The assumed flaws for the slow crack growth type structure are described in Section 1.3.4.  Thus, an 0.050 inch corner flaw is assumed to exist at the critical fastener hole joining panel ­ and the splicing stringer, as shown in Figure 1.3.12.  For this example, it is assumed that a common drilling operation was employed to prepare the hole with the primary damage, and therefore the same size crack is assumed in both elements.  Also, as explained in Section 1.3.4, initial flaws equivalent in stress-intensity factor level to an 0.005 inch radius corner flaw shall be assumed to exist in each hole of each element in the structure, such as shown in Figure 1.3.12.

Figure 1.3.12.  Illustration of Initial Flaws for Structure Qualified as Fail-Safe Multiple Load Path