Airlines Cell Phones
Why do airlines make you turn off your cell phone before takeoff and landing? REUTERS

Why do airlines make you turn off your cellphone before takeoff and landing? It's a question many have asked since the Alec Baldwin debacle on American Airlines last week - and while the rule is clear, the answer is decidedly foggy.

On Saturday, Baldwin made a cameo appearance on SNL, posing as the pilot of the American Airlines flight he was removed from last week, in part, for refusing to turn off his cellphone in order to continue playing the Scrabble-like game Words With Friends.

Baldwin later complained that he was being made an example of and that other passengers continued to use their phones and portable electronic devices while he was singled out.

Dressed as Capt. Steve Rogers, Baldwin called electronics rules a cruel joke perpetrated by the airline industry, asking would you really get on an airplane that flew 30,000 feet in the air if you thought one Kindle switch would take it down.

He makes a good point. Most of us probably wouldn't get on a flight if we thought that flipping on an electronic device at the wrong moment would take the plane down.

A recent Poll Position survey found that 70% of 18-29-year-olds think passengers on a plane should be able to play electronic games with others while on the runway awaiting takeoff.

So why do airlines make you turn off your phones, laptops, iPads, iPods, eReaders, and other electronic devices? Can a cellphone really interfere with a plane's systems and avionics so much that it poses a safety threat?

The answer is that it's highly unlikely, but possible.

In 1991, the U.S. Federal Aviation Administration (FAA) and the Federal Communications Commission (FCC) determined that electronic devices could send signals that would interfere with the plane's equipment. It was determined that all electronic devices should be turned off until the plane is above 10,000 feet.

According to a fact sheet issued by the FAA, there are too many unknowns about radio signals that hand-held electronics give off. Because the pilot and cockpit crew need to focus on critical arrival and departure tasks, the FAA believes that any use at lower altitudes could interfere and become a safety hazard.

Even if not engaged in a call, a cellphone's power-on mode sends out bursts of potentially dangerous energy.

Portable electronic devices are designed to radiate and receive signals which could be picked up by one of the many antennas you'll see attached to modern passenger aircraft, Gregg Overman, Director of Communications for the Allied Pilots Association, the collective bargaining agent for American Airlines pilots, told the Wall Street Journal. Those antennas send signals to wiring that is connected to key systems such as the autopilot, cockpit instrumentation and so forth.

In many airport environments, airplanes follow highly precise routing designed to maximize inbound and outbound traffic levels, Overman added. Any deviation from those routings is not a good thing. Passengers need to recognize that restrictions on the use of portable electronic devices exist for good reason.

While this policy of turning off electronic devises is clear, it's relatively unenforced and depends on a so-called honor system - which leads one to ask, if so many cellphones are likely switched on during takeoff and landing, why hasn't a plane fallen out of the sky by now?

Many like New York Times writer Nick Bilton argue that very little research has been done to determine whether the ban on electronic devices during takeoff and landing should be relaxed - and further studies are unlikely. From an airline's standpoint, asking passengers to cut off their devices for no more than 30 minutes each flight far out ways funding extensive surveys.

A 2006 study commissioned by the FAA and carried out by the Radio Technical Commission for Aeronautics, a nonprofit group that tests and reports on travel systems, found insufficient information to support changing the policies.

Confusingly, several airlines now use Wi-Fi systems. However, the FAA says that manufacturers must obtain certification from the agency showing that they do not interfere with the plane's systems anytime during the duration of the flight.

There are other exceptions to the rule, according to the FAA. The regulations specifically exempt hearing aids, portable voice recorders, pacemakers, and electric shavers because they do not give off signals that might interfere with aircraft systems.

While the Alec Baldwin row presents an interesting question, until there is definitive proof that cellphones and other electronic devices pose no threat to aviation safety, it's best to follow the rules, lest you be kicked off a plane.