What happened
On December 8, 2018, a Neiva EMB-202A aircraft, registration PT-UUE, was performing agricultural spraying operations near São Gabriel do Oeste, Mato Grosso do Sul. The aircraft departed from a landing strip at Fazenda Monte Azul for a routine application flight. Approximately forty minutes into the flight, the pilot experienced engine vibration and a loss of power.
In response to the engine malfunction, the pilot jettisoned the remaining agricultural product and selected a soybean plantation for an emergency landing. During the forced landing, the aircraft struck a small rise in the terrain and overturned. While the aircraft sustained substantial damage, including the engine and propeller assembly being torn from the fuselage, the pilot escaped the wreckage uninjured.
The investigation
CENIPA investigators examined the aircraft's maintenance records and physical condition. Although the aircraft held a valid Certificate of Airworthiness and was within weight and balance limits, investigators discovered significant discrepancies in the maintenance logs. Specifically, the right magneto and the fuel distributor unit installed on the engine did not match the part numbers recorded in the maintenance logs. This lack of documentation prevented the traceability of maintenance and inspections for these critical components.
Fuel samples collected from the right wing and the fuel filter were clear of solid contaminants. However, analysis of the fuel filter sample revealed that the fuel's density was slightly above the required specification, and the ethanol content was slightly below the standard. While laboratory analysis of the engine and propeller components found no direct evidence of mechanical failure, investigators could not rule out an unidentified malfunction due to the undocumented components found on the engine.
Findings
- The pilot was properly qualified with valid medical and agricultural ratings.
- The aircraft's engine and propeller showed no definitive signs of mechanical failure during laboratory testing.
- Discrepancies in maintenance records prevented the traceability of the right magneto and fuel distributor unit.
- The aircraft's logbooks for the airframe, engine, and propeller were not up to date.
- The fuel sample from the filter showed deviations in density and ethanol content from the required technical specifications.
- The pilot's execution of the emergency landing involved high kinetic energy, suggesting the landing was not performed with optimal technique.