What happened
On January 5, 2016, a Piper PA-25-235 aircraft, registration PR-OTJ, was performing an agricultural spraying operation near Campo Florido, Minas Gerais. The aircraft was departing from an improvised dirt runway located at the Usina Corurately plantation to distribute fertilizer.
During the takeoff roll, the pilot lost directional control, causing the aircraft to veer left and exit the runway into the plantation area. As the aircraft left the prepared surface, it encountered a 40cm depression at the edge of the runway. This impact caused the right wingtip to strike the ground and resulted in damage to the right landing gear and the spraying equipment. The pilot escaped the incident uninjured.
The investigation
CENIPA investigators examined the mechanical integrity of the braking system following the loss of control. Laboratory analysis of the right pedal's brake drum support shaft revealed that a tube had been welded to a bolt. The investigation determined that this weld failed due to overload. The laboratory findings highlighted poor-quality materials, an artisanal manufacturing method, and the use of improper welding processes.
Additionally, scanning electron microscopy of the pedal actuation linkage identified fatigue marks, though the exact origin of the fatigue could not be determined due to existing corrosion and deformation. While the maintenance provider stated they only replace components entirely rather than repairing them, the origin of the substandard weld could not be identified. The investigation also noted that the runway used for the operation was a dirt track also used by heavy plantation trucks, which had created a significant height difference at the runway margins.