What happened
On March 13, 2012, a Neiva EMB-201, registration PT-GGG, was performing an agricultural spraying operation over a soybean plantation near Júlio Cardoso, in the municipality of Espumoso, Rio Grande do Sul. The aircraft had departed from an improvised landing strip to apply chemical products to the crops.
During the fourth application pass, the pilot experienced a sudden loss of engine power. Due to the low altitude of the flight at the time of the failure, the pilot was unable to restart the engine and was forced to perform an emergency landing in the soybean field. The aircraft sustained substantial damage to the engine, but the pilot emerged uninjured.
The investigation
The investigation focused on determining the cause of the power loss. Fuel samples taken from the aircraft were analyzed by the Institute of Aeronautics and Space (IAE), which confirmed that the fuel was in proper condition and showed no contamination or issues.
Technical inspections of the engine were conducted by a specialized maintenance company. The examination revealed that the fourth cylinder had detached from the engine block during flight. Further analysis of the engine components showed that the studs used to secure the cylinder to the engine block had failed in a gradual manner.
Findings
- The primary cause of the engine failure was the detachment of the fourth cylinder during flight.
- The failure was triggered by the breakage of the cylinder studs that secure the cylinder to the engine block.
- The breakage of these studs occurred gradually.
- An abnormal accumulation of carbon was observed on the pistons and cylinders, which likely caused detonation and pre-ignition within the engine.