What happened
During the landing phase of flight, the pilot reported that the aircraft floated excessively while in the flare. To correct the altitude, the pilot lowered the nose slightly, which resulted in the nose landing gear making initial contact with the runway surface. This premature and hard contact caused the aircraft to begin porpoising, a oscillating motion where the nose gear repeatedly struck the pavement with each cycle. On the third instance of this porpoising action, the structural integrity of the nose landing gear failed, causing it to collapse. Following the collapse, the aircraft slid along the runway until it came to a complete stop.
The investigation
The factual narrative provided by the pilot indicates that the sequence of events was initiated by an excessive float during the flare. The subsequent lowering of the nose led to premature gear contact. The repeated impact forces associated with the porpoising motion were sufficient to cause structural failure of the nose landing gear assembly on the third cycle.
Findings
The primary factor in this incident was the nose landing gear collapse resulting from the repetitive stress of porpoising. This condition was directly linked to the aircraft floating during the landing flare and the pilot's subsequent action of lowering the nose, which caused premature gear contact with the runway.