What happened
The pilot was operating a ski-equipped airplane with the intention of landing on a frozen, snow-covered lake to wait out deteriorating weather conditions. During the final approach and subsequent landing roll, the pilot reported failing to notice an area of drifted snow on the surface.
As the aircraft rolled along the ice, the left main landing gear ski made contact with the concealed snow drift. This interaction caused the airplane to yaw sharply to the left. The sudden directional change resulted in the nose of the aircraft striking the ground, leading to a nose-over incident. The event caused substantial damage to the airframe.
The investigation
The investigation focused on the physical evidence at the landing site and the pilot's account of the events. Investigators examined the condition of the frozen lake surface and identified the specific area where the snow drift was located. They confirmed that the left main landing gear ski had impacted the drifted snow, which initiated the loss of directional control.
Findings
The primary factor in this accident was the pilot's failure to see a visible obstacle during the landing roll. The presence of the drifted snow on the otherwise uniform surface created a hazardous condition that was not apparent until contact was made. This unexpected resistance caused the aircraft to turn and subsequently nose over.
Safety message
Pilots operating in winter environments should exercise extreme caution when landing on frozen bodies of water. Surface conditions can vary significantly, and obstacles such as snow drifts may be difficult to distinguish from the surrounding ice or snow. Thorough visual inspection prior to touchdown is essential to avoid similar incidents.