What does joggles in a rivet shank indicate?

Joggles in a rivet shank indicate partial shear failure. This phenomenon occurs when a rivet is subjected to loads that exceed its shear strength, leading to deformation along the shank that results in a joggle. A partial shear failure does not completely compromise the rivet’s ability to hold the structure together, but it signals a potential weakness that must be evaluated.

Recognizing joggles is critical in maintenance and inspection practices, as they can affect the overall integrity of the aircraft structure. It’s essential for technicians to understand the implications of joggles, as they can highlight areas that may require closer examination or repair before they progress to more serious failures.

The other choices do not accurately describe joggles in a rivet shank. Complete shear failure would result in the rivet being severed or disengaged completely, which is not represented by joggles. Excessive bolt torque relates to threaded fasteners rather than rivets, and improper installation typically manifests in different ways, such as misalignment or incorrect protrusion. Understanding these distinctions helps clarify why joggles specifically indicate a partial shear failure.