Incident Overview
During a stabilized approach and landing touchdown, the right main landing gear of the aircraft failed. The airplane remained controllable by the pilots and came to a stop on the runway, resting on its right wing. The DFW Fire Department arrived at the accident site in 35 seconds. Following communication between the aircraft's Captain and the Fire Department's Incident Commander, it was decided that an emergency evacuation was not necessary.
Examination Findings
Examination revealed that the right main gear's outer cylinder had fractured, allowing the lower portion of the gear, including the wheel assembly, to separate from the airplane. Research, examination, and testing of the cylinder determined that a forging fold was introduced into the material during the first stage of the forging process. The first stage is a hand operation, and its quality is highly dependent on the person performing it.
Crack Development and Failure
Following the first landing, the forging fold became a surface-breaking crack due to the normal loads imposed during landing. Although growth of the fatigue crack was suppressed by crack blunting, high load landings resulted in continued growth of the fatigue crack. Subsequently, the landing gear failed when the crack reached a critical length.
Maintenance Records
Additionally, the aircraft's maintenance records were reviewed and no anomalies were found.