Primary finding
Probable cause
Inadequate preflight/planning preparation. Factors to the accident were: downdraft and tailwind.
Investigator assessment
Analysis narrative
The aircraft was departing from an airport located in a mountainous area that is surrounded by trees and steeply sloping terrain. The preferred runway for departure, when wind conditions permit, is runway 04, which slopes downhill and has lower terrain off the end of the runway. The pilot took off on runway 04 with a tailwind. The airplane encountered a downdraft near the end of the runway and descended into trees. The pilot reported that there were no mechanical failures or malfunctions with the airplane at the time of the accident.
Source record
Factual narrative
On June 11, 1995, at 1130 mountain daylight time, a Cessna 175, N7142M, collided with trees shortly after takeoff from the Upper Loon Creek airstrip located 26 miles west of Challis, Idaho. Visual meteorological conditions prevailed at the time and no flight plan was filed. The airplane was substantially damaged and the private pilot and his passenger received minor injuries. During a telephone interview and subsequent written statement, the pilot reported that he was taking off from runway 4 with an approximate 10 knot tailwind. During the takeoff roll, on the gravel strip, the airplane lifted off and began to gain altitude. The pilot stated that at the end of the runway, the airplane encountered a severe down draft and descended into trees near the end of the runway. The pilot reported that there were no mechanical failures or malfunctions with the airplane at the time of the accident. The Idaho Airport Facilities Directory states under the remarks section: "Recommend land rwy 22, depart rwy 4 when wind conditions permit." The runway is surrounded by trees and steeply sloping mountainous terrain. -