What happened
On March 14, 2022, a PIPER BRAVE PA-36-375, registration CS-DBU, was performing an agricultural work training flight at Santarém Aerodrome (LPSR) in Portugal. During the landing phase on runway 23, the pilot, who was utilizing the flight to gain proficiency in the aircraft type, configured the plane with full flaps (30°). Upon touchdown, the pilot lost directional control, causing the aircraft to deviate toward the right edge of the runway. This deviation initiated a 180-degree ground loop to the left. The pilot escaped the aircraft without injury, but the aircraft sustained substantial damage, including a broken right wing and the shearing of the right main landing gear leg.
The investigation
The GPIAAF examined the mechanical and operational aspects of the incident. Investigators analyzed the fracture surface of the right main landing gear leg and found no evidence of pre-existing structural anomalies or fatigue. Instead, the fracture patterns were consistent with an overload failure caused by the intense physical dynamics of the ground loop and the subsequent immobilization of the aircraft. The investigation also reviewed the pilot's experience, noting 12 total flight hours and 71 landings in tailwheel-configuration aircraft, though only 1.5 hours and 8 landings had been completed in this specific model. Meteorological conditions at the time included a northwest wind of 9 knots with gusts up to 17 knots, and visibility of at least 10 km.
Findings
- The primary cause of the incident was a lack of sufficient flight experience in tailwheel aircraft, which led to deficient piloting techniques during the landing roll.
- The loss of directional control initiated a ground loop that generated enough lateral force to collapse the right landing gear.
- The aircraft's tailwheel configuration inherently possesses a tendency to "weathervane" into the wind due to the greater surface area behind the main gear acting as a pivot point.
- There were no medical factors or pre-existing mechanical defects that contributed to the event.