Event Overview
On 22 December 2000 at 15:11 UTC, a Eurocopter AS350 B3 helicopter, registration I-JOPS, collided with a power line near Mezzavia in the municipality of San Genesio Atesino, Bolzano Province, Italy. After striking the wires, the aircraft crashed into a rock face and then fell to the ground, catching fire in a ravine. The two occupants, the pilot and a company technician, died in the explosion.
Aircraft and Crew Information
The helicopter was a single-engine Eurocopter AS350 B3 powered by a Turbomeca Arriel 2B engine. It held a valid standard airworthiness certificate (No. 13989/a) and had undergone its last 100-hour inspection on 24 November 2000. The pilot, a 33-year-old Italian male, held a valid commercial helicopter pilot license and had accumulated 437 hours and 3 minutes of flight time as of 8 March 2000. On the accident day, he had flown 4 hours and 29 minutes prior to the incident.
Flight History
The flight began at 14:20 UTC when I-JOPS departed from the operator's helibase in Vipiteno (BZ) en route to Cima Plose. The purpose was to pick up two civil protection technicians working on a repeater station. After dropping the technicians off in the valley, the helicopter returned to San Genesio Atesino for concrete transport operations. Upon completing that task and refueling at a pad adjacent to State Road 508, the helicopter took off again to return to Vipiteno.
Accident Sequence
During the return flight, the helicopter struck two of the three conductors of the "Ponticino" power line, which connects the town of Vanga (Renon municipality) with Avigna (San Genesio municipality). The impact severed the main rotor and transmission, which fell to the ground. The fuselage, now uncontrollable, hit a rock face above the old road to Sarentino and plunged approximately 30 meters beyond the rotor, bursting into flames between the rock face and the Talvera stream.
The fuselage was almost entirely consumed by fire, with only the tail boom, anti-torque rotor, and landing skid with snow kit remaining partially recognizable. Engine components were found near the fuselage and on the opposite bank of the Talvera stream.
Investigation Findings
The investigation determined that the helicopter was airworthy with no mechanical issues. The pilot showed no signs of in-flight incapacitation. The power line, which had been in place for at least 20 years, was not marked on official 1:10000 maps held by the Bolzano Fire Department. Its towers were painted green to reduce visual impact, making them difficult to distinguish against the terrain. Weather conditions at the time were calm with excellent visibility (CAVOK).
The departure pad was located in a shaded valley area, but as the helicopter flew toward the valley exit, luminosity increased significantly. The power line was situated in this brightly illuminated region. Post-impact examination revealed rotor blade damage consistent with cable strike, and ENEL technicians confirmed the line's conductors showed signs of rupture and fraying.
Autopsies conducted approximately three hours after the event attributed the deaths to injuries sustained from the helicopter's explosion.
Probable Cause
The accident was caused by the helicopter's collision with the power line. The causal factor was the pilot's failure to see the electrical cables, which were not marked and whose towers were camouflaged green. It is likely that the pilot experienced glare or a temporary reduction in visual acuity due to the rapid transition from the shaded takeoff area to the bright region where the power line was located. The changing light conditions altered the pupil's adaptation time, leaving the pilot unable to execute a timely evasive maneuver.