Aviat A-1C-180 N63WY accident near Kooskia, Idaho

Probable cause

The pilot's decision to attempt a takeoff with a gusty tailwind, which resulted in his loss of airplane control during the initial climb and an aerodynamic stall/spin.

NTSB analysis

The passenger reported that the pilot wanted "to beat" an approaching storm and that immediately after taking off and during the initial climb, the airplane rolled violently to the right; it then rolled back to the left, and the nose dropped before impact with terrain. A witness reported observing two men rushing to pack up their airplane while the weather at the airfield was deteriorating due to an incoming thunderstorm. He reported seeing the airplane make an uphill intersection takeoff with a strong gusting tailwind. The witness added that the airplane appeared unstable during the takeoff. A second witness reported that a thunderstorm was within one mile of the airfield and that the windsock was fully erect and moving around erratically, adding that the wind "was knocking the aircraft all over." The passenger stated that he thought the airplane was about tree top level when it encountered the violent wind condition and that the engine was running normally before the accident.

A postaccident examination of the airframe and engine revealed no mechanical malfunctions or failures that would have precluded normal operation. The pilot's decision to attempt a downwind takeoff in gusting wind conditions, coupled with a thunderstorm in close proximity to the airfield, most likely resulted in his loss of airplane control and subsequent impact with terrain.

Text from the NTSB. Open the NTSB docket for WPR12FA280 for the full record.