Flaws assumed to result from manufacturing and/or material conditions are specified in JSSG-2006 paragraph A3.12.2 for Fail Safe Structure.  The primary damage at a fastener hole (Figure 1.3.16) is an 0.05 inch corner flaw.  Since the drilling operation is common to the skin and splicing stringer, the 0.05 inch flaw must be assumed in both members.  Panel ­ is considered for this example because it was previously chosen to be the critical load path.  Note that only one primary damage site is assumed for each load path (e.g. along the path of expected damage, along a wing section).  Also, it is not necessary to consider the interaction of flaws from adjacent primary sites.  Each analysis of primary damage is conducted independently.  At each hole other than the assumed primary site, an 0.005 inch radius corner flaw is assumed to represent average or typical manufacturing quality.  The effect of interactions between the 0.005 inch flaws and the primary flaws must be considered when conducting the analysis.

Figure 1.3.16.  Initial-Flaw Assumptions for Example Case Qualified as Fail Safe