What happened
On October 21, 2019, a Pipistrel Alpha Trainer, registration LV-S034, was performing a general aviation training flight from La Cumbre Aerodrome in Córdoba, Argentina. During the takeoff roll, after the aircraft had rotated, the crew experienced a sudden loss of control in flight. Due to the low altitude at the time of the event, the aircraft drifted to the left side of the runway within the aerodrome grounds.
As the aircraft moved across the terrain, the left wingtip and the left main landing gear made contact with the ground. The impact caused the main landing gear to collapse and resulted in the destruction of the propeller. The aircraft traveled approximately 150 meters before coming to a complete stop. There were no injuries to the pilot or the instructor on board.
The investigation
The investigation established that prior to rotation, the pilot had verified that all engine parameters and airspeed were within normal operating limits, cross-checking these values with the instructor. However, once the aircraft was fully airborne, a sudden lateral wind gust caused a rapid leftward roll that the crew could not counteract.
Investigators noted that while the initial meteorological conditions were favorable, the aerodrome's location in a mountainous region makes it prone to sudden, unpredictable wind gusts and frequent changes in wind direction. The investigation also examined the physical evidence on the runway, which showed three distinct marks corresponding to the wingtip and landing gear impact points.
Findings
- The primary cause of the accident was a loss of control in flight caused by a wind gust that likely exceeded the aircraft's maximum crosswind limitations.
- As the windward (right) wing lifted, the increased surface area exposed to the crosswind exacerbated the lateral movement.
- The lateral force exerted on the aircraft while on the ground caused severe side loading on the landing gear, leading to its structural failure.
- The aerodrome's mountainous environment contributes to the occurrence of sudden wind gusts without prior warning.