The Sept. 30, 2017 Air France Airbus A380 flight was four hours into its journey from Paris to Los Angeles when the flight crew heard an explosion as the fan hub of the right outer engine (the No. 4 engine) separated into at least three parts, with debris striking the aircraft before falling to the ground.
Metal Fatigue Cited in Air France A380’s Uncontained Engine Failure
The final BEA report says ‘cold dwell’ fatigue phenomenon is widely misunderstood.