What happened
During a scheduled mail delivery service traveling from Wellington toward Christchurch, the pilot was operating at flight level 100. While beginning the descent toward the destination, the pilot contacted air traffic control to report technical difficulties. Shortly thereafter, an emergency was declared following the shutdown of one engine. Within seconds of this event, the aircraft entered an uncontrollable spin and impacted the ocean surface. Despite the launch of search and rescue operations, neither the aircraft nor the pilot could be located.
Findings
Because no wreckage or remains were recovered, investigators were unable to establish a definitive cause for the accident. However, several potential scenarios remain under consideration by authorities. These include the possibility that the pilot experienced spatial disorientation while managing the engine failure in low-visibility cloud conditions. Other factors that have not been dismissed include airframe icing, an engine bay fire resulting from structural failure, an explosion involving dangerous goods, a malfunction within the flight control systems, or intentional interference.