What happened
On March 31, 2018, a Grumman G164, registration LV-CSU, was being repositioned from the Intendente Alvear aerodrome to a private hangar at the Azcarate Irastorzo aerodrome to protect it from deteriorating weather. During the flight, the pilot landed on runway 36. Approximately 450 meters after touchdown, the pilot lost directional control, causing the aircraft to veer right. The aircraft eventually exited the runway and struck a perimeter fence 15 meters from the edge of the pavement. The incident resulted in significant damage to the tail skid and the left wing, though there were no injuries to the crew.
The investigation
Investigators examined the aircraft and the airfield conditions following the event. The investigation revealed that the airfield's windsock was out of service for repairs at the time of the accident, depriving the pilot of a critical visual aid for assessing wind direction and intensity. Technical inspections of the aircraft's engine and flight controls showed no mechanical failures contributing to the excursion. However, the investigation uncovered severe regulatory and maintenance issues. The aircraft lacked a valid certificate of airworthiness, and there was no documentary evidence that required inspections had been performed. Furthermore, laboratory analysis of the fuel revealed that the aircraft was using commercial super gasoline contaminated with solids, such as fibers and silica, which is prohibited for use in aircraft engines by Argentine authorities.
Findings
- The primary cause of the excursion was a tailwind exceeding the operational limits established in the aircraft's flight manual, which compromised directional control during the landing roll.
- Adverse meteorological conditions, characterized by strong winds and gusts of up to 30 knots, contributed to the loss of control.
- The aircraft was not in an airworthy condition due to a lack of required maintenance inspections and the absence of a valid airworthiness certificate.
- The use of contaminated, non-aviation grade fuel was identified as a significant safety concern.