Flight Planning and Weather Briefings
The pilot, holding a Canadian Airline Transport Pilot (ATP) rating and reported to have over 30,000 hours of flight experience, planned a flight from Seattle, Washington, to Calgary, Alberta, in a Cessna U206G. On the day of the accident, he obtained three weather briefings from Seattle Flight Service between 0823 and 1040. A VFR flight north to Vancouver, British Columbia, and east across the Cascade Mountains was not recommended. Instead, the pilot chose a southerly route: south from Renton, Washington, to the Columbia River, east along the river to The Dalles, Oregon, then northeast to Spokane, Washington, where he planned to stop en route to Calgary.
The pre-departure weather briefing, as well as an in-flight briefing the pilot subsequently received, were found to be correct and satisfactory. Although the pilot was IFR rated, he did not file an IFR flight plan.
Route and Transponder Issues
The pilot filed his flight plan indicating the aircraft was equipped with a transponder Mode C. However, while approaching Spokane, he advised the tower that "...we're having some transponder trouble here...." The pilot's son later reported that the aircraft's transponder was questionable. Due to the lack of a transponder signal, radar vectors could not be utilized. The pilot subsequently radioed that he intended to "...see if I can work my way over to Coeur d'Alene or go back south and pick up a small airport...."
Witness Observations and Accident Location
A witness driving on highway 27 (at an elevation of 2,600 feet MSL) observed the aircraft heading north-northeast at approximately 300 feet AGL. The witness reported that the aircraft was under the fog line before disappearing into the fog heading toward Mica Peak. The aircraft then impacted trees on a heading of approximately 015 degrees and in a slightly nose-up attitude, subsequently impacting the rising terrain near Mica Peak at an elevation of 4,760 feet MSL. The witness described the weather conditions at his location as poor visibility, strong rain, low clouds, and fog.