For decades, cold working has been used to extend the fatigue life of aircraft fastener holes. This procedure may be a terminating action or used to extend the inspection interval/lifetime. To have confidence in the process, aircraft maintainers need an inspection tool to conclusively determine: 1.) that cold working has been applied to a hole and 2.) that the results are within specifications.

TRI Austin has developed a prototype tool, the FastenerCam™, to perform this inspection of cold expanded aircraft fastener holes. In addition to examining the fastener geometry, including the diameter, countersink angle, depth, and alignment, the FastenerCam™ measures and correlates the vertical deformation around the hole to the degree of expansion. Its capabilities are being extended to include countersunk holes, and the system was redesigned for ruggedized handheld use, permitting work in tight spaces. TRI Austin continues to expand the FastenerCam™’s use cases to holes cold expanded through multiple plate layers, asymmetrically expanded holes, and countersunk holes expanded using Fatigue Technology Inc. (FTIs) countersink specific toolset. TRI Austin’s ruggedized manufacturing prototype will permit this technology to be rapidly brought to market after project completion.