthiness standards and desig~
1.7. Conclusion
CHAPTER 2. THE GENERAL ARRANGEMENT
2.1. Introduction
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2. 2. Hj_gh , low or mid wing?
2. 2. 1. High wing
2.2.2. Mid win9 2.2.3. Low wing
2.2.4. Effects of wing location on the general arrangement 2.3. Location of the engines
2.3.1. Propeller aircraft
2.3.2. Jet-propelled transport aircraft
2.3.3. Single-engine subsonic jet aircraft
2.4. Arrangement of the tailplane
2.4.1. Classification of tail surface configurations
2.4.2. The location of tail surfaces 2.5. Arrangement of the undercarriage
2.5.1. Tailwheel undercarriage 2.5.2. Nosewheel undercarriage
2.5.3. Tandem undercarriage
2 •. 6. Some unconventional aircraft configurations
2.6.1. The flying wing
2.6.2. Tailless aircraft
2.6.3. Tail-first (or canard) layout
CHAPTER 3. FUSELAGE DESIGN
3.1. Introduction 3.1.1. Function and design requirements
3.1.2. Drag and optimization of the external shape
3. 1. 3. A design procedure for fuselages with cylindrical mid-se.ction
3.2. The fuselage of airliners and general aviation aircraft
3.2.1. Importance of comfort and payload density
3.2.2. Cabin design
3.2.3. Passenger seats
3.2.4. Passenger emergency exits, doors and windows
3.2.5. Cargo holds
3.2.6. Services
3.3. The fuselage of cargo aircraft
3.3.1. The case for the civil freighter
3. 3. 2. Payload density and volume of. the freight hold
3.3.3. Loading systems
3.3.4. Accessibility of the freight hold
3.4. Flight deck design
3.4.1. Location of the pilot's seat and the flight controls
3.4.2. Visibility from the cockpit
3.4.3. Flight deck dimensions and layout
3.4.4. Emergency exits for crew members 3.5. Some remarks concerning the external shape
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3.5.1. Fuselages with a cylindrical mid-section
3.5.2. Fuselages for relatively small useful loads
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CHAPTER 4. AN APPRECIATION OF SUBSONIC ENGINE TECHNOLOGY
4.1. Introductory comparison of engine types
4.2. Current reciprocating engines
4.2.1. Some characteristics of the four stroke engine
4.2.2. Engine design and its influence on flight performance
4.2.3. Engine classification by cylinder arrangement
4.2.4. Two-stroke and Rotary Combustion engines
4.3. Basic properties of aircraft gas turbines for subsonic speeds
4.3.1. The gas producer
4.3.2. The propulsive device
4.3.3. The pure jet engine
4.3.4. The turbofan engine
4.3.5. The turboprop engine
4.3.6. Overall efficiency, specific fuel consumption and specific thrust
(power)
4.3.7. Analysis of the engine cycle
4.4. Assessment of turbojet engines
4.4 .1. Overall Pressure Ratio
4. 4. 2. Turbine Entry Temperature
4. 4. 3. Bypass ratio
4. 4. 4. Engine noise
4.4.5. Summary and prognosis for the turbofan engine
4.4.6.tEngine performance in non-standard atmosphere 4.5. Assessment of turboprop engines
4.5.1. Performance
4.5.2. Weight and drag
4.5.3. Turboprop engine configurations
CHAPTER 5. DESIGN FOR PERFORMANCE
5.1. Introduction
5.2. Initial weight prediction
5.2.1. Stages in the estimation of airplane weight
5.2.2. Examples of weight "guesstimates 11
5.3. Initial estimation of airplane drag
5.3.1. Drag breakdown
5.3.2. Low-speed drag estimation method
5.3.3. Compressibility drag
5.3.4. Retracing a drag polar from performance figures
5.3.5. Drag in takeoff and landing
5.4. Evaluation of performance requirements
5.4.1. High-speed performance
5.4.2. Range performance
5.4.3. Climb performance
5.4.4. Stalling and minimum flight speeds
5.4.5. Takeoff
5.4.6. Landing
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5.5. Aircraft synthesis and optimization
5.5.1. Purpose of parametric studies
5.5.2. Basic rules
5.5.3. Sizing the wing of a long-range passenger transport
5.5.4. Wing loading and thrust (power) loading diagrams
5.5.5. Optimization for low operating costs
5.5.6. Community noise considerations
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CHAPTER 6. CHOICE OF THE ENGINE AND PROPELLER AND INSTALLATION OF THE POWERPLANT 181
6.1. Introduction
6.2. Choice of the number of engines and the engine type
6.2.1. Engine installation factors
6.2.2. Engine failure
6.2.3. Engine performance and weight variations
6.2.4. Choice of the engine type
6.3. Characteristics, choice and installation of propellers
6.3.1. General aspects
6.3.2. Propeller coefficients and diagrams
6.3.3. Blade angle control
6.3.4. Propeller geometry
6.4. Installation of propeller engines
6.4.1. Location of the propellers
6.4.2. Tractor engines in the nose of the fuselage
6.4.3. Wing-mounted tractor engines
6.5. Installation of turbojet engines
6.5.1. General reqUirements
6.5.2. Fuselage-mounted podded engines
6.5.3. Wing-mounted podded engines
6.6. Miscellaneous aspects of powerplant installation
6.6.1. Thrust reversal
6.6.2. Auxiliary Power Units (APU)
CHAPTER 7. AN INTRODUCTION TO WING DESIGN
7.1. Introduction and general design requirements
7.2. Wing area
7.2.1. Wing loading for optimum cruising conditions
7.2.2. Wing loading limits and structural aspects
7.3. Some considerations on low-speed stalling
7.3.1. Stall handling requirements and stall warning
7. 3.2. Design for adequate stall chaz·acteristics
7. 3. 3'. Stalling properties of airfoil sections
7. 3. '4. Spanwise progression of the stall
7.4. Wing design for low-subsonic aircraft
7.4.1. Planform
7.4.2. Aspect ratio
7.4.3. Thickness ratio
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7.4.4. Wing taper
7.4.5. Airfoil selection
7.4.6. Stalling characteristics and wing twist 7.5. Wing design for high-subsonic aircraft
7.5.1. Wing sections at high-subsonic speeds
7.5.2. Wing design for high speeds 7.5.3. Low-speed problems of high-speed wings
7.5.4. Planform selection
7.6. High lift and flight control devices
7.6.1. General considerations
7.6.2. Trailing-edge flaps
7.6.3. Leading-edge high lift devices
7.6.4. Flight control devices
7.7. Dihedral, anhedral and wing setting
7.7.1. The angle of dihedral (anhedral)
7.7.2. Wing/body incidence
7.8. The wing structure 7.8.1. Types of wing structure
7.8.2. Structural arrangement in plan
CHAPTER 8. AIRPLANE WEIGHT AND BALANCE
8.1. Introduction; the importance of low weight
8.2. Weight subdivision and limitations
8.2.1. Weight subdivision
8.2.2. Weight limitations and capacities
8.2.3. Operational weights and the payload-range diagram
8.2.4. The choice of weight limits
8.3. Methodology of empty weight prediction
8.4. Weight prediction data and methods
8.4.1. Airframe structure
8.4.2. The propulsion group
8.4.3. Airframe services and equipment
8.4.4. Useful Load and the All-Up Weight
8.5. Center of gravity
8.5.1. The load and balance diagram
8. 5. 2. Loading flexibility and res.trictions
8.5.3. Effects of the general arrangement and ·layout
8.5.4. Design procedure to obtain a balanced aircraft
CHAPTER 9. PRELIMINARY TAILPLANE DESIGN
9.1. Introduction to tailplane design, control systems and stabilization
9.2. Static longitudinal stability and elevator control forces
9.2.1. Stick-fixed static stability and neutral point
9.2.2. Stick-free static stability and neutral point; the stick force
gradient
9.2.3. Stick-fixed and stick-free maneuver points and maneuver control
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forces
9.2.4. Reduction of control forces 313 9.2.5. Effects of compressibility and powerplant operation 316
9.3. Some aspects of dynamic behavior 317 9.3.1. Characteristics of the SP oscillation 317 9.3.2. Criteria for acceptable SP characteristics 319 9.3.3. A simple criterion for the tailplane size 320 9.3.4. The phugoid 323
9.4. Longitudinal control at low speeds 323 9.4.1. Control capacity required to stall the aircraft 324 9.4.2. Control capacity required for takeoff rotation and landing flareout 325 9.4.3. Out-of-trim conditions 326
9.5. Preliminary design of the horizontal tailplane 326 9.5.1. Tailplane shape and configuration 326 9.5.2. Design procedures 321
9.6. Design of the vertical tailplane 331 9.6.1. Control after engine failure: multi-engine aircraft 332 9.6.2. Lateral stability 335 9.6.3. Crosswind landings 338 9.6.4. The spin 338 9.6.5. Preliminary design of the vertical tailplane 339
CHAPTER 10. THE UNDERCARRIAGE LAYOUT 341
10.1. Introduction 342 10.2. Tailoring the undercarriage to the bearing capacity of airfields 343
10.2.1. Runway classification 343 10.2.2. The Equivalent Single Wheel Load (ESWL) 345 10.2.3. Multiple wheel undercarriage configurations 348
10.3. Disposition of the wheels 349 10.3.1. Angles of pitch and roll during takeoff and landing 349 10.3.2. Stability at touchdown and during taxying: tricycle under-
carriages
10.3.3. Gear length, wheelbase and track: tricycle undercarriages 10.3.4. Disposition of a tailwheel undercarriage
10.4. Type, size and inflation pressure of the tires 10.4.1. Main wheel tires
10.4.2. Nosewheel tires
10.4.3. Inflation pressure 10.5. Gear geometry and retraction
10.5.1. Energy absorption on touchdown
10.5.2. Dimensions of the gear 10.5.3. Gear retraction
CHAPTER 11. ANALYSIS OF AERODYNAMIC AND OPERATIONAL CHARACTERISTICS
11.1. Introduction
11.2. Terminology in relation to the determination of drag
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11.2.1. Pressure drag and skin friction drag
11.2.2. Wake drag, vortex-induced drag, and wave drag
11.2.3. Form drag, profile drag, and induced drag
11.2.4. Zero-lift drag and lift-dependent drag
11.2.5. Breakdown for drag analysis
11.2.6. Bodies with internal flow
11.3. Determination of aerodynamic characteristics
11.3.1. Reynolds number effects
11.3.2. Mach number effects
11.3.3. Low-speed polars
11.4. The flight envelope
11.5. Flight profile analysis and payload-range diagram
11.5.1. Operational climb
11.5.2. Cruise performance
11.5.3. Descent
11.5.4. Payload-range diagram and block time
11.6. Climb performance
11.6.1. Maximum rate of climb, time to climb and ceilings
11.6.2. Takeoff and landing climb
11.7. Airfield performance
11.7.1. Takeoff field length
11.7.2. Landing field length
11.8. Some aspects of operating economy
11.8.1. Economic criteria
11.8.2. Estimation of DOC
CHAPTER 12. EVALUATION AND PRESENTATION OF A PRELIMINARY DESIGN
12.1. Presentation of the design
12.2. External geometry and structural arrangement
12.3. Layout drawings
12.4. Conclusion
REFERENCES
APPENDIX A. DEFINITIONS RELATING TO THE GEOMETRY AND AERODYNAMIC CHARACTERI~TICS
OF AIRFOILS
A-1. General
A-2. Wing sections
A-2.1. Geometric definitions
A-2.2. Aerodynamic definitions
A-2.3. Nomenclature for some NACA sections
A-3. Wings
A-3.1. Wing planform
A-3.2. (Wing) twist and incidence
A-3.3. Aerodynamic definitions
References
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APPENDIX B. THE COMPUTATION OF CIRCUMFERENCES, AREAS AND VOLUMES OF CURVES,
SECTIONS AND BODIES 445
B-1. Fuselage 446 B-1.1. General method 446
B-1.2. Quick method for bodies of revolution 447
B-2. Wings and tailplanes 447
B-3. Fuel tank volume 448
B-4. Engine nacelles and air ducts 449
References 449
APPENDIX C. PREDICTION OF WING STRUCTURAL WEIGHT 451
C-1. Introduction 452
C-2. Basic wing structure weight 452
C-3. High lift devices, spoilers and speedbrakes 454
C-4. Wing group weight 454
APPENDIX D. THE WEIGHT PENALTY METHOD FOR FUSELAGE STRUCTURAL WEIGHT PREDICTION 457
D-1. Survey of the methodology 458
D-2. Gross shell weight 458
D-2.1. Gross skin weight 458
D-2.2. Gross stringer and longeron weight 459
D-2.3. Gross standard frame weight 459
D-3. Gross shell modifications 460
D-3.1. Removed material 460
D-3.2. Doors, hatches, windows and enclosures 460
D-4. Flooring 462
D-4.1. Passenger cabin and freight hold floors 462
D-4.2. Various other floors 463
D-5. Pressure bulkheads and frames 463
D-5.1. Pressure cabin bulkheads 463
D-5.2. Wheelbays for retractable undercarriages 463
D-6. Support structure 464
D-6.1. Wing/fuselage connection 464
D-6.2. Engine support structure 464
D-6.3. Other support structures 464
D-7. Additional weight items 465
References 465
APPENDIX E. PREDICTION METHODS FOR LIFT AND PITCHING MOMENT OF AIRCRAFT IN THE
EN ROUTE CONFIGURATION
E-1. Applicability of the methods
E-2. Contributions to the lift
E-3. Lifting properties of airfoil sections
E-3.1. The zero-lift angle
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E-3.2. Lift-curve slope
E-3.3. Maximum lift
E-4. Wing lift and lift distribution
E-4.1. Lift-curve slope
E-4.2. Spanwise lift distribution
E-4.3. Zero-lift angle
E-4.4. Maximum lift
E-5. Pitching moment of the wing
E-5.1. Aerodynamic center
E-5.2. Pitching moment (em ) ac w
E-6. Wing/fuselage interference effects on lift
E-7. Wing/fuselage pitching moment
E-7.1. Aerodynamic center
E-7.2. Pitching moment (em ) ac,wf
E-8. Nacelle and propeller contributions
E-9. Lift of the complete aircraft
E-9. l. Tailplane lift
E-9.2. Total trimmed airplane lift
E-9.3. Wing/body incidence
E-9.4. Trimmed lift curve
E-10. Airplane pitching moment and neutral point (stick fixed)
E-10.1. The stick-fixed neutral point
E-10.2. Horizontal stabilizer incidence
E-10.3. Pitching moment curve
References
APPENDIX F. PREDICTION OF THE AIRPLANE POLAR AT SUBCRITICAL SPEEDS IN THE
EN ROUTE CONFIGURATION
F-l. Drag components
F-2. Primary components of vortex-induced drag
F-2.1. Untwisted plane wings
F-3.
F-4.
F-2.2. Drag due to twist
F-2.3. Wing tip correction on vortex-induced drag
F-2.4. Vortex drag induced by fuselage lift
F-2.5. Nacelle contribution
F-2.6. Horizontal tailplane contribution
Profile drag of smooth, isolated major components
F-3 .l. The flat plate analogy
F-3. 2. Wing sections
F-3.3. Wings
F-3. 4. Fuselages and tail booms
F-3. 5. Engine nacelles
F-3.6. Tailplane profile drag
Subcritical interference effects and
F-4.1. wetted area corrections
F-4.2. Wing/fuselage interference
F-4.3. Nacelle/airframe interference
corrections
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F-4.4. Tailplane/airframe interference
F-5. Protuberances, surface imperfections and other extra's
F-5.1. Fixed undercarriages
F-5.2. Canopies and windshields
F-5.3. Wheel-well fairings and blisters
F-5.4. External fuel tanks
F-5.5. Streamlined struts
F-5.6. Powerplant installation drag
F-5.7. Excrescences, surface imperfections and other extra's
References
APPENDIX G. PREDICTION OF LIFT AND DRAG IN THE LOW-SPEED CONFIGURATION
G-1. Introduction
G-2. Effect of trailing-edge flap deflection on airfoil section lift G-2.1. General aspects
G-2.2. Lift increment at zero angle of attack
G-2.3. Maximum lift coefficient
G-2.4. Lift-curve slope
G-3. Lift of aircraft with deflected trailing-edge flaps
G-3.1. Wing lift
G-3.2. Various contributions
G-3.3. Contribution of the horizontal tailplane
G-4. Prediction of the low-speed drag polar
G-4.1. Profile drag
G-4.2. Vortex-induced drag
G-4.3. Trim drag
G-5. Leading-edge high-lift devices G-5. L Sections with plain leading-edge flaps
G-5.2. Sections with slats and Krueger flaps
G-5.3. Wing lift with leading-edge devices
G-5.4. Drag due to leading-edge devices
G-6. Drag due to extension of a retractable undercarriage
G-7. Ground effects
G-7.1. Ground effect on lift
G-7.2. Ground effect on drag
G-8. Drag due to engine failure
G-8. 1. Engine windmilling drag
G-8.2. Propeller drag
G-8.3. Drag due to the asymmetric flight condition
References
APPENDIX H. PROCEDURES FOR COMPUTING TURBO-ENGINE PERFORMANCE FOR AIRCRAFT
PROJECT DESIGN WORK
H-1. Scope of the method
H-2. The gas generator
H-3. Specific performance of straight jet engines
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H-4. Specific performance of turbofan engines 565 H-5. Thrust lapse rates, intake and exhaust areas of turbojet and turbofan
engines 566 H-6. Specific performance of turboprop engines 567 H-7. Cycle efficiencies and pressure losses 568 References 568
APPENDIX J. PRINCIPAL DATA OF THE US AND ICAO STANDARD ATMOSPHERES 571
APPENDIX K. THE DEFINITION AND CALCULATION OF THE TAKEOFF FIELD LENGTH REQUIRED FOR CIVIL TRANSPORT AIRCRAFT
K-1. Reference distance definitions K-2. Reference speeds K-3. Procedure for determining the takeoff field length K-4. Methods and data for the analysis of the takeoff
K-4.1. The ground run from standstill to Vx K-4.2. The ground run from v
X to VR
K-4.3. The rotation phase K-4.4. The airborne phase K-4.5. The stopping distance
References
INDEX
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574 576
578
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579
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581
563
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XV
Foreword
Since the education of aeronautical engineers at Delft University of Technology started
in 1940 under tae inspiring leadership of Professor H.J. van der Maas, much emphasis has
been placed on the design of aircraft as part of the student's curriculum. Not only is
aircraft design an optional subject for thesis work, but every aeronautical student has
to carry out a preliminary airplane design in the course of his study. The main purpose
of this preliminary design work is to enable the student to synthesize the knowledge ob
tained separately in courses on aerodynamics, aircraft performances, stability and con
trol, aircraft structures, etc.
The student's exercises in preliminary design have been directed through the years by a
number of staff members of the Department of Aerospace Engineering in Delft. The author
of this book, Mr. E. Torenbeek, has made a large contribution to this part of the study
programme for many years. Not only has he acquired vast experience in teaching airplane
design at university level, but he has also been deeply involved in design-oriented re
search, e.g. developing rational design methods and systematizing design information. I
am very pleased that this wealth of experience, methods and data is now presented in this
book.
In the last twenty years of.university education for engineers much attention has been
devoted to the fundamental sciences such as mathematics and physics. Recent years have
seen a revival of the interest in "design" and a number of general textbooks have now
been published on this subject. However, very few modern textbooks on the scienc~ and tne
art of aircraft design, are available. It is my sincere hope that Mr. Torenbeek's book
will contribute to a renewed interest in airplane design in many parts of the aeronauti
cal world, both inside and outside universities.
In view of the immense increase of knowledge in the aeronautical sciences and engineering
since the Second World War, it seems a formidable task, requiring much courage on the
author's part, to write a textbook on airplane design. It is well-nigh impossible to deal
with all problems of airplane design at the same depth and undoubtedly personal choice
has to prevail in many areas with regard to the material to be presented. In my view, Mr.
To.renbeek has made an excellent choice of his subjects, preserving a careful balance be
tween the presentation of a design manual and a general textbook on airplane design.
This volume will therefore be a most worthwhile guide to everybody who in the course of
XVI
his professional training or c;areer, is interested in the initial design phase of air
plane projects, an activity which is very important for shaping the future of aviation.
Delft University of Technology H. Wittenberg
August 1975 Professor of Aerospace Engineering
XVII
Author's preface
This textbook is intended to of·fer readers with a professional interest in airplane
design a general survey of the layout design process. It contains a large amount of
data and numerous methods which will be useful for carrying out the initial design calculations associated with the dimensioning of all major airplane parts. To a certain ex
tent it has the character of a design manual, but considerable attention is also devoted
to qualitative background information.
Several of the design methodologies and procedures presented have already appeared in the
literature on the subject, while others have been developed recently by the author. They
have been chosen on the basis of two criteria: they are not overdependent upon the state
of the art and they give reliable results with a minimum of information. Most of the
procedures have been extensively tested and considerably improved during the decade for
which the author was responsible for students' design courses and projects in the Depart
ment of Aerospace Engineering of the Delft University of Technology. Emphasis is laid
on conventional subsonic airplane designs in the civil category, i.e., broadly speaking
the airplane types to which the American FAR Parts 23 and 25 and equivalent BCAR requir~
ments apply (light and transport-type aircraft). Although many of the aspects to be dis
cussed are equally relevant to V/STOL and military aircraft, other complicati.ng factors
are involved in the design of these types, resulting in a radically ·different approach
to the design process. The large variety of design specifications and configurations in
these categories prohibits a general treatment.
The author makes no apology for the fact that his approach to airplane design may be
biased by a university environment, probably not the ideal one in which to carry out de
sign studies. The teaching of design in the aeronautical departments of universities and
institutes of technology has, unfortunately, not kept pace with developments in industri
al design practice. Aircraft design and development have become a matter of large in
vestments, even in the case of relatively small projects. The manhours required have in
creased considerably in recent years and the time is almost past when a single designer
could consider himself the spiritual father of a new type.
In contrast with the increased sophistication to be observed in industrial design very
few regular design courses at technological universities and institutes have been able to
survive the process of continuous curriculum evaluation and revision.
Although experienced designers in the industry may possibly be_the only authors qualified
to write an authoritative textbook on airplane design, they are usually not in a position
to devote enough of their time to a task which is not felt to be in the direct interest
of their employers. The reader may therefore conclude that the present book will be most
XVIII
useful for teaching and study purposes and for people who need a general introduction to
the vast field of initial aircraft design and development, Nevertheless, some of theprocedures and data presented will certainly be of some assistance to design departments in industry.
A knowledge of the principles of applied aerodynamics, airplane structures, performance, stability, control and propulsion is required to derive the utmost from this book. Its
usefulness for degree design courses will therefore be greatest in later stages of the
course. In the presentation of the individual subjects the need to balance design con
siderations is frequently stressed. This is particularly the case in the second chapter,
where the initial choice of the general arrangement is discussed, the basis adoptedbeing a synthesis of many considerations of widely differing character. The main body of the
book is devoted to the rationale behind layout de~ign and although estimation methods for
lift, drag, geometry, etc. are considered essential parts of the design process, they
have been brought together in a separate set of appendices with a limited amount of text. Considerable attention is devoted in all the chapters to the impact of airworthiness re
quirements on design and to subjects that have· been covered only very briefly by other authors. Particular emphasis is laid on the interior layout of }he fuselage (Chapter 3),
a survey of the present and future potentials of aircraft engines (Chapter 4), system
atic design studies based on performance requirements (Chapter 5), and weight estimation
methods (Chapter 8). The complex interaction of wing location, center of gravity range,
and horizontal tailplane design is treated in Chapters 8 and 9. The consistentcollection
of prediction methods for lift, drag and pitching moment estimation will, it is thought,
be useful as a general survey and as a tool for wing design (Chapter 7) and performance
calculations (Chapter 11). A large collection of statistical data, illustrations and diagrams is added to this presentation, which aims at providing the individual student/
designer or the small design team with reliable guidelines. For industrial applications some of the methods may have to be refined and/or extended.
A large and systematic list of references to literature is presented, which will help the
reader to find more information on the subjects specifically dealt with and on other re
lated subjects. As he glances through these references the reader's attention may be
drawn to a particular subject that interests him, possibly stimulating him to add another
innovation to the design synthesis of his project and thereby contribute to the overall quality of aircraft design technology.
ACKNOWLEDGEI~ENTS
As is the case in the preparation of most technical books, the author of this volume
is indebted to many persons who have aided in its completion.
For many years Professor H. Wittenberg has been the promotor of courses. in preliminary
aircraft design, and the idea of writing this book came about as a direct consequence
of his activities. The author wishes to express his appreciation to him for his general support, for his critical revision of the text and for his willingness to write the
foreword.
I am indebted to Mr. G.H. Berenschot, who has given general and technical assistance
by collecting information and data, preparing many figures and tables, compiling the
index and revising the text in detail. His perseverance, friendship and the moral support
he has given me for many years have been particularly invaluable.
I would like to express my appreciation to Professor J.H.D. Blom, chief aerodynamicist,
and Ir. P.F.H. Clignett, preliminary design engineer, both of Fokker-VFW International
XIX
as well as to Ir. C.H. Reede, head of the scientific department of the Royal Dutch Air
lines (KLM), and to my colleagues Ir. F.W.J. van Deventer and Dr. Th. van Holten, who
provided valuable and detailed suggestions together with actual text after reading
parts of the book for their technical content. In addition, many students have used
forerunners of the present text during their studies and their useful feedback has
resulted in many improvements.
Thanks are due to the Department of Aeronautics and Space Engineering of Delft
University of Technology for granting permission to prepare and publish this book, and
for providing the necessary typing and duplication facilities. Many members of this
Department and of the Photographic Office of the Central Library have given professional
help in producing the illustrative material. I am also indebted to the Delft University
Press, and in particular to Ir. P.A.M. Maas and Mrs. L.M. ter Horst-Ten Wolde for their
support, encouragement and assistance in editing the publication.
The author wishes to express his gratitude to Messrs. J. van Hattum, J.W. Watson M.A.,
and D.R. Welsh M.A., who have made admirable contributions to the translation of the
Dutch text and to improving the readability of the book. I am extremely indebted to
Mrs. C.G. van Niel-Wilderink, for the excellence with which she performed the formidable
task of typing not only the manuscript, but also the final copy for photoprinting. I
would like to thank my uncle, the Rev. E. Torenbeek, for his painstaking efforts in
checking the typographic accuracy of the copy, and mr. P.K.M. De Swert for preparing
the final layout and for his methodical checking.
The following individuals, companies and organizations have kindly provided data and
drawings.
Advisory Group for Aerospace Research and Development: Figs. 5-24, 10-1, 10-2, 10-3,
F-17 and F-22;
American Institute of Aeronautics and Astronautics: Figs. 2-1, 4-39, 7-20, 6-1, 9-11,
10-5, F-12 and G-25;
Aeronautical Research Council: Figs. 2-24, G-16, G-17 and K-6;
Aerospatiale: Figs. 2-3, 2-10 and 7-25;
Airbus Industries: Figs. 11-5 and 11-9;
Aircraft Engineering: Figs. 3-1, 3-11, 3-21, 3-26, 6-16, 7-25, 10-17, 10-16, 12-3 and
12-5;
Alata Internazionale: Fig. 2-3; The Architectural Press Ltd.: Fig. 3-6;
Avco Lycoming: Fig. 4-14;
Aviation Magazine: Fig. 2-8;
Avions Marcel Dassault-Breguet Aviation: Figs. 3-3, 3-11 and 10-20;
Boeing Aircraft Company: Figs. 2-11, 2-15, 3-11, 5-18, 7-25 and 10-6;
Mr. S.F.J. Butler: Fig. F-22;
Canadair Limited: Fig. 3-21;
Canadian Aeronautics and Space Institute: Fig. 3-27;
Centre de Documentation de l'Armement: Figs. 2-5 and 10-21;
The De Havilland Aircraft of Canada Ltd.: Fig. 3-11; Detroit Diesel Allison Division of General Motors Corporation: Fig. 4-46;
Dowty Group: Fig. 6-27;
Engineering Sciences Data Unit Ltd.: Figs. F-23, G-26 and K-9;
Flight Control Division of U.S. Air Force Flight Dynamics Laboratory: Figs\ A-2, A-3, E-3
and E-9;
Fokker-VFW International: Fig. 11-14;
XX
Flight Interna~ional: Figs. 2-2, 2-10, 2-11, 3-8 and 7-30;
Hamilton Standard Division of United Technologies Corporation: Fig. 6-5;
Hartzell Propeller Inc.: Fig. 6-7;
Hawker Siddeley Aviation: Figs. 2-20, 3-21, 12-2 and 12-4;
International Civil Aviation Organisation: Figs. 10-4 and 10-5;
De Ingenieur: Fig. 5-22;
Institute of Aerospace Sciences: Fig. 6-24;
Lockheed Aircraft Corporation: Fig. 3-17;
McDonnell Douglas Corp.: Figs.3-14, 6-2, 7-25;
McGraw-Hill Book Cy.: Fig. 6-19;
Messerschmitt-Bolkow-Blohm: Fig. 2-7;
(British) Ministry of Aviation: Fig. 10-6;
National Aeronautics and Space Administration: Figs. 2-25, 6-5, 7-5b, 7-22, 9-8, E-2,
E-5, E-6, G-11, G-12, G-19 and G-22;
National Research Council of Canada: Fig. 3-27;
Pergamon Press: Fig. 5-11;
Mr. D.H. Perry: Fig. K-6;
Piper Aircraft Corporation: Fig. 4-10;
Polytechnisch Tijdschrift: Figs. 2-10 and 7-25f;
Pratt and Whitney Aircraft Division of United Technologies Corp.: Fig. 4-46;
The Royal Aeronautical Society: Figs. 1-1, 2-14, F-6, F-22 and K-8;
Rolls Royce 1971 Ltd., Derby Engine Division: Figs. 4-15, 4-19, 4-20, 4-37, 4-46 and
6-25;
Dr. W. Schneider; Figs. C-2 and C-3;
Ir. G.J. Schott Jr.: Fig. 5-22;
Society of Aeronautical Weight Engineers: Figs. 11-7 and D-1;
Society of Automotive Engineers, Inc.: Figs. 4-7, 4-8, 4-9, 6-2, 6-7, 6-23, 6-27, 7-5
and 11-13;
Mr. W.C. Swan: Fig. F-17;
Turbomeca Bordes: Fig. 4-46;
Vereinigte Flugtechnische Werke-Fokker Gmbh: Fig. 3-11;
Mr. R.E. Wallace: Fig. 5-24;
John Wiley and Sons Ltd.: Fig. F-8.
Finally, I would like to thank my wife, Nel, for her unstinting help without which this
book would hardly have been possible.
September 1975 Ir. E. Torenbeek
Delft University of Technology
UNITS
In accordance with the convention used in publications such as Jane's All the World's Aircraft and Flight International, all data and most of the figures have been given in
the technical unit system, both in British and metric units. Hence, lb and kg refer to
pound and kilogram forces, respectively. An exception is made in Appendix J, where sea
level data of the Standard Atmosphere have been given both in the technical and SI systems.
XXI
Preface to the student Edition
Textbooks on the rapidly advancing subject of aircraft design tend to become obsolete within a few years. In spite of this the first edition has proved its value up to the present time, as a reference source for design efforts and publications in many places all over the world. It therefore pleases me that the publishers have decided to launch this new edition, aimed at an expansion of the market into the university classroom, thereby making the book affordable by many more individuals. This has given me the opportunity to further refine some of the methods and formulations, mainly on the basis of suggestions and comments of attentive students. In spite of the reduction in size, the contents are not abbriviated.
Delft, May 1981 E. Torenbeek
XXII
