Rockwell S2R N4191X accident near De Smet, Idaho

Probable cause

The pilot's inadequate visual lookout, which resulted in his failure to maintain clearance from guy wires during an aerial application flight. Contributing to the accident was the pilot's reduced ability to see the guy wires due to sun glare.

NTSB analysis

During an aerial application flight to apply fungicide to a wheat field, the pilot was flying the airplane from west to east making a spray pass along the south edge of the field, which was bordered by powerlines. About 660 ft. from the west end of the field where the pilot started his spray pass, a set of guy wires originated from the top of one of the utility poles that supported the powerlines, extended about 65 ft. into the field, and ran directly perpendicular to and in line with the airplane's flight path. However, the pilot failed to maintain clearance with the guy wires, and the airplane's outboard right wing impacted the wires. The airplane subsequently veered right and impacted the powerlines, crossed a road that bordered the field on the south, and collided with a stand of trees. The airplane came to rest within the stand of trees about 490 ft. southeast of the initial impact point with the guy wires. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Given that the sun was very close to the horizon and would have been almost directly in the pilot's eyes as he attempted to avoid the guy wires, it is likely that sun glare contributed to his difficulty in maintaining clearance from the wires.

Text from the NTSB. Open the NTSB docket for WPR16FA120 for the full record.