With the extensive analysis and flight testing that has been done on these parts, including strain gauged flight testing, the concern over whether or not the parts might be yielding is not a big one, although I don't totally discount your point. However, the question I'm asking is if a part is under non-yielding cyclic loads (including the residual stress), is there a possibility of the peen layer relaxing over time? Does anyone know of any other manufacturers that requires regular re-peen of parts?
