Bell Helicopter Textron Canada 407 N150AS accident near Laplace, Louisiana

Probable cause

The pilot’s failure to maintain clearance from power lines. Contributing to the accident was the pilot’s decision to fly in instrument conditions.

NTSB analysis

The pilot was operating the helicopter in an area of low cloud ceilings, fog, and mist. Flight data showed that the helicopter’s altitude varied and that the maximum altitude reached was 175 ft above ground level. The last recorded altitude was 75 ft. The helicopter subsequently collided with a guy wire suspended between two transmission line trusses and impacted the highway below. A postimpact fire ensued and destroyed the helicopter.

Postaccident examination of the airframe and engine revealed no anomalies that would have precluded normal operation of the helicopter. The pilot did not receive an official weather briefing before the flight. After the accident, a US Coast Guard pilot was deployed to the accident area. The Coast Guard pilot stated that a “wall of clouds” extended from the power lines westward to the accident area. Thus, the accident pilot likely could not see the power lines due to the reduced visibilities in mist and clouds at the accident time.

Text from the NTSB. Open the NTSB docket for CEN22FA073 for the full record.