As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TRANSMISSION DISASSEMBLED FOR OVERHAUL. PERFORMED MAGNAFLUX INSPECTION OF MAST FOLLOWING STRUCTURAL FAILURE OF ANOTHER MAST IN ANOTHER AIRCRAFT. FOUR INCH CRACK INDICATION FOUND BEGINNING AT DOWEL PIN HOLE TO UNDERCUT IN MAST BASE THEN UP MAST THROUGH BEARING MOUNT AREA. AIRCRAFT HAS BEEN LOGGING FOR THE LAST 1,210 HOURS.