WHETHER electronic devices on airplanes can cause problems is the subject of hot debate. Opinions range from those who are convinced that they pose no danger to those who are equally sure that they are deadly. There are yet others who are ambivalent and unsure about their effects.

A local expert said while the dangers posed during flight take-offs and landings were confirmed, there had been no proven connection between electronic gadgets and safety issues in mid air.

Several airlines have begun equipping airplanes with picocells to allow passengers to use mobile phones on board.

This has been met with great enthusiasm from mobile telecommunications associations.

Australian Mobile Telecommunications Association chief executive Chris Althaus welcomed Qantas and V Australia's recent announcements that they were introducing mobile phone services to their passengers on selected flights.
He said the association supported the introduction of the services, which had been fully tested to ensure that they met all safety standards and complied with aviation authority requirements.

He added that the system was safe and had been fully tested by aviation and communications regulatory agencies.

However, Australian electromagnetic interference (EMI) specialist Chris Zombolas said large-scale usage of such devices in flight increased the risk of EMI.

He said the case of Qantas QF72 could have been caused by exactly such a situation.

Zombolas, in an article for an Australian publication, slammed the relaxation of rules regarding in-flight mobile phone usage as sending the wrong message to passengers. He said the installation of picocells on planes did not take into account human factors such as passengers defying the rules and the ever-changing wireless technologies in consumer devices.

"Laptop computers and personal digital assistants can have six or more different transmitters and the number is growing.

"The laptop/PDA transmitters are mostly set to automatically transmit when they are powered up.

"In the United States, the Federal Aviation Administration (FAA) and the Federal Communications Commission are the regulators responsible for aircraft safety and communications respectively.

"The FAA has documented cases of electromagnetic interference to aircraft systems.

"It is yet to be convinced that safety and effective communications will not be compromised, and is awaiting the results of further research before considering lifting restrictions on using these devices in-flight."

Furthermore, said Zombolas, a Carnegie Mellon University study in 2006, which monitored mobile phone and portable electronic device usage on 37 US commercial flights, indicated that the risk of interference to a plane's navigation system was indeed real.

"Alarmingly, one of the researchers, Bill Strauss -- an expert in aircraft EMI in the US Naval Air Warfare Centre -- concluded that the risk posed by these portable devices is higher than previously believed.

"These devices can disrupt normal operation of key cockpit instruments, especially Global Positioning System receivers, which are increasingly vital for safe landings."

The study also found that one to four mobile phone calls were made during each flight, despite rules prohibiting them.

The Australian Transport Safety Bureau has not discounted the possibility that electronic items could have caused the QF72 incident.

However, several press reports in Australia indicated that the fault lay not with electronic devices operated by passengers, but with the airplane's control software itself.