What happened
On May 18, 2002, at approximately 07:20 UTC, a Hughes Schweizer 269 C helicopter, registration F-GJYZ, was engaged in aerial spraying operations in Vauciennes, France. After completing its first rotation of spraying over a vineyard, the pilot began a return flight at a very low altitude to a refueling truck located roughly 700 meters away.
While ascending a hillside, the aircraft struck a medium-voltage power line. The cables, which were positioned at a height of approximately six meters, were severed upon impact. One cable became wrapped around the main rotor mast, and the resulting tension caused the helicopter to be jerked backward before it crashed into a vineyard below. The impact resulted in the death of the pilot and the destruction of the aircraft.
The investigation
Investigators examined the wreckage and the site, noting that the three cables of the power line had been broken. The main wreckage lay 30 meters below the power line, with significant damage to the left side of the airframe and the tail boom separated from the fuselage. Evidence of electrical arcing was found on the metal pillars, and traces of the power lines were found on the windshield and wrapped around the rotor mast.
Witnesses at the scene reported hearing a loud noise and seeing blue sparks at the moment of impact. An agricultural worker noted that the pilot had appeared to be flying cautiously during previous maneuvers. The investigation also reviewed the pilot's recent flight history, noting that he had flown for over seven hours the previous day and had performed several spraying operations in the days leading up to the accident.
Findings
- The pilot was flying at an extremely low altitude that did not provide sufficient clearance for obstacles and deviated from established operational practices, which typically involve flying higher during transit.
- The pilot failed to perceive the power lines, despite having flown over the area earlier that morning and having performed a ground reconnaissance of the sector in April.
- The visibility of the cables was likely compromised because, at a height of only six meters, the wires blend into the green background of the vegetation.
- Accumulated fatigue from several days of intensive spraying operations may have contributed to a momentary lapse in vigilance.