NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
During the landing approach, the flight instructor and pilot undergoing instruction were unable to fully extend or retract the left main landing gear and, after multiple unsuccessful troubleshooting attempts, performed a gear-up landing. Postaccident examination revealed that the pivot assembly for the left main landing gear actuator had fractured and had separation features consistent with torsional fatigue. The Federal Aviation Administration previously issued an airworthiness directive (AD), which included an inspection of pivot assemblies for cracks, in accordance with a manufacturer’s service bulletin (SB). The AD called for repetitive inspections of the pivot assembly if the airplane experienced a hard landing, and the SB recommended, in small print, full recompliance after a hard landing. The SB was complied with 12 years and 2,730 flight hours before the accident. The airplane was subsequently involved in a hard landing, and a reinspection was conducted; however, recompliance with the entire SB was not achieved as recommended in the SB, and the pivot failed 894 flight hours after the hard landing.