Threat of electronics on planes hazy, but rules are clear

They may seem like silly rules -- turn off all cellphones and electronic devices during takeoff or landing of a plane. And, no cellphone use during the flight.

Those are the rules "30 Rock" star Alec Baldwin was accused of breaking when he was kicked off an American Airlines flight on Dec. 7 after refusing to power down. The actor vented on Twitter that he was berated by a flight attendant for playing a game while the plane sat at the gate not moving.

But why all the fuss?

Decades ago the Federal Aviation Administration and the Federal Communications Commission determined that electronic devices could send signals that would interfere with the equipment on an airplane, officials said. Therefore, all electronic games, MP3 players and laptops have to be turned off until the plane gets above 10,000 feet.

Cellphones are not to be used for calls or Internet use on a cellular network anytime the plane is in the air, though they can be used in "airplane mode" for such activities as playing games.

Brent Bowen, the head of the Department of Aviation Technology at Purdue University, said there is little research to show if personal electronic devices actually cause a problem. But that doesn't matter.

"It's a federal air regulation, and the crew is responsible for enforcing it," he said. "These rules apply to all airlines in America and all airlines operating in America."

According to their written explanation, there are too many unknowns about the radio signals that hand-held electronics and cellphones give off. At lower altitudes, any interference could be more of a safety hazard, because the pilot and cockpit crew need to focus on critical arrival and departure duties, the FAA said in its statement.

As for Wi-Fi systems now available on some flights, manufacturers must obtain certification from the FAA showing they do not interfere with the plane's systems anytime during flight, the FAA said.