Primary finding
Probable cause
corrosion in the left main landing gear cluster, which resulted in a failure of the left main landing gear. Inadequate inspection by undetermined maintenance personnel was a related factor.
Investigator assessment
Analysis narrative
The pilot stated that he was landing to the south with the wind from the west. The aircraft drifted to the right and went off the runway. Subsequently, the left wing was damaged, and damage was found at the left landing gear cluster on the fuselage. The pilot stated that he believed that the landing gear may have sustained damage during his last departure. The departure airstrip was rough with broken bunch grass. The pilot said everything appeared fine until the aircraft touched down at the destination, where it was uncontrollable and ground-looped to the right. Examination revealed that three of the support tubes on the left main landing gear cluster were corroded and had preexisting bending and failures, which were attributed to a landing gear failure. Reportedly, the area was accessible for inspection.
Source record
Factual narrative
On August 12, 1996, approximately 1945 mountain daylight time, a Piper PA-22-150 tailwheel-converted airplane, N7507D, sustained substantial damage when the pilot lost directional control in a crosswind during landing. The private pilot and his passenger were uninjured. No flight plan was filed for the flight, which had departed Magic Valley Reservoir, Idaho, about 1845. Visual meteorological conditions prevailed at the time of the accident. In a telephone interview, the pilot stated that he was landing to the south, with the winds from the west. The aircraft drifted to the right and left the runway, impacting the left wingtip and damaging the left landing gear cluster on the fuselage. In a written statement, the pilot stated that he believed that the landing gear may have sustained damage during his departure from Magic Valley Reservoir, as that airstrip was rough with broken bunch grass. He said everything was fine until he touched down at Challis and found the airplane uncontrollable. He said the airplane ground-looped to the right side of the runway, damaging the left wing, left main landing gear and the propeller and crankshaft. When the aircraft was inspected by a mechanic, the mechanic determined that three of the support tubes of the left main landing gear cluster were corroded and had preexisting failures, which he attributed to causing the landing gear collapse. The area of preexisting damage is accessible for inspection. -