Related Resources: Design and Engineering General

Aircraft Airframe Structural Design

Machine Design Equation and Calculators
Structural, Statics Deflection and Stress Equations and Calulators
Static's Resources

Aircraft Airframe Structural Design
Practical Design Information and Data on Aircraft
616 pages
Michael Chun-Yung NIU

Premium Membership Required to view Document/Book 

Open: Aircraft Airframe Structural Design

This book is intended to advance the technical understanding and practical knowledge of both practicing engineers and students. The book represents several decades of data collection, research, conversations with different airframe specialists, plus the author's more than twenty years' experience in airframe structural design. In addition, the text is partly based on the author's lecture (Structures Symposium of Airframe Design) for the Lockheed Extension Education Program (LEEP). It is, therefore, equally useful to those with primary degrees in engineering fields as a reference for designing advanced structures.

From a structural standpoint, the book is intended to be used as a tool to help achieve structural integrity according to government regulations, specifications, criteria, etc., for designing commercial or military transports, military fighters, as well as general aviation aircraft. It can also be considered as a troubleshooting guide for airline structural maintenance and repair engineers or as a supplementary handbook in teaching aircraft structural design in college. Aircraft design encompasses almost all the engineering disciplines and it is not practical to cover all the information and data within one book. Instead, relevant references are presented at the end of each chapter so that the reader can explore his own personal interests in greater detail. This book does not cover basic strength of materials and structural (or stress) analysis. It is assumed that the reader already has this background knowledge.

This book is divided into a total of sixteen chapters and emphasizes itemized write-ups, tables, graphs and illustrations to lead directly to points of interest. The data can be used for designing and sizing airframe structures and, wherever needed, example calculations are presented for clarification. As technology continues to progress, basic technical data hold true, however, to suit today's design such as advanced composite structure some modification to the analysis may be required.

In preparing this book, it was necessary to obtain and collect vast amounts of information and data from many sources. (Information and data used in this book does not constitute official endorsement, either expressed or implied, by the manufacturers or the Lockheed Aeronautical Systems Company.) Sincere appreciation is given to the Technical Information Center of Lockheed Aeronautical Systems Company (LASC) for their gracious help. Thanks also to those who contributed to this book, my colleagues at LASC
and other specialists from various companies. Special thanks to Mr. Richard W Baker (Research and Development Engineer of LASC) for his valuable comments in reviewing most of the drafts. Also, I would like to express my appreciation to Mr. Anthony C Jackson (Composite Design Department Manager of LASC) for his comments on Chapter 14.0, Advanced Composite Structures; and to my daughter Nina Niu for her help with this book.

Lastly, it is my hope that this book, with its wide scope and information on the application of technology on aircraft structural design, will prove not only to be a valuable reference tool for designing sound airframes with structUral integrity but also as a "bridge" to carry over the valuable experience and knowledge from those who have retired from the aircraft industry to the next generation of engineers. However, any suggestions and comments for revision would be greatly appreciated by the author.

 

TOC

CHAPTER 1.0 GENERAL INFORMAnON 1
1.1 Introduction 1
1.2 Development Progress 3
1.3 Planning and Structural Weight 5
1.4 Computer Aid 6

CHAPTER 2.0 DESIGN FOR MANUFACTURING 11
2.1 Introduction 11
2.2 Engineer's Responsibility 12
2.3 Producibility 12
2.4 Maintainability 14
2.5 Tooling 15
2.6 Other Considerations 19

CHAPTER 3.0 AIRCRAFT LOADS 21
3.1 Introduction 21
3.2 Aeroelasticity 30
3.3 Flight Maneuvers 33
3.4 Basic Data 36
3.5 Wing Design Loads 53
3.6 Empennage Loads 59
3.7 Fuselage Loads 66
3.8 Propulsion Loads 67
3.9 Landing Gear Loads 69
3.10 Miscellaneous Loads 73
3.11 Example of An Airplane Loads Calculation 74

CHAPTER 4.0 MATERIALS 90
4.1 Introduction 90
4.2 Material Selection Criteria 95
4.3 Aluminum Alloys 101
4.4 Titanium Alloys 109
4.5 Steel Alloys 110
4.6 Composite Materials 112
4.7 Corrosion Prevention and Control 113

CHAPTER 5.0 BUCKLING AND STABILITY 118
5.1 Introduction 118
5.2 Columns and Beam-Columns 120
5.3 Crippling Stress 134
5.4 Buckling of Thin Sheets 137
5.5 Thin Skin-Stringer Panels 141
5.6 Skin-Stringer Panels 146
5.7 Integrally Stiffened Panels 155

CHAPTER 6.0 CUTOUTS 162
6.1 Introduction 162
6.2 Lightly Loaded Beams 165
6.3 Heavily Loaded Beams 173
6.4 Cutouts in Skin-stringer Panels 177
6.5 Cutouts in Curved Skin-stringer Panels 186
6.6 Fuselage Cutouts for Big Cargo Doors 204

CHAPTER 7.0 FASTENERS AND STRUCTURAL JOINTS 207
7.1 Introduction 207
7.2 Rivets 210
7.3 Bolts and Screws 214
7.4 Fastener Selection 218
7.5 Lug Design and Analysis 219
7.6 Welded and Adhesive Bond 227
7.7 Fatigue Design Considerations 230
7.8 Shim Control and Requirements 243

CHAPTER 8.0 WING BOX STRUCTURE 247
8.1 Introduction 247
8.2 Wing Box Design 251
8.3 Wing Covers 256
8.4 Spars 269
8.5 Ribs and Bulkheads 277
8.6 VYing Root Joints 282
8.7 Variable Swept Wings 288
8.8 Wing Fuel Tank Design 296

CHAPTER 9.0 WING LEADING AND TRAILING EDGES 303
9.1 Introduction 303
9.2 Leading Edges 326
9.3 Trailing Edges 335
9.4 Wing Control Surfaces 347
9.5 Fixed Leading and Trailing Edges 352
9.6 Design Considerations 355

CHAPTER 10.0 EMPENNAGE STRUCTURE 358
10.1 Introduction 358
10.2 Horizontal Stabilizer 363
10.3 Vertical Stabilizer 369
10.4 Elevator and Rudder 371

CHAPTER 11.0 FUSELAGE 376
11.1 Introduction 376
11.2 Fuselage Configurations 379
11.3 Fuselage Detail Design 380
11.4 Forward Fuselage 398
11.5 Wing and Fuselage Intersection 406
11.6 Stabilizer and Aft Fuselage Intersection 412
11.7 Fuselage Opening 417

CHAPTER 12.0 LANDING GEARS 430
12.1 Introduction 430
12.2 Development and Arrangements 442
12.3 Stowage and Retraction 449
12.4 Selection of Shock Absorbers 454
12.5 Wheels and Brakes 461
12.6 Detail Design 464
12.7 Testing 466

CHAPTER 13.0 ENGINE MOUNTS 471
13.1 Introduction 471
13.2 Propeller-driven Engine Mounts 475
13.3 Inlet of Jet Engines 478
13.4 Wing-pod (Pylon) Mounts 479
13.5 Rear Fuselage Mounts and Tail Mounts 487
13.6 Fuselage Mounts (Fighters) 489

CHAPTER 14.0 ADVANCED COMPOSITE STRUCTURES 492
14.1 Introduction 492
14.2 Composite Materials 500
14.3 Design 509
14.4 Structural Joint Design 520
14.5 Manufacturing 526

CHAPTER 15.0 FATIGUE, DAMAGE TOLERANCE AND FAIL-SAFE DESIGN 538
15.1 Introduction 538
15.2 Performance and Functions 543
15.3 Design Criteria and Ground Rules 547
15.4 Structural Life Estimation 548
15.5 Fail-safe Design 554
15.6 Detail Design 561
15.7 Sonic Fatigue Design and Prevention 567
15.8 Verification Tests 570

CHAPTER 16.0 WEIGHT CONTROL AND BALANCE 581
16.1 Introduction 581
16.2 Weight Prediction 585
16.3 Performance and Configuration Influences 590
16.4 Balance and Loadability 591

Appendix A: CONVERSION FACTORS (U.S. unit vs. SI unit) 599
Appendix B: LIST OF CUTAWAY DRAWINGS 602