AFP, Sydney, A Qantas plane plummetted more than 1,000 feet in 38 seconds, flinging passengers around the cabin, partly because of a design limitation in the flight control software, an Australian probe found on Monday. More than 100 passengers and crew were injured, 12 seriously, during the two nose-down drops by the Airbus A330-303, en route from Singapore to Perth, as it flew at 37,000 feet off Australia's northwest coast on October 7, 2008. In its final report on the matter, the Australian Transport Safety Bureau (ATSB) said the dives were caused by the combination of a design limitation in the flight control primary computer software and another misfiring instrument. That instrument was one of the Airbus' three air data inertial reference units (ADIRUs) -- devices which provide information on airspeed and other critical flight parameters to the plane's main computer. "This limitation meant that, in a very specific situation, multiple AOA (angle of attack) spikes from only one of the three air data inertial reference units could result in a nose-down elevator command," it said. Read Full: Qantas flight dive due to software limitation | The Asian Age
