What was found
FLIGHT 1090 MHT-RKD 25 NM FROM DESTINATION RIGHT OIL PRESSURE ANNUNCIATOR ILLUMINATED AND PILOT NOTED OIL PRESSURE AT 20PSI, TORQUE WAS 600 FT-LBS WITH BOTH INDICATIONS WERE FLUCTUATING. NO YAW NOTED. AT 4000FT PILOT REDUCED POWER FOR DESCENT AND RIGHT ENGINE LOST POWER. PILOT SHUT DOWN RIGHT ENGINE AND EXECUTED SINGLE-ENGINE LANDING WITHOUT INCIDENT. PRELIMINARY MAINTENANCE EVALUATION REVEALED THE ACCESSORY GEARBOX/REAR OF ENGINE OIL SOAKED. FURTHER EVALUATION DID NOT REVEAL THE SOURCE OF THE OIL LEAK. THE ENGINE WAS REMOVED FROM SERVICE AND SENT TO A REPAIR FACILITY FOR FURTHER EVALUATION AND REPAIR.