THE DTSB
The DTSB determines the Probable Cause of this accident to be Pilot Error, in that the non instrument rated private pilot continued VFR flight into IMC conditions, and flew into an area of high terrain combined with low ceilings and visibilities, eventually impacting sharply rising terrain. The pilot was known to normally avoid night flight, and so embarked on a return trip from Yakima (KYKM) back to her residence airpark in Lake Chelan at around 3:40 pm local time, for a straight line distance of 84 nm. The crash occurred at about 4:00 pm local time, and was located 30 nm northeast of Yakima just north of interstate 90, Since the crash site is located well east of the straight line intended course, it is believed that the pilot turned more easterly after crossing interstate 90 due to low ceilings and visibility, and likely followed a lower elevation ravine trough aligned with her desired heading, hoping to reach lower terrain and better weather once north of the higher terrain. The pilot was well aware of R-6714F and R-6714G and made comment to others about wanting to remain well west of that restricted airspace. The pilot was a retired female pediatric nurse and was most concerned about being able to care for her two cats that were at her residence and needing attention. The pilot had a vehicle located at S10, just south of her residence airpark and she commented that she needed to leave early enough to land at S10 and drive the extra 45 minutes if weather was not good in that area as well, so the discussion of weather and contingencies did occur. The crash site was not located until the next morning due to lingering poor visibility in the area that night. The Cessna wreckage path indicates a high speed descending turn, and not an off field emergency landing.