What happened
On February 9, 2018, a PA-25-260 aircraft, registration PT-OQX, crashed while performing agricultural spraying operations over a soybean plantation at Fazenda Reunidas, near Ribeirão Cascalheira, Mato Grosso. The aircraft was operating as part of an aerial application service when it struck the ground in a steep, nose-down attitude. The impact resulted in substantial damage to the airframe, engine, and propeller, and the pilot sustained fatal injuries.
The investigation
CENIPA investigators examined the wreckage and the aircraft's maintenance history. While the engine was functional at the time of the crash, evidence from the propeller blades suggested a loss of power occurred during flight. Analysis of the fuel pump revealed internal corrosion, oxidation, and defective valves, which prevented the pump from maintaining necessary pressure.
Furthermore, investigators found maintenance tools, oil filters, and various hardware in the pilot's quarters, suggesting the pilot was performing his own maintenance. The investigation also noted that the aircraft was utilizing ethanol as fuel, but there were no records confirming that the necessary engine modifications or regulatory approvals (AEV) from ANAC had been implemented. Additionally, the pilot's agricultural, instrument, and single-engine land ratings were expired at the time of the accident.
Findings
- Engine failure: The fuel pump failed to provide adequate pressure due to internal degradation, contributing to a loss of engine power.
- Improper maintenance: Evidence suggested inadequate maintenance or the failure to perform required services, specifically regarding the engine's conversion for ethanol use.
- Loss of control: The aircraft's steep impact angle and low speed suggested a stall condition, likely caused by improper flight control inputs.
- Regulatory non-compliance: The pilot was operating with expired ratings, and the aircraft's logbooks and maintenance records were not up to date.
- Lack of emergency decision-making: The pilot did not attempt an emergency landing in the soybean field, which could have mitigated the impact severity.