Incident Overview
The pilot reported that the approach and landing were normal, with the right main gear touching first due to a slight crosswind. Immediately after touchdown, the left main gear failed, causing the aircraft to depart the side of the runway.
Examination of the Failed Gear
Inspection of the left main gear found that the upper half of the scissor assembly had separated. This separation allowed the oleo piston and attached wheel assembly to detach from the remainder of the gear. Further examination of the broken scissor assembly revealed a small fatigue crack in the separated area. However, the ultimate failure was determined to be the result of a large overload condition that had been applied to the part on some previous occasion.
Conclusion
The incident was attributed to the left main gear's structural failure, initiated by a fatigue crack but ultimately caused by a prior overload event that compromised the scissor assembly's integrity.