What happened
On the morning of 19 January 2002, a Cessna 207, registration ZK-SEV, departed Te Anau Aerodrome bound for Milford Sound. The flight was an air transport operation carrying the pilot and five passengers. The aircraft followed a route through the Eglington Valley, maintaining contact with a lead aircraft and flight services throughout the initial stages of the flight.
As the aircraft approached the Gertrude Saddle area, approximately 11 kilometers southeast of Milford Sound, it struck the side of a mountainous valley at an altitude of roughly 4400 feet. The impact occurred near Black Lake, 500 meters southeast of the saddle. The collision resulted in 6 fatalities, including the pilot and all five passengers on board. Following the impact, a helicopter pilot discovered the wreckage and confirmed there were no survivors.
The investigation
Investigators examined the flight history, weather conditions, and the pilot's experience. The weather at the time of the accident was clear, with blue skies and a southeasterly tailwind. The aircraft was found to be airworthy and properly maintained. The investigation focused on the aircraft's flight path and the pilot's maneuvers as the plane approached the steep terrain of the Gertrude Valley.
Findings
Analysis of the flight path suggests that the aircraft was likely at an insufficient altitude to safely traverse the Gertrude Saddle. It is believed the pilot may have misjudged the impact of the tailwind on ground speed or failed to account for potential downdrafts. Upon realizing the height was inadequate, the pilot likely attempted a left reverse turn to escape the valley, but this decision was made too late to avoid the terrain.
Other contributing factors included the pilot's relatively limited experience in such demanding mountain environments and the lack of mandatory mountain-flying training for aeroplane pilots.