Cessna 210 N222AT accident near San Bernardino, California

Probable cause

The fatigue failure of the left main landing gear (MLG) saddle, which resulted in the pilot's inability to extend the left MLG. Contributing to the accident was the pilot's improper decision to fly the airplane before the annual inspection was completed and the airplane returned to service in an airworthy condition.

NTSB analysis

The airplane was at a maintenance facility for an annual inspection, which had not been completed, and the airplane had not been returned to an airworthy condition. Despite this, the private pilot picked up his airplane from the maintenance facility to fly it to his base airport. While in the traffic pattern, the pilot lowered the main landing gear (MLG) but noted that the left MLG was not fully extended. The pilot attempted to manually extend the MLG to no avail and subsequently landed the airplane with the left MLG retracted.

Postaccident examination of the left MLG revealed that the saddle assembly had fractured. The assembly was removed for metallurgical examination, which revealed that the saddle fracture surfaces exhibited features consistent with fatigue.

An airworthiness directive (AD) required that the MLG saddles be inspected for cracks using the dye-penetrant procedure as part of the annual inspection. The mechanic who was conducting the annual inspection reported that he had not inspected the landing gear before the pilot took the airplane and that he had informed the pilot that the annual inspection was not complete and that he was not signing the airplane off as airworthy. It is likely that, if the AD had been complied with and the pilot had not taken the airplane before the annual inspection was complete, the preexisting crack would likely have been identified during the inspection of the MLG saddles.

Text from the NTSB. Open the NTSB docket for WPR18LA058 for the full record.