Eight people were killed yesterday when a light plane depressurised and crashed in Australia's remote northeast, after flying 3,000 kilometres on a five-hour ghost flight across the continent.
Air safety investigators have arrived at the crash site just south of the Gulf of Carpentaria to investigate if the plane depressurised and emergency oxygen units failed to operate, or if it failed to pressurise at the outset, leaving the pilot and seven passengers unconscious.
The Beechcraft King Air 200 twin-engine turboprop set out with seven miners on a one-hour flight from Perth to the gold mining town of Leonora, both in Western Australia. It crashed five hours later on the other side of the continent, 80 nautical miles south-west of Normanton, authorities said.
The alarm was raised 32 minutes after takeoff when authorities noticed the plane climbing higher than its assigned flying altitude of 25,000 ft, reaching heights of 34,000 ft.
"Initially, the plane maintained the 25,000 ft but then Air Traffic Control saw the aircraft climb through that and asked the pilot what was his intention," Mr Barry Sargeant of the Australian Transport Safety Bureau said. "The pilot said "stand by", but after that there was no further response. Various attempts were made to contact the pilot but when they were unsuccessful and the aircraft was still climbing, an emergency was declared."
Mr Sargeant said first, a light plane from Perth and then two planes from Alice Springs in central Australia shadowed the King Air, but reported no signs of stress or obvious malfunction.
A senior investigator with the aviation division of Australian Search and Rescue, Mr Michael Lawton, said the planes tracked the King Air as it flew virtually in a straight line across three states before running out of fuel and crashing in remote bushland.
A post mortem investigation in Brisbane will determine if the seven passengers and pilot died while the plane was flying on autopilot, or if they died when the plane crashed.