Flight and Maneuvering
Four minutes after takeoff, the airplane was observed flying straight toward rising terrain. Other pilots reported that uplifting air movement had been present in the area during the previous several days. Radar data indicates that the airplane leveled off and began to slow down. It then changed direction and flew over the edge of a 1,000-foot canyon. The airplane subsequently turned north, again heading toward rising terrain.
Witness Observations
A witness reported that he could not hear any engine sound from the airplane. He observed the airplane spin toward the ground, then heard an impact sound and saw smoke.
Accident Site Examination
Examination of the accident site revealed that the airplane impacted the ground in a vertical attitude. The rear propeller was found feathered, and the front propeller showed no signatures of power. The rear engine fuel selector was positioned between main and off, while the front engine fuel selector was found set to auxiliary. Normal procedure is to fly for one hour after takeoff on the main tanks.
Pilot Reports and Recommendations
Pilots on later flights in the same area reported strong turbulence and very strong variable vertical air movements. The FAA recommends that a mountain ridgeline should be crossed at an angle to allow the pilot to turn away from the ridge with the least amount of turn required should down air be encountered.