"Certainly, there was a period of time when the aircraft performed of its own accord."

Not quite "Open the pod bay doors, HAL," or Dr. Daystrom on the Enterprise, but pretty scary stuff.

Julian Walsh, director of aviation safety at the Australian Transport Safety Bureau, said an on-board electronic centralized aircraft monitoring system indicated there was "some irregularity with the elevator control system."

The aircraft departed from its normal flight at 37,000 feet, climbed 300 feet, "then as the crew were responding, the aircraft pitched down quite suddenly and rapidly," he said.