Failure Mechanisms

· The fatigue crack propagated along the line of rivets. When it reached a critical size for fast crack propagation the bulkhead failed, cabin pressure was transferred to the vertical fin, destroying it and the hydraulic system actuating the rudder.

· The plot shows the fractional area between rivet holes that had undergone fatigue failure along the dominant fracture direction (L18).
· A study of the crack surface of the failure, and measuring the separation of the fatigue crack advance striations permitted the local stress to be estimated.

From: Suresh, "Fatigue of Materials,"
Cambridge (1991)