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Through the use of an 'integrated product team' approach and new inspection techniques incorporating the latest in imaging capabilities and automation, the costs of some man- power intensive tasks can now be drastically reduced. Also, through the use of advanced eddy current techniques, the detectable size of cracks under flush-head fasteners can be reduced while maintaining a reliable inspection. Early in this decade, the FAA Technical Center and NASA LaRC formulated an aging aircraft research plan. The unique aspect about the research is that it is driven by the aircraft manufacturers and airlines in order to center only on those areas in which help is needed and to keep it focused. Once developed, the manufacturer works with the FAA Validation Center at Sandia National Labs., the airline, and the researcher to transfer technology to the field. This article describes the evaluation and results obtained using eddy current technology to determine the minimum detectable crack size under installed flush-head fasteners. Secondly, it describes the integrated efforts of engineers at McDonnell Douglas Aerospace and Northwest Airlines in the successful application of MAUS eddy current C-scanning of the DC-10 circumferential and axial crown splices. The eddy current C-scanning greatly reduced the man-hour effort required for the existing radiographic inspection. Thirdly, it describes the use of a novel ultrasonic technique coupled to a scanner and graphics for the detection and quantification of corrosion thinning and stress corrosion cracking of the DC-9 lower wing tee cap. This successful effort resulted from a rather large integrated task team. It also results in a vast man-hour savings over the existing internal visual inspection.
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