What happened
The pilot was operating a tailwheel-equipped airplane on a private airstrip, preparing for departure. While taxiing into position for takeoff, the aircraft's main landing gear encountered a ditch along the runway surface. The impact with the ditch halted the airplane's forward momentum almost immediately. Following this sudden stop, the aircraft nosed over and came to rest in an inverted position.
The investigation
After the incident, the pilot conducted a visual inspection of the airframe to assess the extent of the damage. The examination revealed that the rudder and two lift struts were bent due to the force of the accident. Despite the structural deformation, the pilot reported no mechanical anomalies or pre-existing issues with the aircraft prior to the taxiing phase.
Findings
The primary factor in this incident was the interaction between the main landing gear and a ditch on the private airstrip during the takeoff roll preparation. The abrupt stop caused by the gear striking the depression led directly to the nose-over event. No mechanical failure of the aircraft systems was identified as a contributing factor.