Failure Mechanisms

· An aircraft fuselage is a light-weight pressure vessel that is subjected to pressurization cycles during each flight. Fatigue crack growth at stress concentrators can cause catastrophic fuselage de-pressurization.
· The diagram shows the rear pressure bulkhead of a JAL Boeing 747 SR that failed 8 years after a joint repair. The crash killed 520 people.
· The 2024-T42 bulkhead structure is 4.56 m in diameter with a 2.56 m radius of curvature . Rivets of 2017-T3 aluminum hold the structure together.

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