ERA09LA467

The pilot reported that the approach was “on speed,” but upon initial touchdown the airplane bounced. The airplane then landed “firm” and immediately veered off the runway surface. Structural damage to the fuselage resulted. An inspector from the Federal Aviation Administration (FAA) reported that a section of the right main landing gear structure had failed. Postaccident examination of the fracture surface, which was adjacent to a weld line, revealed evidence of a preexisting crack. There was differential rusting on the crack surface indicative of progressive crack extension. The airplane had recently undergone an annual inspection, however the FAA inspector reported that the fracture surface could not be seen without disassembly of the landing gear.

On August 17, 2009, about 1330 eastern daylight time, a Cessna 140A, N9467A, was substantially damaged during landing at Westchester County Airport (HPN), White Plains, New York. The airplane was operated by a private individual. The commercial pilot was not injured. Visual meteorological conditions prevailed at the time, and no flight plan was filed for the 14 Code of Federal Regulations Part 91 personal flight. The flight originated at East Hampton, New York at 1300. The pilot reported that his approach to runway 34 was stable and on speed. As he began to flare, he sensed that he was slightly high, so he added power, leveled the nose, and flared again. The airplane touched down initially, bounced, and touched down again. The pilot described the landing as "firm." The airplane then "veered uncontrollably off to the left side of the runway." After exiting the airplane, the pilot noted that the right, main landing gear was separated from its gear box. An inspector from the Federal Aviation Administration (FAA) inspected the airplane following the accident. He reported that the right side "bulkhead assembly – landing gear failed. Specifically, the structure immediately under the gear that sandwiches the gear in place failed." The inspector reported that the airplane had recently undergone an annual inspection and the section where the part failed would not be visible without disassembly. The failed landing gear component, which was a welded “C” channel structure, was forwarded to the NTSB Materials Laboratory for inspection. The part had fractures at opposite ends. The fracture at one end of the structure was typical of shearing and tensile overstress separation. The fracture at the other end was adjacent to a weld line. For the majority of this fracture, the features were consistent with an overstress separation. However, a rusted and discolored region at the center leg of the “C” channel was indicative of a preexisting crack. Fracture face recontact damage and differential rusting of the fracture in this region was suggestive of progressive crack extension. The 1356 weather observation for HPN included the following: few clouds at 6,000 feet, surface winds variable at 4 knots, 8 statute miles visibility, temperature 31 degrees Celsius, dew point 19 degrees Celsius, and an altimeter setting of 30.16 inches of mercury.