Schweizer 269C 1 accident near Jeanerette, Louisiana, August 3, 2016

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

The commercial pilot was completing a scheduled biweekly patrol of a series of intersecting pipelines. When the helicopter failed to arrive as scheduled, a search was initiated. The helicopter was located partially submerged in a remote, thickly wooded cypress swamp. The damage to the helicopter and to surrounding trees indicated that the helicopter was in a near-vertical descent with a nose-down attitude at impact. Examination of the helicopter and engine revealed no evidence of preimpact discrepancies or anomalies, and damage to the main rotor blades was consistent with the engine producing power at impact. Review of weather information revealed that there was a large thunderstorm complex in the area, but it did not extend over the accident site. The closest weather station, located about 18 miles from the accident site, was reporting visual flight rules to marginal flight rules conditions due to light rain and a broken-to-overcast cloud layer. Due to an overcast layer of high cirriform clouds over the accident site, it was not possible to determine if any low clouds were in the immediate vicinity of the accident site. The circumstances of the accident are consistent with a loss of control by the pilot. The reason for the pilot's loss of helicopter control could not be determined.

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.