analysis methods and design practices for repairs
material and process selection and optimization, including surface preparation, lamination, and bonding processes, and specification infrastructure for bonded repairs
life prediction and inspection intervals for the repaired structure
maintaining the damage tolerance of the repaired structure
Another important issue in the maintenance of aging systems is the replacement of components that are fabricated using alloys and processes that are susceptible to deterioration, especially corrosion and SCC. Improvements in commercial aluminum alloys, tempers, process controls, and fabrication methods could be beneficial if guidelines were provided to the logistic centers for materials and process substitution decisions (including performance and cost tradeoffs). Commercial airframe manufacturers have been active in updating obsolete materials and process specifications in their core design and manufacturing practices and in their maintenance programs (Goranson, 1997).