The airline industry reported this week that there is a clear and present danger when passengers use a cell phone after takeoff, saying it will throw the aircraft navigation systems for a loop.
A new report by the International Air Transport Association documents 75 separate incidents of possible electronic interference that airline pilots and other crew members believed were linked to mobile phones and other electronic devices.
It documented the years between 2003 to 2009 and is based on 125 different airlines, which accounts for a quarter of the world's air traffic.
There are frightening statistics revealed in the report, which logged 26 of the incidents affected the flight controls, including the autopilot, and landing gear. Seventeen flights showed flawed navigation systems, while 15 communication systems were compromised. Thirteen of the incidents produced electronic warnings, including "engine indicator lights."
According the report, electronic devices that were activated on the airplane caused GPS and altitude-control readings to read incorrectly and change rapidly.
The type of electronic device suspected in every incident were cell phones, which are now linked to four out of 10 in-flight navigation problems.
The airplane instrument readings reportedly returned to normal after crewmembers made passengers turn off their devices, according to report data.
"We found that the risk posed by these portable devices is higher than previously believed," said Bill Strauss, who conducted a study with other researchers on cell phones and airplanes at Carnegie Mellon University.
"These devices can disrupt normal operation of key cockpit instruments, especially Global Positioning System receivers, which are increasingly vital for safe landings."
Strauss is an expert in aircraft electromagnetic compatibility at the Naval Air Warfare Center in Maryland.
That study also revealed cell phones and other portable electronic devices, like laptops and game-playing devices, can pose dangers to the normal operation of critical electronics on airplanes.
Previous studies have shown that there is no real evidence of accidents caused by cellphones but that using them in flight can be more dangerous than was understood before.
"We can't say categorically that these devices cause interference," said IATA spokesman Chris Goater.
"But there are enough anecdotal reports from pilots to raise the question."
Frequent flyers like Phil Walsh, a businessman from Mobile, Ala., said he thinks cell phones are too small to cause cancer and to cause airline navigation systems to go haywire.
“It just does not seem like there is any common sense in these new studies about cell phones,” Walsh said.
“I have been flying for more than a decade. I have always sneaked and used my cell phone and laptop. Never heard of any problems and landed safely every time.”
Finding that direct link between airline navigation systems and mobile phones may take a while, researchers said.
The Federal Communications Commission’s regulation banning cell-phone use on airplanes has been in place since 1991, but recent studies show that passengers are not taking the rule seriously.