Cessna 421 HB-LDV Landing Gear Accident at Zurich Airport

Flight Details and Incident Sequence On 11 April 1971, a Cessna 421, registration HB-LDV, departed Geneva Airport at 1235 local time for a non-scheduled commercial flight to Zurich. The flight was conducted under instrument flight rules. During the final approach, the landing gear was extended, and both occupants observed the three green gear lights indicating proper locking. The aircraft touched down on runway 16 at approximately 110 mph after a 600-meter approach. About 300 meters into the rollout, increasing shaking occurred, which the pilot initially attributed to a flat nose-wheel tire. While attempting to turn onto taxiway 2a, the vibration intensified until the aircraft became uncontrollable and the nose gear collapsed. The aircraft came to rest approximately 1,410 meters down the runway at 1323 local time. ## Damage and Investigation Findings Both occupants were uninjured, while the aircraft sustained heavy damage. The nose gear was found unlocked and bent, with the nose-wheel tube broken into fragments. The tire itself showed no significant damage. Inspectors determined that the damage to the nose-gear control and locking linkages resulted from forced fracture due to bending stress, with no evidence of pre-existing damage or material fatigue. ## Probable Cause The official report attributed the accident to the release of the nose-gear locking mechanism after landing as a result of excessive vibrations, likely caused by a pressure loss in the nose-wheel tube.