Authorities in Australia today concluded that the cause of a dangerous plummet by a Qantas airliner last week resulted from the malfunction of an onboard navigation computer, not from interference by a passenger's electronic device as was first suspected.
According to a news item today in the The Sydney Morning Herald, the Qantas jet's air-data inertial reference unit sent "erratic and erroneous information" to the plane's flight control system, taking command of the aircraft out of the pilot's hands.
The dramatic 650-foot fall of Flight QF72 from 37 000 feet over the Indian Ocean, flying from Singapore to Perth, resulted in dozens of serious injuries to its passengers, according to an article from Britain's Telegraph. After retaking manual control of the A330-300 Airbus, the Qantas pilot was able to safely land the aircraft at an air force base in Learmonth, Western Australia.
An early account from the U.K.'s VNUnet raised the question of whether the high-altitude incident was brought about by the unauthorized use of a wireless device by a passenger.
The Australian Transport Safety Bureau (ATSB) interviewed all passengers after de-boarding the stricken plane on their usage of electronics during the episode but found no evidence of improper activity.
"Certainly in our discussions with passengers that is exactly the sort of question we will be asking: 'Were you using a computer?'" an ATSB representative said shortly after the incident.
The in-flight use of wireless devices, such as cellphones and laptops, has been a source of ongoing concern in recent years among aviation authorities.
A leading advocate of restraint in wireless usage aboard passenger aircraft wrote in a March 2006 IEEE Spectrum feature (Unsafe At Any Airspeed?) that he and his colleagues have "doubts that such use [is] safe."
IEEE Fellow M. Granger Morgan, head of Carnegie Mellon University's department of engineering and public policy, wrote in our pages: "In an industry that has eliminated or is effectively managing most large and obvious sources of danger, such small but persistent risks warrant serious attention. At present, we believe that passenger use of electronics on board commercial aircraft should continue to be limited and that passengers should not be allowed to operate intentionally radiating devices such as cellphones and wireless computer equipment during critical stages of flight."
In the case of Qantas Flight QF72, the danger posed by wireless electronics has proven to be a false lead, according to the Australian investigators. Still, the issue was controversial enough to pop up prominently as the possible cause of a potentially disastrous aircraft accident.
That makes it an issue that is not going to be resolved soon. There is just too much at stake.