What happened
On 16 June 2006, a private pilot was conducting a proving flight in the Fish Eagle, registration ZU-BNH, traveling from Port Elizabeth toward East London. During the journey, the pilot opted to make an intermediate stop at Port Alfred Aerodrome. Upon preparing for departure, the pilot selected Runway 10R, choosing the grass surface because it appeared the smoothest among the available runways, despite it being slightly damp.
As the aircraft accelerated, the pilot noted that the airspeed was not increasing at the expected rate. In response to this lack of acceleration, the pilot attempted to abort the takeoff. However, the aircraft could not be brought to a halt before reaching the end of the runway. The aircraft exited the runway into an overrun area characterized by rough grass. During the excursion, the nose wheel assembly failed, and the right wing struck a small tree. The momentum of the rear-mounted engine then caused the aircraft to pitch forward and settle in an inverted position. Although the pilot was trapped in the cockpit, bystanders were able to upright the aircraft and assist in his release. There were 0 fatalities and 0 injuries reported.
The investigation
The investigation examined the operational conditions and the technical specifications of the ZU-BNH. It was noted that the aircraft was operating under a Proving Flight Authority, a status used to evaluate and test this specific type, which was the first of its kind on the South African register. At the time of the incident, the airframe had logged only 35.6 hours.
Investigators analyzed the aircraft's landing gear and the runway conditions. They determined that the undercarriage was not engineered for the stresses of rougher surfaces. The wheels, particularly the 10-inch nose wheel, were quite small, which effectively limited the aircraft's safe operation to hard surfaces such as asphalt or gravel.
Findings
- The pilot initiated a rejected takeoff after observing insufficient acceleration on a damp, grass runway.
- The aircraft failed to stop within the remaining runway length, leading to the excursion.
- The aircraft's undercarriage was not designed for operation on rough or unpaved surfaces, as the small wheel diameter restricted its use to hard runways.