What happened
On January 7, 2015, an Airbus Helicopters AS350 BA, registered F-GHBR, was conducting a medium-voltage power line inspection flight south of Tulle. Operated by Jet System Hélicoptères Service (JSHS), the aircraft was flying at approximately 30 knots, positioned parallel to and above the target power lines. During the mission, the lower portion of the helicopter struck a converging medium-voltage line that intersected the path of the line being inspected. The impact caused two of the three cables to break. The pilot performed a precautionary landing in a nearby field, and no injuries were reported among the three crew members on board.
The investigation
The investigation focused on the crew's ability to identify obstacles during the inspection. While the specific power line involved in the collision had been identified as a known obstacle during pre-flight preparations, the crew failed to detect it prior to the impact. The investigation noted that the navigator, whose responsibilities included monitoring the forward and left sectors for obstacles, was in training at the time of the incident. Following the event, the crew conducted an immediate on-site inspection of the Airbus Helicopters AS350 BA, finding only superficial scrape marks. After a successful stationary hover check, the aircraft was flown to Issoire for a more comprehensive technical inspection following manufacturer guidelines.
Findings
- The primary cause of the incident was the failure to detect the converging power line before impact.
- The navigator was undergoing training during the flight, which may have affected the effective monitoring of the flight path.
- Meteorological conditions were not a contributing factor to the collision.