What happened
On December 23, 2019, at approximately 19:00 UTC, an Neiva EMB-201A, registration PT-GYR, was performing agricultural spraying operations near Arroio Grande, Rio Grande do Sul. The aircraft had departed from a local landing strip at Fazenda Olavinho to conduct a local flight over rice crops.
During the first pass over the field, the pilot reported a sudden sensation of the aircraft sinking. Upon noticing power lines ahead, the pilot attempted to apply power and climb; however, the aircraft failed to respond effectively. The aircraft continued its descent, passing over the power lines before colliding with the ground. The impact resulted in substantial damage to the aircraft, though the pilot sustained only minor injuries.
The investigation
CENIPA investigators examined the aircraft's engine, propeller, and maintenance records. While the engine structure showed no internal evidence of mechanical failure, analysis of the fuel servo revealed that the fuel flow was below the manufacturer's minimum specified limit. This deficiency resulted in a lean air-fuel mixture, which likely prevented the engine from maintaining sufficient power for a positive rate of climb.
Furthermore, the investigation revealed significant discrepancies in the aircraft's configuration. The instrument panel did not match the aircraft's serial number and was missing critical gauges, including oil pressure, oil temperature, cylinder head temperature, and fuel flow indicators. Additionally, the flap lever configuration was incorrect for this specific serial number.
Maintenance records for the airframe, engine, and propeller were also found to be outdated, lacking entries for monthly hours and scheduled inspections. The investigation also noted that the maintenance organization that performed the annual inspection was not certified to perform the specific engine services required.
Findings
- The fuel servo provided a fuel flow below the minimum required limit, causing a lean mixture and power loss.
- Inadequate maintenance oversight and failure to follow the recommended engine maintenance program.
- Lack of management supervision regarding the airworthiness of the aircraft.
- The aircraft was operating with an incorrect instrument panel and improper flap configuration.
- Maintenance logs for the engine and propeller were not up to date.