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Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

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71–80 of 130 posts

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#71

This is strictly anecdotal evidence, but I'll throw in my 2 cents here. I have a private pilot certificate and am working toward an instrument rating right now, which involves being in continuous contact with air traffic control, flying in low / zero visibility conditions, and relying on aircraft instruments to guide me on landings. On numerous(if not all), I've had my iPhone with me, switched on and even in my lap a…

I've had my cell phone on during a commercial flight before. I had it off on the first leg, turned in on to call my wife during a layover, then forgotten I had done so when they asked me to turn the cell phones off on the second leg because mentally it still was off.

Given the number of flights I have been on (not all that many) and assuming I'm not particularly more or less likely to have this happen than anybody else (I'm feeling comfortably average here), and given the number of cell phones on a flight, I rather suspect that the average commercial flight of a big plane has at least one cell phone on for the duration with probability approaching 1.

Make of that what you will. My point is mostly that the odds that this debate are entirely academic and in fact flights routinely fly with cell phones on are in fact very good.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#72
post #68
post #65

Here is the reason straight from the FAA: "There are still unknowns about the radio signals that portable electronic devices (PEDs) and cell phones give off. These signals, especially in large quantities and emitted over a long time, may unintentionally affect aircraft communications, navigation, flight control and electronic equipment." http://www.faa.gov/news/fact_sheets/news_story.cfm?newsid=62... ie. We don't kno…

How hard could it be to get 500 phones, put them in a plane and dial them all ?

If there's 0.000000001% of anything happen, why risk?

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#73
post #7

I find it hard to believe that a plane's avionics are sufficiently shielded to withstand a direct lightning strike, but one person's phone will crash the plane. I've heard other explanations, too, such as the fact that too many mobile towers are line-of-sight at the same time, and the effective ground speed means you'd hop towers far too often and it'd mess with the phone system. Multiplied times the number of mobile…

The threat isn't about damaging the plane or forcing it to crash, it is about potential interference with electronic guidance and instruments, especially in the event of an instrument landing.

With a 2 degree glide slope during landing, even a 0.05% change in the radio signal can see a plane hit a mountain as opposed to safely clearing it. Here are two relevant accidents where the instruments were just a fraction off and caused a collision:

http://en.wikipedia.org/wiki/Korean_Air_Flight_801

http://en.wikipedia.org/wiki/Air_Inter_Flight_148

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#74
post #62

The plural of anecdote is not data, but stories are fun. Last Christmas, I was on a multi-hop flight back to SF from the east coast. We were going to be landing in Vegas, and I was talking to a flight attendant. She mentions that conditions in Vegas were a little crazy, as the runway doesn't drain properly and crosswinds are common. As we're preparing to land, the captain gives the usual speech. It's going to be a li…

Did it turn out that anyone actually had his phone on?

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#75
post #72
post #68

Earlier quoted context omitted.

How hard could it be to get 500 phones, put them in a plane and dial them all ?

If there's 0.000000001% of anything happen, why risk?

Because you have to live your life? The risk of getting killed in a car accident on the way to work is probably higher than that.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#76
post #48

Earlier quoted context omitted.

They take bottles of water or cans of coke off you because you might be able to crash a plane with one. They don't take your mobile phone off you, ergo they can't be that dangerous.

Your unspoken premise is that the FAA 1) Cares about safety (more than they care about appearing to care), and 2) That they know what they're doing.

If you want to be cynical about it, then the FAA also wants to stay out of the public eye any way possible, so it has less paperwork, less scrutiny, and less overhead to deal with.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#77
Former avionics tech here. Not scientific, but I've seen CDMA devices interfere with nav equipment, and GSM devices interfere with communications system (ala the infamous dat-dit-dah GSM sound over speakers). And these on nuke-hardened (EMP-shielded) military systems.

These issues aren't going to crash the plane, however with the sheer variety of cellular devices, it's just a good idea to keep them off.

Besides, you people who can't seem to shut them off are an annoying lot, so there's also a co-passenger sanity aspect to it. Just leave them off, are you that addicted to Farmville?

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#78

Earlier quoted context omitted.

That is a foolish conclusion. Firstly, if the TSA searches your bags and actually finds a "bunch" of cell phones, I bet that they will find an excuse to hassle you about it. Secondly, your own example shows how shoddy this reasoning is; the TSA is not rational* about what they confiscate and what they don't -- your water isn't dangerous, and they took it, so why would you trust their judgment on cell phones? Thirdly,…

it's (vaguely, remotely) possible that some new phone released yesterday is dangerous, That's no greater a possibility than for my netbook, or my wristwatch, for that matter. Why pick on phones over other electronics? (I suppose the answer is to see your previous paragraph regarding rationality)

They don't pick on phones over other electronics. On every flight I've been on, they ask passengers to shut off "all portable electronic devices," including things that often don't even communicate over a network, like CD players.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#79
post #48

Earlier quoted context omitted.

They take bottles of water or cans of coke off you because you might be able to crash a plane with one. They don't take your mobile phone off you, ergo they can't be that dangerous.

Your unspoken premise is that the FAA 1) Cares about safety (more than they care about appearing to care), and 2) That they know what they're doing.

If you don't feel safe enough flying in US under FAA you can try some more liberal on safety places like Africa or Indonesia. Your survival chances decline can be calculated quite precisely though.

Re: Ask HN: Are mobile phones on a plane taking off or landing really dangerous?

#80

Earlier quoted context omitted.

I flew a plane for the first time yesterday, it was only a tiny two seater, but with modern electronics. My instructor was using his iPhone during the flight and he didn't seem worried.

Flying a C172 G1000 is not the same as flying a 737-600. You're not shooting RNAV approaches, CAT I ILS, or low alt routes. You shouldn't even be looking at the instruments (I'm sure the CFI has told you). How about that annoying click/buzz in your headset from the phones TX? It's easy for you to ask your friend/CFI/passenger to turn off their phone but how about a cabin of ~100 people...while flying your approach?

Exactly -- big difference between a 2-seater flying VFR vs. IFR conditions.
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