On March 27, 1997, a Cessna 185 (registration N4855C) was involved in an aviation accident near Chugiak, AK. Investigators recorded the probable cause as: The pilot's improper installation of the main landing gear wheel penetration skis, which allowed the skis to rotate to a vertical position in flight and subsequently separate during landing. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot, also a licensed aviation mechanic, installed wheel penetration skis on his personal airplane. During a test flight, the skis rotated nose-up and remained vertical. On landing in snow, one ski broke off, causing the gear leg to penetrate the snow and the right wing and elevator to strike the surface.
Synopsis
A pilot who was also a licensed aviation mechanic installed wheel penetration skis on the main landing gear of his personal airplane. A subsequent test flight revealed a critical issue with the ski alignment.
Event Details
During the test flight, the skis immediately rotated nose-up to a near vertical position. The pilot continued around the traffic pattern and landed in snow just prior to the start of the runway. The skis failed to return from the near vertical position. During the landing roll, one ski broke off, allowing the gear leg to penetrate the snow. This caused the right wing and elevator to strike the snow surface.
Postaccident Examination
A postaccident examination of the skis disclosed that the ski check cables at the heel of the skis were excessively long. No other factors were identified in the report.