Section 1.3.7.1.1. Initial Flaw Sizes Assumed to Result from Manufacturing
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