As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS FLYING WHEN RT ENGINE LOST ALL OIL PRESSURE. ENGINE WAS SECURED. MAINTENANCE DISCOVERED MISSING SUMP PLUG ON OIL SUMP. SUBMITTER STATED UNIT WAS NOT SECURED AT FACTORY. CHECKED LT ENGINE, PLUG WAS NOT SAFETIED. SECURED PLUG WITH SAFETY WIRE AND RELEASED AIRCRAFT FOR SERVICE.