As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BEVEL REDUCTION GEAR LOST OIL PRESSURE WHEN AIRCRAFT LANDING ON OIL RIG. RELIEF VALVE UNSCREWED FROM BEVEL REDUCTION GEAR COMPLETELY CAUSING LOSS OF OIL PRESSURE. RETAINER TOO LARGE TO LOCK RELIEF VALVE PROPERLY, P/N 704A34-631-014. INSTALLED CORRECT RETAINER, P/N 23350AC160LE.