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contents

Acknowledgments xiIntroduction xiii

C H A P T E R 1

Perspectives on Investigations and Investigators 1Basic Anatomy of an Accident and Its Reconstruction 1Why Are Aircraft Accidents Investigated? 3The Human Factors Aspect 3Requirements to Become an Investigator 4Generalists and Specialists 5“Heavy Iron” Versus Most General Aviation Investigators 6When Consultants/Experts Become Involved 7Space Is the Next Frontier 8

C H A P T E R 2

Back to Basics 9Physical Evidence Is King 9Close Calls 10One Piece at a Time 11The Scientific Method 12Nine-Box Matrix 12Consider Even the Absurd 15Consequences of Incomplete and Inaccurate Findings 17Summary of Lessons Learned 22

C H A P T E R 3

On-Scene Investigation 25Before the Investigation Team Arrived 26Basic Investigation Gear 27Safety Considerations 29Emotional Considerations 29

viii Contents

Accident Scene Documentation 30Wreckage Layout and Recovery 32Exemplar Aircraft Inspections 33Tips on Photo Documentation 33Occupant Injuries 36Witness Interviews and Statements 36Understanding the News Media 37

C H A P T E R 4

“Kickin Tin” 39Wreckage Distribution 39Airframe Structural Damage 41Cable-Driven Flight Control Trim Tab Systems 53Electric Motor-Driven Actuators 55Propeller Blade Impact Damage 56Turbine Engine Damage 59Cockpit Instrumentation 61Who Was Flying the Aircraft? 66Basic Failure Analysis of Metal 67Basic Composite Failure Analysis 70

C H A P T E R 5

Crashworthiness Analysis 73Implementing Crashworthiness Investigations 73Aircraft Design Expectations 74Crash Load Evaluation 76Using G-Load Survivability Limits to Look Deeper 83Emergency Egress Issues 87

C H A P T E R 6

In-Flight Breakups 89Behavior of Separated and Falling Parts 90Piecing the Wreckage Together 96Flutter 102Aircraft Performance 103Human Factors Causing Loss of Control 104

Contents ix

C H A P T E R 7

Mid-Air Collisions 109Pilot Awareness 109See-and-Avoid Issues 110Structural Impact and Scratch Marks 115

C H A P T E R 8

Fire and Explosions 121General Aspects of Aircraft Fires 121Post-Impact and Ground Fires 122In-Flight Fires 123Determining Origin of Fires 125Types of Aircraft Explosions 127Damage Caused by Detonation 128Damage Caused by Deflagration 129

Conclusion 131

Appendix A 133Aircraft Wreckage Reconstruction Terms 133

Appendix B 139Handy Numbers/Conversions/Equations 139

About the Author 143

Index 145