Static and Fatigue Characteristics of Hybrid Repairs in Primary Metallic Aircraft Structures

This thesis explores advanced joining techniques for primary metallic aircraft structures, focusing on hybrid and bonded joints to enhance airframe durability and longevity. It challenges traditional fastened joints, which have mechanical performance issues. The study examines joints representing thin and thick structural assemblies. Experimental and numerical analyses, alongside various NDI techniques, show that while both joint types perform well, hybrid joints mitigate undetectable defects, allowing for early damage detection and preventing catastrophic failure. They extend the average aircraft's lifespan by up to fourfold, significantly reducing repair costs and wastage, and improving aircraft availability. These findings pave the way for certification procedures for hybrid joints in primary aircraft structures.