Aircraft Fatigue Management (SpringerBriefs in Applied Sciences and Technology)

Acknowledgements 6 Contents 7 About the Author 9 1 Introduction 10 References 12 2 Fatigue Demystified 13 2.1 Important Aspects of FCG: An Illustrated Example 14 2.2 Analytical Descriptions of FCG: A Brief Summary 17 References 18 3 Some Design Considerations 20 3.1 Existing Airframe Design Standards 20 3.2 Conventional Fatigue Analyses 22 3.3 Constant Versus Variable Amplitude Loading 23 3.4 Relative Spectrum Severity 24 3.5 Individual Aircraft Fatigue Tracking 25 3.6 Full-Scale Fatigue Test Considerations 27 3.7 Residual Strength Criterion 28 3.8 Multiple-crack Fatigue Damage 29 3.9 Scatter in Fatigue Performance 30 References 32 4 Lead Cracks and an Example of Fatigue Lifing 34 4.1 Behaviour of Lead Cracks 34 4.2 Exponential FCG Generality and a Simplified LCFLF Lifing Method 36 References 38 5 Derivative Fatigue Crack Growth Models 40 5.1 The Cubic Rule 40 5.2 The Block-By-Block EBA Approach 41 5.3 The Modified Hartman–Schijve Equation 43 References 43 6 Fatigue-Nucleating Discontinuities 45 6.1 Discontinuity Sources 47 6.1.1 Equivalent Pre-crack Size (EPS) 48 References 49 7 Lead Crack Lifing Methodology 51 7.1 Comparison of Aircraft Design Standards 52 7.2 In-Service Detected Cracks 55 7.3 Probability of Failure 56 References 57 8 Fleet Management, Repair and Life-Enhancement Considerations 59 8.1 Fleet Management Considerations 59 8.2 Modifications and Repairs 60 8.3 Bonded Repairs 60 8.4 Cold-Working Repairs 63 8.5 Pitting Corrosion Management 64 References 66 9 Concluding Remarks 68