The pilot, with three passengers, proceeded toward the runway in Dallas, Texas, for departure, in a Cessna 421A.
As the twin-engine airplane approached the taxiway intersection, the right main landing gear collapsed, causing the right wing tank and right engine propeller to hit the ground.
Examination of the airplane revealed substantial damage to the right wing and damage to the right engine propeller.
Further examination of the landing gear revealed that the gear was not properly rigged.
The NTSB determined the probable cause as the improper rigging of the landing gear by maintenance personnel, which resulted in the landing gear collapse.
NTSB Identification: CEN14CA310
This May 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.
I worked for the big “C” in ICT for 14+ years and seen a myriad of used twins with the torque tube electric gear that were not maintained properly. 310’s thru 421’s. The lack of rigging tools and lack of lubrication on all of them causes rod end looseness and throws the rigging out the window. Part of the trouble lies with the lack of lubrication fittings to assure proper control of wear and friction in the system along with weakened springs due to age.
Some of the smaller feeder airlines used these craft for passenger service requiring them to service the gear weekly due to the activity of gear cycles, but they still wear out. A privately owned ship may not get the attention until an annual inspection is done if any.
NTSB data for years have shown about 20% of aircraft mishaps have a maintenance root cause. According to Mike Busch (see the EAA webinar recordings) half of those are the direct result of an A&P or Avionics tech error. In the bigger scheme of things, it’s a good thing for the gear to collapse enroute to takeoff, rather than during the touchdown or landing roll. Kudos to the AI/A&P for assuring and early (and relatively safe) failure. 🙂