The commercial pilot was concluding a personal flight with two passengers on board the Cessna 421. He reported that, during the landing roll and after a normal touchdown on the concrete runway in Charleston, S.C., the right main landing gear collapsed. The plane then veered right and hit two runway lights, which resulted in substantial damage to the right wing rear spar.
Examination of the plane revealed that the right main landing gear down-lock bellcrank was fractured and had separated from its trunnion. The bellcrank bolt was sheared at the bolt head, consistent with overload.
The upper end of the bellcrank remained attached to the outboard push-pull tube. The lower end of the bellcrank, which attached to the rod end fitting at the lower side link, was broken, consistent with a ductile tension failure.
The fracture location was consistent with additional stress that would have been placed on the bellcrank if the landing gear was not properly rigged, however, damage to the landing gear precluded the ability to functionally check or verify whether the gear was properly rigged.
Review of maintenance records revealed that the airplane had been operated for about four hours since its most recent annual inspection, which was performed about two months before the accident. At that time, maintenance, including the adjustment of the right MLG travel, was performed on the airplane.
The NTSB determined the probable cause as inadequate maintenance, which resulted in the collapse of the right main landing gear during landing.
NTSB Identification: ERA14LA170
This March 2014 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.
The Cessna 300 and 400 series twin engine aircraft have maintainability issues. People don’t service the rod ends and the wear out. The rigging of these landing gear including the nose requires certain tools and a hunter spring gage to properly rig this system. READ the manual thoroughly before making adjustments and then conduct several retraction/extension checks before flying off into the wild blue yonder.