What happened
On March 5, 2016, at approximately 07:40 local time, a Piper PA-25-235, registration CX-BRX-R, was performing agricultural spraying operations over a 70-hectare rice crop near Pueblo San Luis, Rocha. The aircraft was operating under visual flight rules (VFR) to apply fungicide, carrying 110 liters of fuel and 3-50 liters of product.
During the initial application pass, the pilot failed to clearly identify a high-voltage power line installation. The aircraft's main landing gear struck the uppermost wire, which serves as a lightning conductor. The impact caused the pilot to lose control, forcing the aircraft into a nose-down attitude. During the descent, the fungicide from the hopper dispersed across the windshield, further obscuring the pilot's vision. The aircraft struck the ground violently and subsequently collided with a perimeter fence, causing the aircraft to spin 90 degrees before coming to a halt. The impact caused the right main landing gear to separate from the structure and the left gear to retract due to the ground slide.
The investigation
The CIAIA investigation established that the aircraft was within its weight and balance limits at the time of the accident. The pilot, who was wearing a flight suit, helmet, and mask, evacuated the aircraft uninjured. The investigation examined the flight path, the presence of the electrical infrastructure, and the visibility conditions at the time of the event. The investigation also noted that while the pilot possessed a farm plan from a surveyor, this document did not include updated information regarding local obstacles such as the power lines.
Findings
- The primary cause of the accident was the failure to detect the high-voltage power lines during the approach to the spray run.
- The pilot's vision was significantly compromised during the critical phase of the accident when the fungicide payload coated the windshield.
- The available agricultural maps provided to the pilot lacked updated information regarding the presence and height of electrical obstacles.
- The impact with the wires caused significant damage to the propeller, engine, cowling, hopper, landing gear, and both wings, as well as damage to the electrical grid and perimeter fencing.