What happened
On October 4, 2003, at approximately 16:30 local time, an EMB-202 aircraft, registration PT-UKD, operated by AGRIFOR Aviação Agrícola Formehl Ltda, crashed near Aripuanã, Mato Grosso. The aircraft had departed from Fazenda Cotriguaçu (SWQT) for a seed application mission approximately 4 NM from the airfield. Shortly after takeoff, the engine suffered a significant loss of power. In an attempt to manage the emergency, the pilot jettisoned the aircraft's load while simultaneously executing a left-hand turn. This maneuver caused the aircraft to enter an inadvertent stall, leading to a loss of control and a high-impact collision with the ground. The aircraft caught fire upon impact, and the pilot sustained fatal injuries.
The investigation
CENIPA investigators established that the engine failure was directly linked to the use of unauthorized fuel. Laboratory analysis of the remaining fuel revealed a mixture consisting of 85% ethyl alcohol and 15% hydrocarbons. The aircraft was certified to operate only on aviation gasoline. The investigation also noted that the fuel filler cap for the right wing was missing, and investigators suspected an intentional attempt to hide evidence of the irregular fuel use.
Regarding the human factors, the pilot was a relatively inexperienced professional who had recently completed agricultural flight training but had not yet received his formal agricultural pilot rating. The investigation found that the operator, AGRIFOR, had a history of non-compliance, having previously been cited for using unauthorized fuel in another aircraft. Furthermore, the pilot's decision to operate under these irregular conditions was attributed to personal financial pressures related to the costs of his flight training.
Findings
- The primary cause of the engine failure was the use of unauthorized ethanol-based fuel instead of approved aviation gasoline.
- The pilot's lack of experience in agricultural operations contributed to an improper response to the engine failure, specifically failing to prioritize aircraft control over secondary procedures like load jettisoning.
- The operator failed to provide adequate supervision, allowing the continued use of non-homologated fuel to reduce operational costs.
- The pilot demonstrated a complacent attitude toward safety regulations, influenced by personal financial obligations.
- The aircraft's load jettisoning created a pitch-up moment that, combined with the pilot's maneuvering, induced an aerodynamic stall.