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Panel Advises FAA to Lift All Wi-Fi Use Restrictions
by Karl Bode 08:00AM Thursday Oct 03 2013
A Federal Aviation Administration advisory committee "has concluded passengers can safely use hand-held electronic devices, including those connected to onboard Wi-Fi systems, during all portions of flights on nearly all US airliners," according to a paywalled report in the Wall Street Journal. Last week reports emerged that the FAA was preparing to lift in-flight restrictions starting early next year, though the panel's recommendations go further than expected. Cell phone conversations would remain off limits according to the committee's recommendations.

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batterup
I Can Not Tell A Lie.
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join:2003-02-06
Netcong, NJ

Words with friends anybody?



Nightfall
My Goal Is To Deny Yours
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join:2001-08-03
Grand Rapids, MI
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Not surprising

Mythbusters already did a piece on this years ago. That and there are a lot of people who don't turn off their electronic devices before takeoff and before landing. I see them put their devices away, but they are not off. If this were a real problem, then planes would be crashing more often than not or there would be more reports of problems.
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My domain - Nightfall.net
ptbarnett

join:2002-09-30
Lewisville, TX

Re: Not surprising

I'm really amazed at all the self-appointed experts on this issue.

Radio interference doesn't "crash planes". But, it interferes with the pilot's ability to communicate and navigate. Fortunately, they have backups, but it can be just one more link in the chain of events that leads to an incident.

Lots of people text on their cell phones while driving, and don't crash. But, that doesn't make it safe. All it takes is one unexpected occurrence while distracted....

Boricua
Premium
join:2002-01-26
Sacramuerto

Re: Not surprising

You probably missed the part Nightfall See Profile said

If this were a real problem, then planes would be crashing more often than not or there would be more reports of problems.

I, for one, never turned off my iPod. I have it on so I can potentially go to sleep. Now, cell phone I always put on airplane mode. I didn't care if the attendants said (as they did on one flight), to turn off devices even if it's on airplane mode.
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Illegal aliens have always been a problem in the United States. Ask any Indian. Robert Orben
ptbarnett

join:2002-09-30
Lewisville, TX

Re: Not surprising

said by Boricua:

You probably missed the part Nightfall See Profile said

If this were a real problem, then planes would be crashing more often than not or there would be more reports of problems.

NASA runs a database of pilot and crew reported problems (it's called ASRS), and you can find plenty of reports of interference -- at least when service is restored.

I also pointed out the fallacy of "there haven't been any crashes, so there is no problem". Maybe this example will help you to understand the concept of a false correlation:

I have a rock. Since I've had this rock, I've never been attacked by a tiger. Therefore, this rock must be protecting me from tigers.

Let's reword this a bit:

I have a cell phone. I never turn it off when I fly on an airplane, and I've never been in an airplane crash. So, my cell phone must not cause any problems.

r81984
Fair and Balanced
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Katy, TX
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I hope you know that aircraft equipment is shielded or parts of the aircraft would cause interference with each other.
Your less than 1 watt devices like cell phones and laptops are not strong enough to do anythigng to an airplane.
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r81984
Fair and Balanced
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join:2001-11-14
Katy, TX
My phone stays on the entire flight in my bag. I dont even bother opening my bag to turn it off on any flight.
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AlexNYC

join:2001-06-02
Edwards, CO

What a shocker!

WOW, really? You mean cell phones and tablets which are certified by FCC not to interfere with other things actually don't interfere with planes? No kidding, who would have thunk it!

Next thing you know we won't have to take our shoes off at the annoying TSA screening which by the way has never caught any bag guys.
ptbarnett

join:2002-09-30
Lewisville, TX

Re: What a shocker!

said by AlexNYC:

WOW, really? You mean cell phones and tablets which are certified by FCC not to interfere with other things actually don't interfere with planes? No kidding, who would have thunk it!

That's not what FCC certification says. All it says it that any transmitted RF above a certain signal level is within the licensed frequency band(s), and that any transmitted RF (harmonics, oscillators, etc.) outside those licensed bands is below a certain signal level. It doesn't mean there are zero emissions outside the licensed band. That's nearly a physical impossibility.

It doesn't say that it won't interfere with other devices. The other devices may certified to reject or tolerate interference, but only below certain signal levels. And, if something is inadvertently transmitting right on top of the desired signal, it can block the aircraft radio. In some phases of flight, the signal can be very weak.

I won't bore you with all the technical details, but two devices transmitting on different frequencies in close proximity can generate a signal on a third frequency. Look up "intermodulation" if you want more information.

AlexNYC

join:2001-06-02
Edwards, CO

Re: What a shocker!

What you wrote just proves my point, and is the reason why they are lifting the ban.

We all know what frequencies cell phones and wifi uses. They are all licensed by the FCC.

The airplane com equipment is designed not to be bothered in general by those known licensed frequencies.

Now obviously I don't recommend anyone using a CB radio or police scanner in the airplane.

And as far as two devices generating a third frequency that can interfere, I think your chances of winning the lotto are much higher is real life.
ptbarnett

join:2002-09-30
Lewisville, TX

Re: What a shocker!

said by AlexNYC:

We all know what frequencies cell phones and wifi uses. They are all licensed by the FCC.

Yes, and some of them are very near the aircraft communication and navigation frequency bands. GPS downlink frequencies are at 1.2 and 1.6 GHz. That signal is already just barely about the noise threshold, and it doesn't take much to interfere with it.

And I don't think you are understanding: A transmitter generates harmonics on multiples of the original frequency. Their power level is much lower, and it depends on the waveform that is used (sine, square, etc.). But, without filters that won't fit in a consumer device, you can't eliminate them.

said by AlexNYC:

The airplane com equipment is designed not to be bothered in general by those known licensed frequencies.

If that were true, there would be no problem. But, it's a lot more complicated than just the radio. The antennas are typically mounted on the belly of the aircraft, and you may be sitting right over it. Or you may be sitting close enough to the cockpit to interfere with the cockpit audio system. Newer aircraft avionics are more resistant to interference, but there are plenty of older systems still in service.

said by AlexNYC:

And as far as two devices generating a third frequency that can interfere, I think your chances of winning the lotto are much higher is real life.

It's pretty rare. But, it does happen. You can do a search through NASA's ASRS database and you'll find many reports of interference. Do you want to bet on whether it will interfere with a pilot's navigation or communication at a critical moment? As I wrote above: just because have been texting while driving and haven't had a crash, does that mean it is safe?

I have both a pilot's license and an amateur radio license. I've personally experienced interference, and sometimes I caused it (I was in my own plane, in VFR conditions).

I think it's reasonable to allow use of portable electronic devices during all phases of flight, because they are much better shielded than in the past. But, transmitters of all kinds (WiFi, cell, bluetooth, etc.) should be turned off during the takeoff and landing phases -- generally below 10,000 feet. It's during that phase of flight where traffic separation is critical, and things happen quickly. During the en-route phase above 10,000 feet, there's much more time to switch to a backup and recover if interference occurs.

It will be interesting to see how the airlines implement this recommendation. That's all it is: a recommendation. The aircraft operator is still responsible for making sure that electronic devices do not interfere with the aircraft system, and ultimately that decision (and responsibility for the outcome) belongs to the pilot-in-command.

r81984
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Re: What a shocker!

Yes GPS signal is weak, but if it works at ground level with the entire cities work of radio signals then it will work at altitude with only 100 or so wifi or cell phones turned on.
Also the GPS antenna on an aircraft is pointed upward and is on top of the aircraft so it is not even seeing anything coming from the cabin.
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Silver_2000
Premium
join:2005-12-12
Carrollton, TX

its about attention

its about attention
they want your attention during take off and landing