What was found
AIRCRAFT WAS FLYING FROM TULSA/SILOAM SPRINGS, 8 MILES FROM SILOAM SPRINGS AIRPORT, PILOT REPORTED THE ENGINE OIL PRESSURE WAS FLUCTUATING FROM ZERO TO 60 PSI. ENGINE THEN STARTED TO VIBRATE SEVERELY BEFORE ENGINE COMPLETELY STOPPED. UPON INSPECTION OF AIRCRAFT, FOUND THE OIL QUICK DRAIN MISSING WHICH OBVIOUSLY CAUSED ENGINE TO LOSE OIL PRESSURE. SUBMITTER STATED QUICK DRAIN INSTALLED DID NOT HAVE A PROVISION FOR SAFETY WIRE. (X)