What happened
On November 14, 2000, a G-164A agricultural aircraft, registered as PT-WOK, crashed while performing a urea spraying operation over a cornfield at Fazenda Furnas do Café in São Gabriel D’Oeste, MS. After departing from an uncertified runway, the pilot executed two 90-degree left turns to intercept the spraying swath. While maintaining an altitude of approximately 10 meters, the aircraft lost lift and collided with the ground, subsequently flipping onto its back.
The pilot sustained minor injuries, but the aircraft suffered extensive damage, including the loss of the vertical stabilizer and rudder, and severe damage to the engine, propeller, and fuselage.
The investigation
CENIPA's investigation revealed a series of severe regulatory and operational irregularities. The aircraft was operating with a suspended Certificate of Airworthiness and lacked any verifiable maintenance records. Furthermore, the airspeed indicator was inoperative, preventing the pilot from monitoring the aircraft's performance.
The investigation also highlighted significant personnel issues. Although the pilot held valid licenses, he was not qualified for this specific aircraft type, having completed only 10 minutes of flight time in the model two months prior without formal instruction. Additionally, the pilot was not an employee of the aircraft's owner, Oliveira Aviação Agrícola Ltda., but rather an employee of a different company, Serrana Aviação Agrícola Ltda., where the aircraft was being stored.
Findings
- Pilot Error: During the maneuver, the pilot reduced engine power and propeller RPM. In an attempt to recover from a loss of lift, the pilot mistakenly searched for flap controls—which do not exist on this model—and adjusted the fuel and propeller levers while failing to advance the throttle.
- Maintenance Deficiencies: The inoperative airspeed indicator and the lack of maintenance logs contributed to the pilot's inability to recognize the impending stall.
- Organizational Failures: There was a profound lack of safety culture within the operating environment. The pilot accepted a high-risk flight due to professional anxiety and a desire to maintain employment during the off-season.
- Regulatory Non-compliance: The flight was conducted using an aircraft with suspended airworthiness, an uncertified runway, and an unqualified pilot.