Accident Details
On October 24, 2015, about 1500 Pacific daylight time, a tailwheel-equipped Cessna 120, registration N3124N, sustained substantial damage after nosing over during takeoff at Lone Pine Airport, Lone Pine, California. The private pilot, who was the sole occupant, was not injured. The flight was conducted as a personal cross-country trip under 14 Code of Federal Regulations Part 91, with a destination of Tehachapi, California. Visual meteorological conditions prevailed, and no flight plan was filed.
Pilot Account
During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge, the pilot reported that he was returning home from a weekend trip. During the takeoff roll on the dirt runway, after raising the tail, he felt the left main landing gear encounter soft soil. He attempted to correct, but the left main wheel continued to drag, and the airplane suddenly nosed over. The nose over resulted in substantial damage to the wings and empennage.
Postaccident Examination
Postaccident examination of the airplane revealed a fractured left main landing gear wheel axle. The NTSB Materials Laboratory conducted a detailed examination of the fracture surface. The analysis showed a fatigue fracture that originated from the outer surface of a circumferential weld between the lateral tube portion and the vertical plate portion of the axle. The fatigue crack origin areas were covered with yellow deposits, which energy-dispersive X-ray spectroscopy (EDS) identified as zinc chromate, a compound found in primer paint.