What happened
On 18 October 2018, an MD 500D helicopter, registered ZK-HOJ, departed Wānaka Aerodrome as part of a wildlife management mission for the Department of Conservation. The aircraft was carrying a pilot and two workers, along with various equipment including rifles, ammunition, and extra fuel containers.
Shortly after takeoff, while climbing to approximately 500 feet, the helicopter experienced a sudden and violent mid-air breakup. Witnesses at the aerodrome observed the aircraft descending almost vertically and spinning uncontrollably. During the descent, various items were seen being ejected from the cabin. The helicopter eventually struck the ground and caught fire. There were 3 fatalities in the accident, as none of the occupants survived the impact.
The investigation
Investigators from the TAIC reconstructed the sequence of events by examining digital camera footage from the aerodrome and analyzing wreckage. The investigation focused on the mechanical state of the aircraft's doors and the stability of the cargo within the cabin.
Evidence showed that the aircraft's rear cabin contained several unsecured items, including heavy fuel containers and personal clothing. The investigation also examined the physical condition of the left-rear door-latch mechanism, which showed signs of wear. Furthermore, the inquiry looked into the regulatory definitions of "crew" versus "passengers" to determine if ambiguities in aviation rules contributed to the operational environment of the flight.