THE DTSB
The DTSB determines the Probable Cause of this accident to be Pilot Error, in that the pilot maneuvered the aircraft at such an altitude, speed, and bank angle which ultimately placed the aircraft in an area of mountain wave or extreme downdraft condition. This eventually led to an aerodynamic stall condition, due to the pilot attempting to reduce the rate of descent in the very last seconds before impact. The flight was operating at a high gross weight, with two pilots and a photographer on board, and maneuvering to capture images necessary for the American Red Cross relief efforts. It is suspected that the pilot became distracted in gusty, turbulent conditions and turned the aircraft to enter an area of rising terrain and downdraft on the downwind side of a sharp ridge, during a period of known high winds and turbulence. Of the three persons on board, one survived and provided this narrative: “The survivor thought that the pilot was returning to the FNL base. He stated that the airplane was maneuvering over trees, about 1,500 AGL, heading toward higher terrain (a ridgeline). Within seconds, he heard the pilot say “Oh [expletive].” The pilot lowered the nose and started to turn. He stated that the airplane seemed to drop, and that the airplane encountered a downdraft. He heard the airplane hitting trees, and the next thing that he remembered was being on the ground. It is not suspected that loss of thrust or power plant problems contributed to the descent into terrain.