Incident Overview
During a cross-country flight, air traffic control informed the pilot that adverse weather, including terrain obscurement in clouds, precipitation, fog, or mist, was along the planned route. Turbulence was reported below 12,000 feet, and occasional moderate rime or mixed icing was forecast from the freezing level to 14,000 feet.
Pilot Communications
Further along the route, the pilot reported to a controller that he was at 13,000 feet and descending. The controller inquired whether the pilot was aware of the center weather advisory and reports of severe rime ice in the direction he was heading. The pilot acknowledged the advisory and stated that the aircraft was "equipped." The controller continued to relay pilot reports from commercial aircraft flight crews regarding icing conditions, but the pilot maintained his routing and again affirmed that the aircraft was "equipped."
During the last transmissions, the pilot reported that he was "turning on (de-ice) equipment now." The controller recommended that the pilot stay clear of the clouds, to which the pilot responded "roger." The controller then asked if the pilot was "going to orbit there for awhile," and the pilot replied "yes," followed by a partially unintelligible transmission: "getting some weather here." The pilot's final communications were "Ah, I'm in a little trouble," and then "Ah, standby 9KM."
Radar and Accident Details
Radar tracking indicated that the aircraft had been cruising at 16,500 feet before beginning a gradual descent. It descended to 12,700 feet and initiated a right turn. During this turn, the aircraft's altitude changed rapidly: first an increase, then a rapid loss of altitude—from 8,000 feet per minute to 10,600 feet per minute—before radar contact was lost.
The aircraft was found six months later in an area of mountainous terrain. On-site evidence showed that the aircraft collided with trees and terrain in a nose-low attitude, with the majority of the wreckage contained in a large deep crater.
Probable Cause
The official probable cause is: "The pilot's failure to maintain aircraft control while maneuvering. Icing conditions, clouds and the pilot's continued flight into known adverse weather were factors."