Did Wi-Fi interference cause Boeing 777 crash?

The recent BA038 crash-landing at Heathrow airport may have been caused by interference from wireless networks, which affected the aircraft's electronically controlled power and automated flight systems.

The recent BA038 crash-landing at Heathrow airport may have been caused by interference from wireless networks, which affected the aircraft's electronically controlled power and automated flight systems.

Nina Anderson, author of 'Worse Than Global Warming -- Wave Technology' has speculated that interference from rogue radio frequencies could have influenced the aircraft's "brain", causing one or more of its electronically-controlled systems -- such as the auto-pilot, auto-throttle and power management -- to fail.

However avionics experts remain reserved about such claims, preferring to blame 'dirty fuel' from Beijing on both engines failing.

Initial reports from the UK Air Accidents Investigations Branch, which is investigating the crash, have confirmed that the auto-throttles did not respond as the aircraft approached landing.

Since the auto-throttle is controlled via the aircarft's electronic systems, wireless interference is one possible explanation, according to Paul Cousins, federal president of the Australian Licensed Aircraft Engineers Association (ALAEA). However, he said there are several other possibilities.

"As to why this occurred there are numerous possible reasons, ranging from electronics, or dirty fuel, to the engines themselves. At this time, obviously, I wouldn't like to speculate because the information is not at hand," Cousins told ZDNet.com.au.

Although Anderson's theory cannot be substantiated until investigations have concluded, Cousins -- who has worked on Boeing's 737-800, all the 737-series and the 767 -- said that besides the soon-to-be-launched Boeing 787, the 777 has the most electronically-controlled components of all commercial aircraft.

"On [the 777] there are a vast number of systems that are controlled electronically. When it was created that was the beginning of the electronics-age for that aircraft, so almost every system -- auto-pilot, auto-throttle, power management, and so on -- on that aircraft would have some electronics input," he said.

One system he believes would not be at fault in this instance -- despite recent concerns the Boeing 787's electronic-systems could be hacked through its passenger entertainment systems -- is the passenger entertainment system.

"This particular aircraft has been around for a number of years. If there were any hiccups in the passenger entertainment system such as Wi-Fi access or telephone-use onboard it would have been picked up by now," he said.

However ALAEA's federal secretary, Steven Purvinas, an avionics engineer with 20 years experience, contacted members of the organisation who had worked on the Boeing 777. He told ZDNet.com.au that of all Boeing's aircraft, the 777 is most likely to be affected by wireless or radio frequency interference.

"The 777 is far more electronically capable and reliant on it than its predecessors such as the Boeing 747. If wireless interference hasn't been ruled out as a possible cause, this aircraft would be a prime candidate for it," said Purvinas.

According to the members of the ALAEA who have worked on Boeing 777 aircraft, but declined to be interviewed, Boeing has taken extra measures to secure the systems and wiring that connect those systems.

The engineers claimed that although the 777 relies more on its electronic components, its wiring bundles are heavily shielded against radiation and stray currents that might affect the integrity of the system.

A more likely cause of the aircraft's throttle systems to fail at that stage of descent, according to Purvinas, is dirty fuel from Beijing, where it had refuelled before heading to London's Heathrow Airport.

"In this case, we're talking both engines carking it at same time. At that stage the aircraft is tilted at a certain altitude so when the fuel moves back into the tanks, it may expose the fuel pumps to water which is contained in the tanks," he said.

A small amount of water is not uncommon in fuel, Purvinas said.

"When you're putting in a hundred thousand kilos of fuel, there is a small component of water but if that all rises to the top of the fuel tank and is exposed to the fuel-pump intakes at same time, that is when you may have a problem at the same time on both engines," he said.