On December 31, 1982, a Piper PA-34-200T (registration N477BL) operated by Robert G. Milne,iii was involved in an aviation accident near Prescott, AZ. Investigators recorded the probable cause as: Material failure in the trunnion allowed the right main landing gear to rotate out and clockwise, leading to collapse. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During the landing roll, the right main landing gear collapsed. Investigation revealed a material failure in the trunnion caused the gear to rotate out and clockwise. A similar crack had been discovered on the left gear assembly 67 flight hours earlier.
Accident Overview
During the landing roll, the right main landing gear collapsed. The aircraft was on the ground at the time, and the gear failure occurred without prior indication.
Examination Findings
On-scene examination of the collapsed landing gear determined that the right main gear was in the down and locked position at the time of the event. However, a material failure in the trunnion allowed the gear to rotate outward and clockwise, leading to the collapse. The trunnion is a critical component that connects the landing gear strut to the aircraft structure.
Prior Inspection
Approximately 67 flight hours before the accident, a similarly located crack had been discovered on the left main landing gear assembly during an inspection. At that time, the right main gear assembly was also inspected, and no discrepancies were found. The crack on the left gear was present but did not result in a collapse during that inspection cycle.
Probable cause
Material failure in the trunnion allowed the right main landing gear to rotate out and clockwise, leading to collapse.