The operated on a flight from Bermuda to Lajes, Azores over the Atlantic Ocean. The flight continued normally, cruising at 11,000-ft. At 13:32Z a sudden power loss occurred on the starboard engine. The BMEP dropped from 145 to 70 and manifold pressure from 31″ to 17″. The pilot decided to return to Bermuda. At 13:52Z. as the aircraft was descending to 3000 ft, the starboard engine built up to 20″ manifold pressure and commenced severe backfiring. The propeller was then feathered. At 14:45Z while maintaining 3000 feet the port engine began smoking and throwing oil. The pilot diverted to Station Echo, weather observation station located in the Atlantic Ocean east of Bermuda. The aircraft ditched at 15:31Z. All crew members were quickly rescued by USCGC Coos Bay.