AD = 2 hour inspection when hub assembly failed at less than 25% of life limit cycles per previously linked article?
http://www.iba.aero/wp-content/uploa...e-May-2017.pdf
Similar fan disc failure some of us may remember.
Lessons Learned
The NTSB determined that the probable cause of this accident was the inadequate consideration of the human factors limitations in the inspection and quality control procedures used by the UAL engine overhaul facility. These limitations resulted in the failure to detect a fatigue crack originating from a previously undetected metallurgical defect located in a critical area of the stage 1 fan disk of the engine.