Cessna U206 accident near Atlantic Ocean, AO, April 15, 2016

The NTSB's narrative final · quoted from the NTSB record

The pilot reported that, before departing on the overwater cross-country flight, he performed a preflight inspection and noted that the engine oil quantity was full. He also performed an engine run-up before takeoff, during which no discrepancies were noted, and he specifically stated that the oil pressure was satisfactory. After takeoff, the flight proceeded toward the destination. About 20 minutes from the destination, the pilot noticed a sudden loss of oil pressure and saw smoke coming from the engine compartment. The engine subsequently lost power, and the pilot ditched the airplane into the ocean. The airplane sank in about 2,360 ft of water and was not recovered. Although the engine oil and oil filter were changed the day before the accident flight, no correlation could be made between that event and the reported loss of engine power. Because the airplane and engine were not recovered and could not be examined, no determination could be made as to the reason(s) for the sudden loss of oil pressure, smoke, and then subsequent total loss of engine power.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.