Sikorsky UH-34D N3880J accident near Wilton, Iowa

Probable cause

The inadequate performance planning by the pilot that resulted in reduced climb capability while transitioning to an out-of-ground effect hover with a left pedal turn.

NTSB analysis

The pilot flew the helicopter toward an agricultural field that was to be sprayed with fungicide. As the helicopter flew along the edge of the field, the pilot brought the helicopter into an out-of-ground-effect hover and performed a left pedal turn. The helicopter descended and impacted terrain. The helicopter was operated with a fuel grade that reduced the maximum engine power and the available climb rate for the conditions at the time of the accident. According to the Rotorcraft Flying Handbook, Basic Flight Maneuvers, Hovering Turn, it states in part, "…It should be noted that during a turn to the left, more power will need to be added because left pedal pressure increases the pitch angle of the tail rotor, which, in turn, requires additional power from the engine..." It is likely that the helicopter did not have sufficient power to perform the hovering turn successfully. A postaccident examination did not reveal any mechanical anomalies that would have precluded the helicopter's operation.

Text from the NTSB. Open the NTSB docket for CEN11FA507 for the full record.