The flight instructor of the tailwheel-equipped Piper J-3 Cub reported that the purpose of the flight was to demonstrate a short-field takeoff at the airport in Yakima, Washington, to a student.
During the takeoff roll, about rotation speed, the left wing unexpectedly dropped and hit the ground.
Subsequently, the plane ground looped and sustained substantial damage to both wings and the empennage.
The flight instructor reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.
Probable cause: The flight instructor’s failure to maintain directional control during the takeoff roll.
NTSB Identification: GAA18CA001
This October 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.