As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN PERFORMING A 600 HR INSPECTION, THE MECHANIC NOTED, NO SAFETY WIRE PRESENT ON THE SCREWS SECURING THE SENDING UNIT TO THE TANK. THIS IS THE ACFT FIRST SCHEDULED 600 HR INSP. THIS DEFECT WOULD HAVE HAD TO OCCUR DURING THE ASSEMBLY PROCESS. A MORE COMPREHENSIVE QC PLAN IS NEEDED WHEN ASSEMBLING FLIGHT CRITICAL COMPONENTS.