ERA15LA160

The pilot made a soft-field landing to a grass runway, and the initial touchdown was on the main wheels with the airplane in a nose-up attitude. As the airplane decelerated, the pilot lowered the nosewheel and felt a "significant" shimmy after it touched down. The pilot thought the shimmy damper had failed, so he applied back pressure on the control wheel to minimize weight on the nosewheel. As the airplane continued to decelerate, the pilot again lowered the nose, and a more substantial vibration occurred. He then raised the nosewheel as much as possible. Eventually, so much groundspeed had depleted that he could no longer hold the airplane's nosewheel off the ground. When the nosewheel touched down again, it separated from the airplane. Examination of the airplane revealed that a bolt and associated washer and nut that attached the upper torque assembly to the nosewheel steering arm assembly was missing, and it was not located. The pilot said that he saw the bolt during his preflight inspection. It could not be determined when the bolt separated from the nosewheel. According to the airplane manufacturer, without that bolt, the lower shock strut assembly of the nosewheel would freely caster in the shock strut tube assembly, which would result in a significant shimmy, and the nosewheel steering control would be significantly reduced or nonexistent. Without the torque assembly attached, the shimmy dampener would have limited-to-no effect. A review of the airplane maintenance logbooks revealed that no recent maintenance had been conducted on the nosewheel. The fracture surfaces of the broken nosewheel assembly were consistent with having failed due to overload forces during landing, and no preimpact anomalies were noted. It could not be determined how the bolt separated from the nosewheel steering arm assembly.

On March 15, 2015, at 1134 eastern daylight time, N8452X, a Cessna 172C, sustained substantial damage during landing roll-out at the Peach State Airport (GA2), Williamson, Georgia. The airline transport rated pilot sustained minor injuries and the passenger was not injured. The airplane was registered to and operated by the R A Marsh Flying Club, Williamson, Georgia. No flight plan was filed for the local flight that departed about 1020. Visual meteorological conditions prevailed for the personal flight conducted under 14 Code of Federal Regulations Part 91. In a written statement, the pilot stated that he was making his first landing in the airplane, which was a soft field landing to a grass runway. The initial touchdown was on the main wheels with a nose up attitude. As the airplane decelerated, the pilot lowered the nose wheel. He said that immediately after the nose wheel touched down a "significant" nose shimmy was felt. The pilot thought the shimmy damper had failed, so he applied back pressure on the control wheel to minimize weight on the nose wheel. As the airplane continued to decelerate, the pilot again lowered the nose and a more substantial vibration occurred and he again raised the nose wheel as much as possible. Eventually, so much groundspeed had depleted that he could no longer hold the nose off the ground. When the nose wheel touched down on the ground for the last time, it completely failed and separated. The nose of the airplane then dropped to the ground and the airplane slid to a stop. A postaccident examination of the airplane was conducted by several Federal Aviation Administration (FAA) safety inspectors. According to one of the inspectors, the nose gear separated from the airplane and was fractured in several pieces. The firewall was wrinkled and the propeller was damaged. Examination of the nose gear revealed that an AN4-31 bolt and associated washer and nut that attached the upper torque assembly to the nose gear steering arm assembly was missing. The pilot said that he saw the bolt during his preflight inspection. The inspectors walked the grass runway in search of the bolt to see if it came out during takeoff or landing, but the bolt was not located. A review of photographs of the broken nose gear's fractured surfaces revealed the nose gear appeared to have separated from overload forces. According to a representative of the aircraft manufacturer, without this AN4-31 bolt, the lower shock assembly of the nose gear would freely caster in the shock strut tube assembly, which would result in a significant shimmy. In addition, nose-wheel steering control would also be significantly reduced or nonexistent. Without the torque assembly, the shimmy dampener would also have limited to no effect. A review of the aircraft maintenance logbooks revealed no recent work had been done to the nose gear. The pilot held a commercial pilot certificate for airplane single-engine land and an airline transport pilot rating formulti-engine land, and instrument airplane. The pilot reported a total of 17,065 total flight hours; of which, 3,000 of those hours were in a Cessna 172. He reported the weather at the time of the accident as calm wind and clear skies.