Aircraft and Operator
The accident involved a Hughes 269C helicopter, manufactured by Schweizer Aircraft Corporation, USA. The operator was a flight school. The helicopter was registered in Austria.
Event
On 11 December 2001 at approximately 13:25 UTC, a flight instructor and a student pilot were conducting a training flight on dual controls at Stockerau airfield, located in Lower Austria at an elevation of 209 meters above sea level. The accident occurred during the hover phase at 2-3 meters above ground.
According to the reconstruction based on statements from the occupants and investigation findings, the student pilot initiated a left rotation around the vertical axis by excessive deflection of the left tail rotor pedal. The main rotor of the helicopter rotates clockwise (viewed from above), so left pedal input increases pitch on the tail rotor to counteract main rotor torque and yaw the nose left. The student was unable to control the rotation. When the flight instructor attempted to intervene and stop the rotation by applying the right tail rotor pedal, the pedal broke at the cotter pin hole. The instructor then gave the command "My control," which was acknowledged by the student with "Your control." The instructor proceeded to land the helicopter. The helicopter struck the ground hard while still rotating left. The flight instructor reported no unusual resistance when depressing the right pedal.
Personnel Injuries
Both occupants were wearing seatbelts and were able to exit the helicopter unassisted. The flight instructor sustained minor injuries when striking his head against a metal fitting on the right door frame while exiting. The student pilot was not injured.
Aircraft Damage
The helicopter was destroyed.
Investigation
A simplified investigation was conducted under the Austrian Aircraft Accident Investigation Act (FlUG). The investigation did not determine a probable cause for the accident.