Joggles found in removed rivet shanks typically indicate what issue?

Joggles found in removed rivet shanks are indicative of partial shear failure. This condition occurs when the rivet does not shear off completely during its failure, leading to a joggle or deformation of the rivet shank. This scenario suggests that the rivet was subjected to excessive shear loads, which is beyond its designed capacity, causing it to deform rather than detach cleanly.

In the context of structural integrity, partial shear failure can result from overloading or improper distribution of forces on a joint. When examining rivet failures, the presence of joggles provides crucial feedback, indicating potential issues in the structural design or the loading conditions experienced by the aircraft component. Recognizing this helps in diagnosing structural problems and understanding the overall health of the airframe.

While issues like excessive corrosion, improper installation, and material fatigue can lead to different forms of failure, they do not specifically create the joggled appearance typical of partial shear failure in rivet shanks. Each of these other scenarios presents unique indicators and mechanisms by which they affect aircraft components.