The airline transport pilot was conducting a personal cross-country flight in the experimental amateur-built, tailwheel-equipped Carbon Cub.
He reported that, while landing on a turf and gravel airstrip in Wasilla, Alaska, the airplane veered sharply left as the tailwheel touched down.
Despite applying full right rudder and brake controls, he was unable to correct the airplane’s track, and the right wing and horizontal stabilizer hit the ground.
After the airplane stopped, he was unable to straighten the tailwheel with the rudder control inputs because the tailwheel was bent.
Postaccident metallurgical examination of the tailwheel suspension system revealed fractures within the welds of the assembly and a fatigue fracture at the bolt hole for mounting the tailwheel.
The crack fracture surfaces exhibited orange and dark red corrosion, suggesting that the cracks were preexisting, and the fracture surfaces were consistent with overstress. The assembly also exhibited general twisting deformation, primarily as the result of deformation in the pivot bracket.
Probable cause: The failure of the tailwheel suspension assembly during landing due to preexisting fatigue fractures in the suspension system, which resulted in a loss of directional control.
NTSB Identification: ANC16LA059
This August 2016 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.
Rough operations required heavy scrutinizing of those highly loaded components during preflight and even post flight if a rental. Many ag pilots check the tail upon each flight of the day and lube those components extensively.