The ATSB has released its investigation report into the 18 November 2009 ditching of an Israel Aircraft Industries Westwind 1124A that occurred off Norfolk Island. The report found that the need to ditch the aircraft arose from incomplete pre-flight and en route planning and the failure to assess that a safe landing could not be assured before it was too late to divert. The investigation also confirmed the benefit of clear in-flight weather decision making guidance and its timely application by pilots in command.
The flight was an aeromedical retrieval from Apia, Samoa bound for Melbourne via Norfolk Island. It was carrying a pilot in command (PIC), copilot, a doctor, a nurse, a patient and one passenger. The pilot submitted a flight plan to leave Apia bound for Norfolk Island, a journey of four and a half hours.
The PIC received the latest aerodrome forecast (TAF) for Norfolk Island from the briefing officer while submitting the flight plan. The forecast was valid beyond the period of the flight and indicated that the weather conditions would be suitable for landing. Based on that forecast, there was no requirement to plan or to carry fuel for the possibility of a diversion to an alternate airport.
Various weather reports and forecasts, both routine and special, were available en route through air traffic control. Special weather reports (or SPECIs) are issued when there is significant deterioration or improvement in airport weather conditions. The flight crew did not realise the significance of the changed conditions reported in a SPECI for Norfolk Island until after they had committed to landing on Norfolk Island. By this time they had insufficient fuel reserves to divert to another destination.
The crew attempted a night approach and landing on Norfolk Island, but the weather conditions prevented them from seeing the runway or its visual aids, and therefore, from landing. After four failed attempts, the PIC elected to ditch the aircraft in the sea 3km south-west of Headstone Point on Norfolk Island, before its fuel was exhausted. The aircraft broke in two after ditching. All the occupants escaped from the aircraft and were rescued by boat, although two sustained serious injuries.
The report found that the operator's procedures and flight planning guidance managed risks consistent with regulatory provisions but did not minimise the risks associated with aero-medical operations to remote islands. Clearer guidance on the in-flight management of previously unforecast, but deteriorating destination weather might have assisted the crew to consider and plan their diversion options earlier.
As a result of this accident, the operator changed its guidance for the management of previously unforecast deteriorating destination weather. Satellite communication has been provided to crews to allow more reliable remote communications and its flight crew oversight systems and procedures have been enhanced. CASA is also developing a number of Civil Aviation Safety Regulations covering fuel planning and in-flight management, the selection of alternate destinations and extended diversion time operations.