What happened
On April 6, 2022, at approximately 15:00 UTC, a Neiva EMB-201 agricultural aircraft, registration PT-GFI, crashed in a wooded area near Fazenda Toca da Onça, in Espigão D'Oeste, Rondônia. The aircraft had departed from a nearby landing strip for an agricultural spraying mission. During the operation, the aircraft struck trees before impacting the ground, after which a post-crash fire destroyed the airframe.
The pilot, who was fully qualified and held valid medical and aeronautical licenses, sustained fatal injuries. The investigation revealed that the aircraft's engine was not producing power at the moment of impact, and the pilot had attempted an emergency forced landing, evidenced by the jettisoning of the agricultural payload and damage to the left wing caused by tree strikes during a descending trajectory.
The investigation
CENIPA investigators examined the aircraft's maintenance records and physical components to determine the cause of the power loss. While the engine's internal components, such as the crankshaft and connecting rods, showed no signs of mechanical failure or lubrication deficiency, investigators discovered significant unauthorized modifications. The aircraft was equipped with winglets that were not certified by the manufacturer for this model.
Furthermore, while the aircraft's Certificate of Airworthiness (CVA) specified operation with AvGas, evidence suggested the aircraft was operating with ethanol (AEHC). The investigation found that the necessary regulatory procedures for converting the engine to ethanol had not been followed. Physical examination of the fuel system revealed corrosion and oxidation, likely due to improper preservation of the system when using ethanol. Additionally, the fuel inlet nipple of the fuel injection servo was found to be obstructed by debris from this corrosion.
Findings
- The aircraft had undergone unauthorized structural modifications involving the installation of uncertified winglets.
- The aircraft was operating with unapproved fuel conversion (ethanol) without following required regulatory instructions or manufacturer service bulletins.
- Corrosion within the fuel system led to the obstruction of the fuel injection nipple, contributing to a significant loss of engine power.
- Maintenance records for the airframe, engine, and propeller were not up to date.
- The pilot's attempt at a forced landing was hindered by the low altitude and the loss of engine power.