Incident Details
The airplane was being operated as an instructional aircraft when, during landing, the nose landing gear collapsed. According to the flight instructor, neither he nor the dual student received a green indication that the gear was down and locked. The crew reported cycling the landing gear multiple times, but they were unable to obtain a down-and-locked indication.
Inspection Findings
Following the accident, an examination of the landing gear revealed that two nose gear down lock actuator pins had fractured due to fatigue. The fatigue cracks covered more than 70 percent of the fracture surface on each pin. The pins were of an older design. They had reportedly been inspected, and no looseness was observed prior to the flight.
Service Bulletin
Cessna service bulletin SEB95-20 recommends a recurring 200-hour inspection of the down lock pins for looseness. If any looseness or movement is found, service kit SK210-155 is to be installed before further flight. However, the bulletin does not require visual inspection of the pins for fatigue cracks. After the accident, the operator reported that one of the fractured pins was not felt to be loose until a greater amount of force was applied during a check for looseness.