Incident Description
While on final approach, the pilot moved the landing gear lever to the extended position. The pilot heard the normal sounds of the gear extending and noted that the three green landing gear position lights were illuminated. However, upon looking at the nose landing gear through a mirror on the left engine cowling, the pilot observed that the nose gear was hanging at a 45-degree angle. The pilot attempted to cycle the gear, but the nose landing gear did not move. The pilot executed a go-around.
Subsequently, the pilot attempted to use the emergency gear extension procedure and contacted various maintenance facilities via aircraft radio. The pilot then performed a low fly-by of the air traffic control tower (ATCT). Controllers at the ATCT observed that the main landing gear appeared down and locked, but the nose landing gear remained hanging at a 45-degree angle.
During the ensuing landing, the nose gear collapsed, and the pilot brought the airplane to a stop on the runway.
Examination Findings
Examination revealed that the airplane's nose landing gear right drag brace (link assembly) had separated. The National Transportation Safety Board (NTSB) examined the fracture surfaces and observed a banding pattern on both surfaces, consistent with fatigue. Ratchet marks indicated that the fatigue initiated from machining marks located in the blend radius between the narrow edge of one of the idler link lugs and the adjacent surface of the link.