Inspection of Subsurface Flaws around Fasteners on Aircraft

New technology is needed for nondestructive inspection (NDI) of defects in metallic components on aircraft. Small cracks and flaws in multilayer components near rivets and fasteners are a particular concern. Other problems include detecting and characterizing small defects in highly confined areas. An NDI technology capable of imaging deeply buried defects at various layers of a component under a variety of surface conditions would be ideal. Existing NDI technologies such as visible imaging, x-radiography and acoustic emission cannot provide the high resolution NDI needed to detect deeply buried defects and characterize their dimensions and depth in a material. RMD proposes a revolutionary new eddy current imaging technology based on magnetic imaging and eddy current mapping detect and characterize cracks, corrosion and other defects in multilayer metallic components. A 2-D, solid-state sensor array will generate magnetic images of eddy currents. Eddy current mapping allow the system to perform highly dependable NDI on multilayer components containing defects near fasteners and holes. The proposed NDI system will be portable, versatile and simple to operate. The proposed NDI technology will improve aircraft integrity and crew safety, improve readiness, and reduce the cost and complexity of inspections.