Accident Overview
On June 23, 2011, about 1130 eastern daylight time, a Cessna 182F, registration N3152U, was substantially damaged after a landing-gear collapse during taxi at Warrenton Airpark (7VG0) in Warrenton, Virginia. The certificated airline transport pilot and four passengers were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local skydiving flight, conducted under 14 CFR Part 91.
Aircraft Information
The airplane was a four-seat, high-wing, fixed conventional gear model equipped with a Continental O-470 engine. An airworthiness certificate was issued in 1962. The most recent annual inspection was completed on November 26, 2010, at 2,679 total aircraft hours. At the time of the accident, the aircraft had accumulated approximately 2,724.6 total flight hours.
Pilot Information
The pilot held an airline transport pilot certificate for airplane multiengine land, a commercial pilot certificate for airplane single engine land, and certificates as a flight instructor, ground instructor, and flight engineer. His most recent first-class medical certificate application was dated January 28, 2011, but was denied. He reported 7,200 total hours of flight experience on that date.
Examination Findings
According to the pilot, as he taxied the airplane to the runway for takeoff, the left main landing gear collapsed, resulting in substantial damage. Examination revealed the left main landing gear had fractured and completely separated from the airplane approximately six inches outboard of its attachment point at the airframe.
A National Transportation Safety Board (NTSB) materials specialist examined the left main landing gear segments. The fracture surface on the separated leg was smeared during the accident sequence. The segment remaining attached to the airframe displayed a pristine fracture with features consistent with fatigue failure. A detailed examination at the NTSB Materials Laboratory confirmed the failure due to fatigue. Examination of the underside of the landing gear strut in an area directly adjacent to the fatigue zone revealed multiple corrosion pits.
Maintenance Records
The Cessna Maintenance Manual (Model 100 Series 1963-68) included criteria for visual inspection of main gear components every 100 hours. In July 2007, Section 5 of the manual was revised to include information concerning corrosion control on landing gear springs. The Cessna continued airworthiness program also included criteria to inspect the main landing gear spring outboard support for corrosion every 1,000 hours or 3 years.