What happened
On March 22, 2019, at approximately 11:40 UTC, a Robinson R4SSII helicopter, registration PR-DRL, was conducting an agricultural spraying operation in Cafezal do Sul, Paraná. The aircraft, operated by Copacabana Serviços Aéreos Especializados, had departed from a landing area at Fazenda São Pedro to apply fungicide to a crop.
During the first pass of the application, the aircraft struck an overhead electrical wire, which subsequently caused the helicopter to impact the ground. The impact resulted in substantial damage to the aircraft. The pilot, who was the sole occupant, escaped the accident uninjured.
The investigation
CENIPA's investigation focused on the flight planning and the pilot's assessment of obstacles. The pilot had previously identified the presence of the power line via ground observation during a reconnaissance of the area, estimating its height visually. During the flight, the pilot believed the aircraft's flight path was sufficiently high to clear the wire. However, the pilot did not see the wire during the pass and only became aware of the contact when the impact against the fuselage occurred.
The investigation also reviewed the aircraft's maintenance records. While the airworthiness certificate was valid, the engine and airframe logbooks had not been updated since February 2017. Additionally, due to a lack of documentation regarding the installation of the agricultural spraying equipment, investigators could not verify if the aircraft was within its proper weight and balance limits.
Findings
- Inadequate flight planning, as the risk of colliding with a known obstacle in the application area was not sufficiently mitigated.
- Inadequate pilot judgment regarding the required clearance height for the power line.
- The pilot was properly licensed and rated for the operation.
- The weather conditions were favorable for flight, with visibility exceeding 10km and calm winds.
Safety action
CENIPA issued a recommendation to the National Civil Aviation Agency (ANAC) to ensure that the maintenance organization responsible for the aircraft's spraying equipment installation follows established protocols for issuing weight and balance documentation for R44 aircraft.