Accident Overview
During the landing roll, the nose landing gear collapsed, causing the airplane to depart the left side of the runway. The nose landing gear assembly was secured by four bolts. Post-accident examination revealed that two of these bolts were missing, and rust was present in the slots where the bolts had originally been installed.
Examination of Recovered Components
The pilot was able to recover one of the missing bolts. Inspection of this bolt showed evidence of shearing, which was consistent with a secondary failure mode. The second missing bolt was never located.
Maintenance History
The pilot stated that, to the best of his knowledge, the four bolts had never been replaced prior to the accident.
Condition of the Bolt Holes
Rust was observed in the bolt slots, indicating long-term exposure to moisture or lack of maintenance. The absence of two bolts and the failure of a third resulted in inadequate retention of the nose landing gear strut.