Reconsidering digital devices at takeoff and landing

Does it really matter if we turn off our digital devices before the plane takes off?

Know how you have to turn off your Kindle when you're on a plane, at least when you take off and land? The FAA is asking for public comment on those rules.

Jay Apt is a professor at Carnegie Mellon's Tepper School of Business. He says, "You have a Wi-Fi card in your laptop or your iPad, you have of course a radio in your cell phone, and if those things are pumping out radio waves, they can interfere with the navigation and control systems of the airliners."

There are two ways digital devices cause problems. Kenneth Kirchoff is an engineer from Boeing. He calls the first front door interference: "Emissions from devices that are unintentional that are actually in the same frequency as the radios that are used on the airplane, so that energy gets out of the airplane, gets out through the windows and doors and things like that and it couples onto the airplane antennas because it's in the same frequency and can interfere with those radio devices, such as navigation equipment or surveillance equipment."

The second: back door interference. "And that's when you have the intentional emissions from a cell phone or a Wi-Fi device where that intentional signal that's being radiated can couple onto wiring or it can couple directly into the systems on the airplane and cause some sort of interference with those systems," says Kirchoff.

Back to Jay Apt. He's done research that shows the interference can be a problem. "In about a half a dozen incidents, the flight crew identified the personal electronic device, had the passenger turn it off, saw the navigation error went away, and then had them turn it back on again and then saw the navigation error recurred, and then of course had it stowed for flight, so we were convinced that these kind of errors, while rare, are real, and when an airliner is speeding close to the ground on a foggy day trying to get into New Orleans before a hurricane strikes, you really want all the navigation systems to be working just fine."

Boeing's Kirchoff says devices like the Kindle might not be so bad. "When that device is operating just as a book, and it's not transmitting anything, in that kind of a mode, it's certainly from an electromagnetic standpoint isn't going to interfere, or shouldn't interfere with the airplane."

He says there are still reasons you might not be able to keep your Kindle out at takeoff and landing. For one, it’s hard to police whether your device is in airplane mode plus airlines want you to pay attention to those safety announcements.

One thing not up for discussion, cell phone calls. Those are prohibited by the Federal Communications Commission.


And now from the files of sci-fi-inspired technology.

Researchers have figured out how to hack into our brains.

"Invasion of the Body Snatchers" clip: They will absorb your mind...your memories.

Or at least get a better guess of what's in there. Scientists, using a couple-hundred-dollar brain computer interface headset, were able to pick up subconscious activities. And use those signals to help figure out research subjects’ PIN numbers, even which house they live in.

In the future, you could use these headsets to play video games. But you might want to be careful. Because while you're playing games, hackers could read all your brain data and use it against you.

About the author

Adriene Hill is a senior multimedia reporter for the Marketplace sustainability desk, with a focus on consumer issues and the individual relationship to sustainability and the environment.
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I just wish the rules were applied uniformly for all devices and all passengers. They often seem to be up to the discretion of the flight attendant and whether she/he takes a liking to the individual passenger. More than once I have had flight attendants tell me personally that I must put away my Kindle while the plane was still boarding (and people were trying to cram their oversized luggage into the overhead bins). Meanwhile the person across the aisle was happily texting away on the iPhone and no one said a word to her.

That's just a case of an overzealous flight attendant (or one having a rough work day). I believe they generally want you to power down your gizmos once the aircraft pushes back from the gate (taxiing, when the nav instruments need to establish a strong lock-on before taking the runway), and above 10,000'. While the plane's being boarded, the pilots may not've even completed their before-engine-start checklist. No need to stop reading.

As to device reference, using brand names may help recognition, but why not describe them by use: digital eBook reader, tablet computer (iOS, Android), handheld mobile device (Android, iOS, Windows Mobile). We know Adrienne's all about her Kindle, now I wanna hear what Kai, Paddy, and Tess travel with. ;)

That doesn't explain why my e-reader with the Wifi and/or 3G turned off has to be stowed while other passengers can still use their phones.
Next time I'll just load my books into the Kindle app on my iPhone and I'll be good to go! LOL

Ms. Hill repeatedly and specifically mentioned the Kindle. Does that mean this information does not apply to we users of other devices? The professor interviewed seemed to suggest this story does apply to all mobile devices. If so, why is Ms. Hill mentioning one specific brand and product? Over at NPR they talk as though everybody uses an iPhone or iPad. Now, APM talks as if the Kindle is the only device out there (it's not). When you people are talking about a product category or industry, you should use a generic name. Don't they teach this stuff in journalism schools any more?

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