What happened
On February 22, 2018, an EMB 202 aircraft, registered as PT-UON, was performing agricultural spraying operations near Tangará da Serra, Mato Grosso. The aircraft, operated by Rondon Aviação Agrícola Ltda., departed from a landing strip at Fazenda Castro Alves to apply pesticides to pastureland. During its third application pass, the aircraft experienced an engine failure. The pilot was forced to perform an emergency landing in an open field ahead of the flight path. While the aircraft sustained substantial damage, the pilot emerged from the incident uninjured.
The investigation
CENIPA investigators confirmed that the pilot was fully qualified, holding valid commercial and agricultural licenses, as well as a valid medical certificate. The aircraft was also in compliance with all regulatory requirements, including a valid airworthiness certificate, up-to-date maintenance logs, and proper weight and balance.
Technical analysis of the engine, conducted by the Institute of Aeronautics and Space (IAE), identified that the mechanical fuel pump had failed due to the breakage of the diaphragm drive shaft caused by material fatigue. This specific failure mode was later addressed in an Embraer Service Bulletin (No. 200-028-0022), which recommended keeping the auxiliary electric pump running during all flight phases to prevent engine failure in the event of a mechanical pump malfunction.
Although the pilot stated that the electric pump was active during the flight, investigators conducted bench tests simulating the mechanical pump failure. The tests demonstrated that the electric pump was capable of maintaining sufficient fuel pressure to sustain engine operation without any drop in RPM. Consequently, the investigation concluded that the most likely cause was that the electric pump was not actually engaged, leading to fuel starvation.
Findings
- The mechanical fuel pump's drive shaft failed due to material fatigue.
- The electric fuel pump was likely not operational during the flight, preventing the engine from receiving adequate fuel after the mechanical pump failed.
- The pilot's decision-making regarding the use of the auxiliary pump remained an indeterminate contributing factor.