SEA95LA135

The pilot used flaps for the takeoff, contrary to the airplane owner's manual recommendations about use of flaps for takeoff at high altitude. The airport is located at an elevation of 6,403 feet above sea level. Witnesses observed the pilot beginning his takeoff roll from midfield at the airport. The witnesses stated that the airplane became airborne and remained in close proximity to the ground. About 900 feet beyond the end of the runway, the left wing of the airplane struck the ground and the airplane cartwheeled. The pilot reported no mechanical malfunctions, and he stated that the airplane was affected by windshear and downdrafts.

On July 2, 1995, about 1630 hours mountain daylight time, N4319Q, a Cessna 172L, was substantially damaged during takeoff from the Stanley Airport, Stanley, Idaho. The commercial pilot and his passenger were not injured. Visual meteorological conditions prevailed and no flight plan had been filed. The personal flight was destined for Boise and was conducted under 14 CFR 91.

According to an FAA inspector from Boise, Idaho, witnesses stated that the airplane began the takeoff roll near the midpoint of a 4,300-foot turf runway. The airport is located at an elevation of 6,403 feet above mean sea level, and the temperature was reported to be about 62 degrees F. During the takeoff roll, the airplane became airborne and remained in close proximity to the ground. About 900 feet beyond the end of the runway, the left wing of the airplane struck the ground and the airplane cartwheeled. The pilot reported that there were no mechanical malfunctions, and that he began to raise the flaps during the initial climb in an attempt to increase the airplane's climb rate. He also stated that he then "... hit a downdraft."

In a written statement, the pilot stated:

I was just beginning to raise some flaps when we hit some turbulence and a downdraft. I left the flaps alone and we began to fly normally for an instant when we encountered another downdraft or windshear. I had to push the nose toward the ground to avoid stalling. We were only a couple hundred feet high, hence no room to recover. I was forced to [flare] and land in the field below."

Density altitude, based upon barometric pressure, was in excess of 8,000 feet above mean sea level. The owner's manual for the Cessna 172L states:

... during a high altitude take-off in hot weather where climb would be marginal with 10 degrees flaps, it is recommended that the flaps not be used for take-off. Flap settings greater than 10 degrees are not recommended at any time for take-off.