NTSB Factual Report

The pilot stated that, when starting to takeoff in the tailwheel-equipped airplane he immediately applied full throttle and lost control of the airplane. The airplane departed the runway to the left and impacted a visual approach slope indicator control box, resulting in substantial damage to the right wing spar. The pilot reported that there were no mechanical malfunctions or anomalies with the airplane, and said that the accident may have been prevented if he had applied the throttle gradually.

NTSB Probable Cause

The pilot's failure to maintain directional control during takeoff due to his abrupt advancing of the throttle.