What happened
The accident occurred while the aircraft was taxiing on Runway 9, preparing for a takeoff on Runway 27. During this maneuver, the left main landing gear dropped off the edge of the runway and sank into soft terrain adjacent to the pavement.
In an effort to recover, the pilot attempted to steer the nose gear back onto the paved surface by turning the aircraft to gain better traction or leverage. This corrective action proved ineffective. Consequently, both the nose gear and the left main gear departed the runway entirely. The aircraft then nosed over, coming to rest on its back.
The investigation
Investigation of the site revealed that the airport was currently under construction and had not yet been completed. The unfinished state of the airfield contributed to the unstable terrain surrounding the active runway areas.