As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PROPELLER HAD BLADE FAILURE AT THE 30 INCH STATION. DURING DISASSEMBLY, ALSO NOTICED THAT AT LAST ASSY, THE A4140 LOCKING PLUGS FOR THE BLADE RETENTION NUTS HAD NOT BEEN INSTALLED. AFTER FURTHER DISASSEMBLY, THE BLADE THAT HAD FAILED ALSO HAD A CRACKED BLADE RETENTION FERRULE.