What happened
On March 6, 1990, an EMB-2/10-A operated by Agro Aérea Triângulo LTDA was performing agricultural spraying operations over a soybean plantation at Fazenda São Caetano, near Chapadão do Sul, Mato Grosso do Sul.
After completing a second low-level spray pass, the pilot initiated a turn to return for another pass. During this maneuver, the right wingtip of the PT-UAS struck low-voltage power lines. The impact caused the aircraft to enter a 180-degree longitudinal roll, leading to a subsequent impact with the ground in an inverted position. The aircraft was destroyed, and the pilot sustained fatal injuries.
The investigation
CENIPA investigators examined the aircraft's maintenance records and the pilot's credentials. While the pilot was experienced, with approximately 2,000 flight hours in this aircraft type and a decade of experience in agricultural aviation, his medical certificate (CCF) had expired.
The investigation also revealed that the aircraft's maintenance logs were not up to date, specifically regarding flight hour entries for the three months preceding the accident, and a required annual maintenance inspection (IAM) from 1988 had not been recorded.
Investigators evaluated several hypotheses regarding the cause of the collision. A potential engine failure was ruled out by eyewitnesses who reported no change in engine noise or smoke, and by the condition of the propeller, which was found to have impacted the ground at high RPM. The investigation focused on the pilot's lack of familiarity with the specific obstacles in the area and the lack of adequate mission planning.
Findings
- Deficient planning was the primary cause, as the pilot likely did not perform a thorough pre-flight survey of the area, leaving him unaware of the low-voltage wires.
- Deficient judgment contributed to the accident during the execution of the flight maneuver.
- Flight indiscipline was noted because the pilot operated with an expired medical certificate.
- The aircraft's maintenance documentation was incomplete and not up to date.
- The pilot's experience was sufficient for the mission, but the lack of obstacle recognition compromised the safety of the operational profile.