What happened
On 25 March 2005, a Cubby aircraft, registration ZU-DHN, was performing circuit training exercises at Bapsfontein Aerodrome. The flight was a private operation involving a pilot and one passenger. During the takeoff roll on Runway 02, the pilot applied power and began accelerating. As the aircraft reached the point of rotation, the pilot attempted to apply rudder corrections to compensate for engine torque and gyroscopic effects.
During this maneuver, the aircraft suddenly lost directional control. The aircraft veered toward the left side of the runway, leaving the paved surface and entering a ditch. The impact with the terrain caused the undercarriage to collapse and the propeller to strike the ground. Despite the significant impact, there were no injuries to the pilot or the passenger.
The investigation
Investigators examined the wreckage and the aircraft's maintenance history. The aircraft had undergone its last annual inspection in December 2004, with only 10.9 airframe hours logged since that certification. At the time of the incident, the aircraft was operating under a Proving Flight Authority.
Following the accident, the aircraft was recovered and inspected by the manufacturer. This technical examination focused on the flight control systems to determine why the aircraft failed to respond to pilot inputs during the takeoff roll.
Findings
- The primary cause of the excursion was the dislodgement of the left rudder pedal control cable swaging (crimped end) from its attachment lug.
- This mechanical failure resulted in a total loss of rudder authority during the critical takeoff phase.
- The loss of control caused the aircraft to deviate from the runway centerline, leading to the ditching and subsequent structural damage to the propeller and landing gear.