History of the Flight
The pilot, flying alone, departed from a private helicopter landing site for flights lasting approximately three minutes to spray opaque white paint onto six-meter-high polytunnels. After whitening the tunnels lengthwise in a northwest-southeast direction, the pilot continued spraying while flying overhead the tunnels in a southwesterly direction, starting along the edge of a main road bordered by a medium-voltage (MV) power line carrying 20,000 volts. At the end of the first pass, at the beginning of a left-hand turn for a second pass northeast, the pilot felt the helicopter's left skid catch on something. The helicopter, traveling at 45 to 50 knots, quickly decelerated. The pilot realized he had struck the cables of a power line. Two of the three MV cables broke; the third cable remained intact and caused the helicopter to roll inverted. The pilot could not regain control, and the helicopter collided inverted with the ground in a crop field about 50 meters from the road and 15 meters past the power line. The pilot shut down the engine and exited unaided, sustaining bruises and pains.
Additional Information
Site and Wreckage
The wreckage lay inverted. All damage resulted from striking the power line cables and colliding with the ground. One main rotor blade penetrated the canopy and cockpit on the left side. The tail rotor and a second main rotor blade were found near a pole of the MV line. One pole approximately 30 meters from the polytunnel served as the branch-off for the severed power line; another pole about 150 meters southeast carried the three cables. The power line ran nearly parallel to the polytunnels at a distance of about 30 meters. The left skid struck the cables at a height of about 7 meters, approximately 6 meters from the lowest point of the span. Two cables were severed. Around 2,300 people experienced a power outage.
Pilot Information
The 35-year-old pilot held a commercial helicopter pilot license (CPL(H)) since November 2011, a private airplane license (PPL(A)) since August 2011, and a glider pilot license (SPL) since January 2006. He obtained a type rating for the Schweizer 269C in July 2013, which was valid, as was his Class 1 medical certificate. A former French Army Light Aviation (ALAT) pilot, he had logged about 1,800 helicopter flight hours, two-thirds of which he stated were low-level flights. He was also the accountable manager of AIRAGRI since April 2023. He had accumulated about 150 hours in agricultural helicopter work. On the accident day, he flew 4 hours 20 minutes before the accident, completing 83 spraying rotations; the previous day he flew 5 hours 30 minutes for 86 rotations. The pilot had performed similar work on the polytunnels the previous month. He did not conduct a reconnaissance flight that day to identify hazards; he knew of both the MV power line along the polytunnels and the one from the branch-off pole but stated he had forgotten about the latter. He noted that the low-height converging path left no safety margin. He usually flew on parallel or divergent paths to avoid power lines. He explained that detecting the cables was difficult due to the sun facing him on the flight path and the cables being at the bottom of his field of vision with poor contrast against crops. He wore sunglasses. He sprayed at heights between 2 and 5 meters above the tunnels. When the helicopter inverted, he took a brace position and protected his face. After the accident, he undertook systematic reconnaissance of work sites, slower speeds for low-height work, and regular breaks to counter routine and fatigue.
Operator Information
AIRAGRI is a specialized operator approved by the French civil aviation safety directorate (DSAC), operating four Schweizer 269Cs for aerial photography and agricultural work. The company had a risk assessment and standard operating procedures (SOPs) meeting EU Regulation 965/2012. The SOPs required pilots to obtain information about obstacles and hazards before each flight, and noted that power lines are the biggest hazard, especially medium and low voltage lines whose cables may be low and pylons hidden. It advised prior systematic reconnaissance of each flight zone before deciding to fly low.
Meteorological Information
Estimated conditions at the accident time (about 16:20 local) from nearby weather stations included wind from 350° at 8 knots gusting 15 knots, visibility over 10 km, cumulus clouds 3-4/8 at about 5,000 ft, altocumulus 3-5/8 at about 8,500 ft, temperature 19°C, dew point 9°C, QNH 1018. The sun position at the site was azimuth 235° and elevation about 50°.
Conclusions
The helicopter struck the MV power line cables during a turn after spraying a polytunnel. The pilot had forgotten about the line. The pole carrying the three cables was on the pilot's left side and likely outside his field of vision. Detection was hampered by the sun facing him and poor contrast. Contributing factors included the lack of prior reconnaissance and possible overconfidence from experience and routine.