After a cross-country flight and during the landing roll at the airport in McKinney, Texas, the Cessna 340’s left main landing gear collapsed, causing substantial damage to the aileron.
An examination of the landing gear found the bell crank pivot bolt and gear down-lock broken.
A review of the airplane’s maintenance manual revealed that the landing gear system is to be disassembled/inspected every 10 years/5,000 landings, after an initial inspection after 20 years or 10,000 landings.
Additionally, the maintenance manual indicates that the main landing gear bell crank pivot bolt is to be inspected for wear every three years (or 500 landings), after an initial inspection at three years or 1,000 landings.
A review of the airplane maintenance records did not reveal an entry where the landing gear inspections had been accomplished. The records revealed the airframe had accumulated 5,799.3 hours at the time of the last annual inspection, which was dated September 1, 2016.
It’s likely that the landing gear pivot bolt developed a crack over time, which then failed during landing, causing the gear to collapse.
Probable cause: The failure of the bell crank pivot bolt, which resulted in the left main landing gear collapse. Contributing to the accident was the lack of landing gear inspections in accordance with the airplane manufacturer’s maintenance manuals.
NTSB Identification: CEN17LA351
This September 2017 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.