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A comment on Fliers Must Turn Off Devices, but It’s Not Clear Why. Parent comment

Re:Fliers Must Turn Off Devices, but It’s Not Clear Why by wglb on Sunday November 27, 2011 @07:54PM (#3283940)
Inside your iPod nano, or any other device with a computer chip is a radio transmitter. Inside the cockpit are many radio receivers, some of which are pretty critical to the proper flight of the airplane. Your radio transmitter, and radio transmitters being run by other passengers, mix and mingle their signals, producing an unpredictable effect on these key cockpit receivers.

The probability that this happens is not zero or low, but very high.

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Re:Fliers Must Turn Off Devices, but It’s Not Clear Why by orangecat on Sunday November 27, 2011 @08:06PM (#3283973)
The probability that this happens is not zero or low, but very high.

No, it isn't. If it were, we wouldn't be depending on the honor system.

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Re:Fliers Must Turn Off Devices, but It’s Not Clear Why by aceofspades19 on Sunday November 27, 2011 @08:45PM (#3284074)
1. Not all devices with a computer chip have radios, my TI-84 calculator has a Z-80 processor but there is no radio in it 2. Aircraft radios operate on a very different frequency then consumer electronics, and I'm pretty sure the FCC wouldn't allow consumer electronics to operate on the same frequency as the radios in a cockpit regardless
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Re:Fliers Must Turn Off Devices, but It’s Not Clear Why by CamperBob on Sunday November 27, 2011 @09:13PM (#3284133)
Technically, yes, there is a "radio" in your TI-84. The Z-80 is clocked by a crystal oscillator, which runs at a few MHz. Some of that energy will escape in the form of electromagnetic radiation. Sensitive instruments (including an ordinary AM radio) can pick up this radiation from distances ranging from a few inches to several yards. This is true of essentially all modern electronics, although the frequencies have obviously gone higher and higher over time.

If it were true that the RF energy levels emitted by FCC Part 15-covered consumer electronics could interfere with aircraft systems, it would be utterly unthinkable to permit them on board in the first place, whether "powered off" or not. The TSA would be confiscating Game Boys, not bottles of water. Since that isn't happening, it's difficult to avoid the conclusion that the prohibition is just one more exercise in bureaucratic security theatre.

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Re:Fliers Must Turn Off Devices, but It’s Not Clear Why by andrewescott on Sunday November 27, 2011 @11:22PM (#3284516)
If all electronic devices were dangerous, airlines would be asking passengers to remove the batteries from their wristwatches for the duration of the flight.
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