Aeronca 7DC N83391 accident near Nome Creek, Alaska

Probable cause

The failure of the airplane's structural tubing due to corrosion, which resulted in a tailwheel separation and a subsequent loss of control. Also causal was the mechanic's failure to perform a detailed inspection of the aft fuselage during the most recent annual inspection.

NTSB analysis

During landing on an unimproved runway, after the tailwheel contacted the ground, it’s mount failed, the rudder pedal jammed, and the airplane veered right. The pilot attempted to raise the tail to regain control with no effect. The airplane subsequently exited the intended landing area and came to rest in brush. A postaccident examination of the airplane revealed that the aft airframe tubing where the tailwheel was mounted to the airframe was corroded and fatigued, with cracks and discoloration from corrosion on the airframe.

The airplane had flown 44.9 hours and 109 days had elapsed since its most recent annual inspection. Review of maintenance records revealed no discrepancies related to the area of the tailwheel mount. It is likely that the mechanic failed to conduct a detailed inspection in the aft fuselage area, which would have identified the corrosion.

Text from the NTSB. Open the NTSB docket for ANC19LA024 for the full record.