The pilot reported that, while participating in a slow flight competition in Talkeetna, Alaska, he was over the target area for the radar speed check about 30′ above the ground, at 17 mph ground speed, when the left wing stalled.
He did not have sufficient altitude to recover, so the Backcountry Super Cub hit the ground. The airplane sustained substantial damage to both wings.
The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.
Probable cause: The pilot’s failure to maintain a proper airspeed and his exceedance of the airplane’s critical angle of attack, which resulted in an aerodynamic stall.
NTSB Identification: GAA17CA299
This May 2017 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.