What happened
The pilot departed San Jose, California, for a cross-country flight to Sisters, Oregon. Prior to departure, the pilot obtained a standard preflight weather briefing which indicated that visual flight was not recommended due to reported cumulus buildups. The pilot intended to fly above the cloud tops and did not file a flight plan for the trip.
During the flight, the pilot maintained contact with his wife via cell phone while she drove to the same destination. After the aircraft failed to arrive at its destination, a search operation was initiated. Radar data indicated that the aircraft began a rapid descent from 15,400 feet, and radar contact was lost once the aircraft reached 11,800 feet. Witnesses observed the aircraft descending near vertically out of broken clouds with the engine operating at full power.
The investigation
Upon recovery of the wreckage, investigators noted that the right outboard wing panel, starting from approximately station 110 outboard, was missing. The outer wing panel was located about one month later. An analysis of the failed structure revealed a positive overload of both the wing and the horizontal stabilators.