What happened
The aircraft experienced a structural failure during the landing roll-out phase. Specifically, the right main landing gear assembly collapsed in an outward direction upon contact with the runway surface.
The investigation
Following the incident, technical examiners conducted a detailed inspection of the landing gear components to determine the root cause of the collapse. The examination focused on the retention mechanisms for the torque links associated with both the left and right gear assemblies.
The inspection of the right gear assembly revealed that the bolt responsible for securing the upper and lower gear torque links was entirely missing. This absence compromised the structural integrity of the gear strut during the high-stress landing event.
Furthermore, a similar deficiency was identified in the left gear assembly. The required cotter pin, which is designed to secure the corresponding bolt for the left gear, was also found to be missing. While the left gear did not collapse during this specific incident, the lack of proper retention hardware posed a significant risk.
Findings
The investigation concluded that the collapse was directly related to the absence of critical fastening hardware. The missing bolt on the right side and the missing cotter pin on the left side indicated a failure in the maintenance or inspection process prior to flight.