Incident Overview
A flight instructor and a pilot-rated student were conducting proficiency training in off-airport landings and takeoffs using a tailwheel-equipped airplane. Following a landing on a gravel bar, both occupants exited the aircraft and inspected the takeoff area on foot to assess surface conditions.
Takeoff and Abort
During the subsequent takeoff run, the airplane did not achieve the expected acceleration. As the aircraft approached the predetermined abort point, the flight instructor instructed the student to discontinue the takeoff. The instructor then assisted by simultaneously handling the controls with the student.
Braking and Nose-Over
In the attempt to bring the airplane to a stop, the brakes were applied with excessive force. This action caused the aircraft to pitch forward and nose over onto its back.
Damage
The accident resulted in substantial damage to the rudder and vertical stabilizer. No occupant injuries were reported.
Findings
The source does not provide a stated probable cause for the accident.