What happened
On May 16, 2006, at approximately 05:34 UTC, a Grumman G-164 A, registration CS-DCC, operated by AGROAR – Trabalhos Aéreos Lda., departed from Évora Municipal Aerodrome for an aerial spraying mission near Alcácer do Sal. About one minute after takeoff, while the pilot was adjusting power at an altitude of approximately 300 feet, the engine suddenly lost all power.
Unable to maintain flight, the pilot was forced to perform an emergency landing in an unprepared area consisting of a pine grove with dense low-lying vegetation. The aircraft struck several trees and came to rest in an inverted position. The pilot, who was the sole occupant, was able to exit the wreckage uninjured.
The investigation
The GPIAAF investigation focused on determining why the engine failed despite no detectable mechanical defects in the engine, magnetos, or ignition system. Investigators examined the engine, fuel system, and the condition of the fuel at the time of the accident.
Testing of the engine components, including the camshaft, magnetos, and carburetor, revealed that the mechanical systems were functioning correctly. However, investigators found that the aircraft had been refueled from drums the previous day, and water had been detected in those same drums. Furthermore, water was found in the fuel system of another aircraft from the same operator performing similar work. While the pilot had performed a fuel drain procedure, the investigation concluded that the amount of water accumulated via condensation in the tanks was not entirely removed.
Findings
- The engine suffered a total loss of power immediately following takeoff.
- Water contamination in the fuel was the primary cause of the engine failure.
- The fuel used for refueling from drums contained sufficient water to cause an engine stoppage.
- The pilot's fuel system draining procedure was insufficient to eliminate all accumulated water from the tanks.
- The aircraft sustained a total loss due to the impact and subsequent inversion.