Operation Overview
At about 0900 hours on 24 July 2002, the pilot began spraying operations on flat farmland in the Orongo area, approximately three kilometres southwest of Thames Aerodrome. The pilot's father, an experienced agricultural pilot, supervised and loaded the aircraft. The pilot had recently qualified for spraying, with all previous agricultural experience being topdressing. Spraying was suspended at about 1210 hours due to unsuitable wind conditions, and both pilot and loader driver took a lunch break. Conditions improved, and spraying resumed at 1350 hours, completing the first property. The second property was started at 1420 hours.
Accident Sequence
The paddocks on the second property had long axes aligned approximately northwest-southeast. The pilot conducted spray runs at right angles to this alignment, progressively covering several paddocks on each run. A row of about 30 mature trees delineated the beginning of the runs, over which the pilot descended on a southwesterly heading. For a remaining paddock on the other side of the trees, with a barn and stockyards at its northwestern end, the pilot approached over the barn and made the first spray run to the southeast. He executed a 180-degree reversal turn and aligned the aircraft with the left boundary of the paddock in close proximity to the trees, flying into the sun toward the barn. Partway into this run, the left wing outer panel struck a protruding branch, tearing off part of the aileron. Further collisions occurred as the aircraft progressed along the tree line. The aircraft rolled inverted, struck the ground, and slid to a halt with the engine still running.
Aftermath
The farmer and his partner were driving separately along the nearby road toward the barn when the accident happened. The farmer continued to the scene while his partner alerted emergency services. Arriving at the aircraft, the farmer quickly realised there was nothing he could do for the pilot.
Investigation
The accident occurred in daylight at approximately 1450 hours NZST at an elevation of 10 feet. Official conclusions stated that the pilot was appropriately licensed, rated, and fit; the aircraft had been operating normally; and while flying into the sun and in close proximity to a line of trees, the left wing struck a substantial branch. The initial collision damaged the left aileron, and subsequent collisions progressively demolished the outer wing section. The aircraft damage resulted in a probably uncontrollable roll, followed by an inverted ground impact. The accident was not survivable, and the aircraft structure lacked rollover protection for the cockpit occupant.