What happened
On Wednesday, 19 August 1998, a Cessna 402C, registration ZK-VAC, was conducting a scheduled flight from Stewart Island to Invercargill. During the flight, the aircraft experienced a simultaneous failure of both engines. The pilot managed to perform a successful ditching in the waters of Foveaux Strait.
While five passengers were successfully rescued from the aircraft, the accident resulted in four fatalities and one person remains missing and presumed dead. The fatalities included the pilot and three passengers who were not wearing lifejackets at the time of the ditching.
The investigation
The investigation focused on the circumstances leading to the loss of power in both engines. Investigators examined the mechanical state of the aircraft and the operational procedures used during the flight. A key area of scrutiny involved the fuel management processes and the accuracy of the information available to the crew regarding fuel levels.
Findings
While the investigation could not definitively determine the exact reason for the dual engine failure, evidence suggested the event may have been linked to systemic fuel management issues.
Safety action
Following the investigation, several safety concerns were identified regarding how fuel levels are monitored and how aircraft equipment is documented. The findings highlighted a need for operators to implement fuel quantity monitoring systems to provide a secondary check to standard fuel gauge readings. Additionally, the investigation emphasized that aircraft flight manuals must clearly state the presence of any optional equipment that could impact flight operations. A formal safety recommendation was issued to the Director of Civil Aviation regarding the clarity of aircraft flight manuals.