Accident Sequence
On Friday, 31 March 2006, a topdressing pilot began operations at approximately 0600 hours, meeting a loader-driver at Kaitaia aerodrome. They flew to a farm airstrip near the Pukepoto Quarry, where a fertiliser-loading truck had been parked overnight. The morning was spent spreading about 25 tonnes of superphosphate on nearby farmland. When the superphosphate was nearly exhausted, a consignment of fresh lime was delivered. The operation continued with spreading lime on a property near the base of a hill range about three kilometres from the airstrip.
At around 1000 hours, while waiting for another lime delivery, the pilot and loader-driver flew to an airstrip near Broadwood, 20 km to the south-east, to reposition a fertiliser truck to another airstrip near Pawarenga for the next day's work. They returned to the original airstrip at about 1100 hours. The pilot then received a cell phone call from his supervising Chief Pilot. During the conversation, the pilot asked for advice on the best direction for spreading lime and commented that the lime was 'hanging up' and not flowing easily from the hopper. The Chief Pilot cautioned about poor flow properties of new lime and advised spreading in line with the hill range, not up the slope.
The operation resumed until the lime bin was empty. After a lunch break, during which the aircraft was refuelled and another truckload of lime arrived, the pilot mentioned to the loader-driver that the lime was still hanging up, requiring about two passes to clear the hopper. Just before the afternoon flights, the pilot had a cell phone conversation with a bank manager about his business finances. The loader-driver reported the pilot became agitated but appeared to calm down before flying.
A farm-owner observed the aircraft on its first afternoon flight as it completed two passes. After these, the aircraft flew further away, assumedly returning for another load. Other witnesses saw the aircraft flying parallel to a plantation of 30–40 metre high trees towards the rising hill range. The closest witness saw what appeared to be fertiliser dropping from the aircraft as it flew along the tree line up the slope. The dropping stopped, and the aircraft entered a steep right-hand turn away from the slope while descending. The aircraft disappeared into tall bush on the hillside, and witnesses heard impact. A large smoke-like cloud rose through the bush.
Upon hearing the impact, the farm-owner and a local share-milker searched for the aircraft, which was initially obscured by bush. The share-milker reached the wreckage and found the pilot deceased. The farm-owner alerted emergency services, but another property owner had already called the New Zealand Police. The accident occurred in daylight at approximately 1345 hours NZDT, 9 km south-west of Kaitaia at an elevation of 880 feet AMSL (coordinates: S 35° 10' 26.1", E 173° 11' 29.4").
Probable Cause
The investigation concluded that the probable initiator of the accident was a hung load of lime, which limited the aircraft's climb performance. Contributing factors included steep rising terrain and a high tree line that restricted turning options. The pilot's limited agricultural flying experience may have prevented him from recognising the predicament in time to take recovery action. The aircraft appeared to have aerodynamically stalled during a right-hand turn from which there was insufficient height to recover. Additionally, the pilot's decision-making ability and concentration may have been impaired by distractions and fatigue. The accident was not survivable.