What happened
On January 29, 1990, an EMB-210 aircraft, registration PT-GNF, operated by TKB Aviação Agrícola LTDA, was performing agricultural spraying operations over a rice crop at Granja Preciosa in Itaqui, Rio Grande do Sul. After completing several planned passes, the pilot decided to perform an additional, unplanned pass over a restricted area that had not been previously surveyed.
During the execution of this unauthorized pass, the aircraft struck the canopy of several eucalyptus trees. Following the initial impact, the pilot attempted to recover the aircraft by pulling up; however, the right flap detached and remained in the extended position. This created significant aerodynamic asymmetry. While the pilot was attempting a right-hand turn, the asymmetric flap caused the aircraft to roll violently to the left. The aircraft entered an uncontrolled inverted flight and ultimately struck a farm warehouse. The impact resulted in the total destruction of the aircraft and damage to a harvester and farm equipment located in the building. The pilot sustained severe injuries.
The investigation
CENIPA investigators examined the operational sequence, the mechanical state of the aircraft, and the pilot's experience. The investigation established that while the pilot was properly licensed and qualified for agricultural operations, this was his first flight in this specific EMB-210 model. The pilot was more accustomed to the E-201-A Ipanema, which possesses different performance characteristics.
Investigators also noted that the aircraft was utilizing a control stick from a different model (the 201-A) rather than the correct part for the 201 model. The investigation focused on the lack of mission planning, the decision to fly in an unverified area, and the impact of the wind conditions, which were recorded at approximately 15 knots from a quartering tailwind.
Findings
- Deficient planning: The pilot attempted an unplanned maneuver in an area he had not thoroughly inspected, leading to an unexpected encounter with obstacles.
- Negative transfer of experience: The pilot's familiarity with the higher-performance E-201-A model likely led to errors in calculating speed, distance from obstacles, and the necessary recovery profile for the current aircraft.
- Operational error: The decision to improvise a fourth pass without assessing the terrain and wind conditions contributed to the collision with the trees.
- Mechanical failure: The detachment of the right flap during the recovery phase caused the loss of control through asymmetric lift.