As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING RECEIVING OF NEW ACFT FOR CONTRACT COMPLIANCE VERIFICATION DISCOVERED UP ELEVATOR CABLE TO ELEVATOR BELLCRANK ATTACH BOLT NUT (CASLTELLATED NUT) MISSING COTTER KEY. NUT WAS STILL PRESENT BUT APPEARED TO HAVE "BACKED OFF" 1 TO 1.5 TURNS.