What happened
The pilot reported that during the takeoff roll from a grass runway, the aircraft encountered an unexpected surface irregularity. At approximately 40 miles per hour, the airplane was pulled sharply to the left after hitting a soft spot in the turf. This sudden deviation caused the aircraft to ground loop to the left.
As a result of the uncontrolled turn, the left landing gear collapsed under the stress. The impact also bent the left wing and damaged the fuselage. The pilot did not provide further details regarding the severity of injuries or specific weather conditions at the time of the incident.
The investigation
Examination of the aircraft revealed significant damage to the left side structure. The left landing gear assembly failed, leading to the collapse of that side of the undercarriage. The left wing sustained bending damage consistent with the ground loop dynamics described by the pilot. The fuselage also showed signs of damage resulting from the incident.
Findings
The primary factor in this accident was the interaction between the aircraft and the runway surface conditions. The soft spot on the grass runway created an asymmetric resistance during the high-speed takeoff roll. This caused the pilot to lose directional control, leading to the ground loop and subsequent structural failure of the left landing gear and wing.