What happened
A non-instrument rated pilot and two passengers departed Arlington, Washington, in a Cessna 180F intended for a flight across the Cascade Mountains to Spokane, Washington. No flight plan had been filed for the trip. At the time of departure, weather conditions at the airport consisted of a 2,000-foot broken ceiling with lowering ceilings further to the east.
Radar data tracked the aircraft moving east-southeast. The last radar target was recorded at 1410:01, at an estimated elevation of 5,200 feet, approximately 10 nautical miles east-southeast of the accident site. The aircraft eventually impacted trees and terrain with a +35 degree upslope at an elevation of approximately 3,850 feet MSL. The impact occurred while the aircraft was in a wings level attitude.
A witness located about one nautical mile north-northeast of the crash site reported hearing an aircraft approaching from the northwest and circling back toward the southwest. This was followed by a noise described as a "backfire" or "rifle-shot," after which there was silence. The witness also noted poor visibility due to overcast, foggy conditions, with heavy clouds and fog present at elevations between 2,400 and 3,500 feet.