The NTSB issued five recommendations to the FAA stemming from an ongoing investigation of an uncontained engine failure on an Boeing 767 in Los Angeles. Two of the recommendations are classified Urgent. The incident occurred on June 2, 2006, when the high-pressure turbine (HPT) stage 1 disk in the left engine, a General Electric CF6-80A failed during a maintenance ground run. The Board is aware that, as a result of the LAX incident, the FAA has issued an airworthiness directive with a schedule for maintenance — removal, inspection, and reworking — of CF6-80 series HPT stage 1 disks beginning at 6,900 cycles.
The Safety Board, however, is proposing on an urgent basis
that the FAA require that the disks be immediately removed
for maintenance if they have been in service for more than
3,000 cycles since new or since the last inspection. This
significantly more stringent standard would not permit disks to remain in service without inspection beyond the earliest known number of cycles at which cracks have been detected or failure has occurred. (NTSB)