Many fliers refuse to turn off electronic gadgets

Dec 23, 2011 By Gary Stoller

Gadget-dependent fliers are turning a deaf ear to flight attendants' instructions to turn off their devices during takeoff and landing, despite decades of government warnings, a USA TODAY investigation shows.

The investigation, which reviewed thousands of pages of technical documents and surveyed hundreds of frequent fliers, also confirms that the worry about electronics on planes is not baseless: The devices emit that can interfere with cockpit instruments and systems.

"We really need to get the technical findings out to the public and tell them it's dangerous to use their portable electronic devices in-flight," says Bill Strauss, an electrical engineer whose doctoral thesis at Carnegie Mellon University studied use of electronic devices in-flight.

Documents reviewed by USA TODAY include: more than 25 papers by electronics experts; presentations, papers and advisories by government aviation officials in the USA, Canada, the United Kingdom and Europe; congressional testimony; and Boeing research and information for airlines. The investigation also included: a review of government accident reports and airline pilots' incident reports; a survey of more than 900 frequent fliers; and interviews with Boeing, NASA and independent electromagnetic interference (EMI) experts, flight attendants and pilots unions, and college electrical engineering professors.

Fortunately for air travelers, the probability of EMI is small, the technical papers say.

EMI has not been cited as the cause of any fatal U.S. airline accident, but pilots have reported incidents in which they suspected EMI caused cockpit instruments to go haywire.

Some electronics experts - including Douglas Hughes, an electrical engineer who worked for McDonnell Douglas and the Department of Defense- suspect it might have caused military aircraft accidents and been an undetected factor in some airline crashes.

Goverment accident investigators in New Zealand said a pilot used a cellphone in the cockpit before he and seven passengers were killed on a charter flight in 2003.

The New Zealand Transport Accident Investigation Commission said the accident was probably caused by the pilot becoming distracted from monitoring altitude during landing. They noted in the accident report that cellphone use can cause "random interference to the proper functioning of aircraft avionics such as navigation equipment and autopilots."

Two recent events have caused frequent fliers to question why they're required to shut off their devices in flight.

On Dec. 6, actor Alec Baldwin was removed from an American Airlines plane for playing a game on his cellphone after a flight attendant told him to turn it off. On Dec. 1, the FAA gave approval to American's pilots - after months of tests - to use electronic tablets in cockpits.

American's pilots can use their own iPads any time during a flight to access aircraft and flight crew operating manuals and navigational charts, says the airline's spokeswoman, Andrea Huguely. The device's Wi-Fi must be turned off.

Pilots' iPad use "involves a significantly different scenario for potential interference than unlimited passenger use, which could involve dozens or even hundreds of devices at the same time," the FAA says.

Why fliers really do need to turn off electronic devices

"What part of 'please turn your cellphone off' do you feel does not apply to you?" Peter Juhren asked a fellow passenger as their New York-bound Delta Air Lines flight taxied for takeoff Dec. 7 at Tampa's airport.

Juhren, a frequent business traveler from Salem, Ore., says the woman on the phone gave "a disgruntled look" but stopped talking and turned it off - after three times ignoring a flight attendant's request to do so.

Passengers have blamed airlines and the government for safety problems for decades, but now they might have to share some blame.

A USA TODAY investigation shows that passengers are frequently disregarding flight attendants' instructions to turn off portable electronic devices during takeoff and landing - two critical flight phases when a mistake by a pilot could lead to an accident.

Many passengers question the rationale behind shutting off electronic devices in-flight, but the investigation's review of thousands of pages of technical documents shows the gadgets emit radio signals that can interfere with cockpit instruments and electronic equipment and systems on an aircraft.

"Any device with a battery - including cellphones, e-readers, laptops, PDAs (personal digital assistants) and Game Boys - has some level of emission that has the potential to interfere with cockpit instruments or navigational equipment," says Boeing engineer Dave Carson.

Technical committees have evaluated many portable electronic devices and found the margin of safety is not sufficient to allow passengers to use them during takeoff and landing, says Carson, co-chairman of an RTCA committee that studied portable electronic devices on aircraft.

RTCA is a non-profit corporation that develops communications and navigation recommendations for the Federal Aviation Administration.

Carson says most devices used "in aggregate or independently" by passengers would not meet the RTCA's DO-160 standard, which sets emission standards for airborne equipment.

Electronics experts say they do not have such electromagnetic interference (EMI) concerns about an increasing number of Wi-Fi and entertainment systems installed by aircraft manufacturers and airlines, because those systems are thoroughly tested to meet standards.

EMI-related documents reviewed by USA TODAY include more than 25 papers by electronics experts; presentations, papers and advisories by government aviation officials in the USA, Canada, the United Kingdom and Europe; congressional testimony; and Boeing research and information for airlines.

Some findings:

-A 2008 RTCA study, considered the most recent definitive one on the subject, confirmed that spurious emissions from transmitting portable electronic devices onboard aircraft "could exceed interference thresholds for critical aircraft systems."

RTCA, which gave USA TODAY permission to access the study, says an aircraft's localizer and glide-slope systems - two systems used for landing - "show potential susceptibility to continuous wave interference," supporting the "prohibition on the use of portable electronic devices below 10,000 feet."

The operation of portable electronic devices "changes the electromagnetic environment" of aircraft radio receivers and "may introduce additional interference effects."

-A 2006 FAA study of 38 flights operated by two airlines observed that cellphone calls were made during all flight phases, and other wireless devices were used during landing approach "well after" flight crew instructions to shut them off.

The study said "considerable onboard radio frequency activity" from cellphones was observed, including some that could interfere with aircraft GPS equipment.

-In a March 2001 service letter to airlines, Boeing said it received "various reports of anomalies in airplane communication and navigation systems that operators suspected were caused by interference from passenger carry-on electronic devices."

Boeing said it sometimes acquired the suspected electronic device but couldn't repeat the anomaly in a lab or on an airplane.

USA TODAY's analysis of NASA's Aviation Safety Reporting System, which lets airline employees report incidents confidentially, reveals that pilots and an air traffic controller reported 32 incidents of electronic device interference with aircraft systems from January 2001 through Dec. 2, 2011.

A pilot of a Canadair CRJ-200 regional jet reported compass system malfunctions after takeoff at an altitude of about 9,000 feet on a flight last May. The pilot says a passenger had an iPhone in standby mode; when the phone was turned off, the compass system operated properly.

A pilot of a Boeing 737 jet noticed that navigational radios were not updating after takeoff from San Francisco airport in August 2007. The radios started to update after a passenger shut off a handheld GPS.

USA TODAY surveyed more than 900 frequent fliers and asked them, among other questions, how often fellow passengers disregard flight announcements to shut off electronic devices.

Nearly half of 133 frequent fliers who responded to the question said they see fellow passengers disregarding the announcements on every flight or nearly every flight. More than three-quarters of respondents said they often, or always, see such disregard.

Frequent fliers report various tactics fellow passengers use to operate their electronic devices after being told to shut them off. Among others, they turn devices over so the screens aren't visible, and they operate the gadgets under blankets or after flight attendants sit down for takeoff or landing.

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Cave_Man
2.7 / 5 (12) Dec 23, 2011
They'll shut off their damn phones when the plane starts to nosedive. If only I we're a pilot, oh the fun I would have...

"This is your captain speaking: I would like to personally thank the jerk who wanted to play their gameboy during takeoff. Once again this is your Captain, enjoy the remaining 15 seconds of your flight and I'll see you all in hell" *screams*
Amy_Steri
5 / 5 (4) Dec 23, 2011
"Boeing said it sometimes acquired the suspected electronic device but couldn't repeat the anomaly in a lab or on an airplane."
Kafpauzo
3 / 5 (8) Dec 24, 2011
Prosecute them for putting people's lives in danger. Putting people's lives in danger is definitely punishable by law.

It's not up to the perpetrator to opine whether he's endangering people or not. The perpetrator's opinions are immaterial. The law is quite clear. If it can be shown that you're endangering people's life, with experts confirming it, then you can and should be punished.

In addition to this, airlines should also ground the perpetrators for five years, and should file civil lawsuits for compensation for the costs of traffic delays caused while trying to get these people to finally comply, or in the end leading them off the plane. Such delays can sometimes become amazingly expensive for the airlines, due to tight traffic planning that makes disturbances propagate all over the map.

There's really no excuse for endangering people's lives, just for a few minutes of entertanment.

This is what the law is for. When people refuse to behave, the law is there to make them.
TheSpiceIsLife
3 / 5 (6) Dec 24, 2011
Given that a handful of large flight companies are now allowing business class passengers to connect to the Internet via an inflight wifi access point, we should expect to see an increase of inflight instrument malfunction, right?

Take off and landing are critical periods of a flight, but they shouldn't be the only windows where instrument malfunction due to passenger gadget EMI occurs.
Kafpauzo
2.7 / 5 (7) Dec 24, 2011
Given that a handful of large flight companies are now allowing business class passengers to connect to the Internet via an inflight wifi access point, we should expect to see an increase of inflight instrument malfunction, right?


I suggest that you try reading the article. If you just read the article, you'll find out why this objection doesn't apply.

Take off and landing are critical periods of a flight, but they shouldn't be the only windows where instrument malfunction due to passenger gadget EMI occurs.


For this, too, you might consider reading the article. You'll find the answer to this point too.

Actually, whenever you want to comment on an article, it's always a good idea to read it before you comment on it. This way your comments will give a much better impression.
henryjfry
3.2 / 5 (11) Dec 24, 2011
Why? Because many fliers refuse to believe an electronic gadget will have any affect whatsoever on a plane.
And if it possibly does, shield the equipment. Problem solved. These are not military planes, they are commercial vehicles which we pay to use. We all have phones and other electronic gadgets. It would be impossible for airlines to force people to comply anyway so if this is an actual, real, not made up or possibly outdated risk, they are just going to have to shield their equipment. Surely turning the cockpit into a Faraday cage is not impossible.
Fair enough people can turn devices off but if it is such a risk do you really want to tell people that they will only be safe if they actually remember to turn their stuff off and the airlines are going to take no further action to protect you. That is sheer lunacy, which is why i never believe them when im on a plane and leave my stuff on in my pocket out of spite.
Kafpauzo
3.1 / 5 (9) Dec 24, 2011
henryjfry, in a modern aircraft there's an enormous amount of wiring and electronics that would need to be shielded. The weight of the aircraft would increase quite dramatically. This means that airplane tickets would become much more expensive.

Is it really such a terrible suffering to abstain for just the very few minutes during takeoff and landing?
Kafpauzo
2.3 / 5 (6) Dec 24, 2011
henryjfry, what's your theory about these rules? Do you think that airlines create rules because they want to annoy their customers? Do you think they are children who laugh as they trick people into complying? What's your theory?

Seeing that there are people who will put their own and other people's lives in danger because of something as trivial as a childish demonstration of spite, apparently the airlines need to provide every aircraft with a tracking detector that pinpoints the location of each device.

"This is your captain speaking. Will the passenger in seat 27E please turn off your cellphone? We are not allowed to take off until you turn off your phone."
kaasinees
1.6 / 5 (7) Dec 24, 2011
Dont forget that with modern smartphones you can turn it into a wifi router gone hyper, it will increase electronic errors for certainly. A terrorist could turn the smartphone into a plane hijacking device.
At the university a year ago they jammed the wifi network by doing this. 5 or so kids turning their phones into small jamming devices by abusing their wifi functionality, probably running custom android ROMS.
We had to get security to tell them to piss of, and had to use wifi scanners to tell where they were.
Doug_Huffman
2.1 / 5 (11) Dec 24, 2011
Instructions from an un-credible instructor have the opposite effect of that desired. 'Converging and diverging views', Section 5.3, pp 126 - 132, Probability Theory: The Logic of Science, E. T.Jaynes. Who fails to do arithmetic is doomed.
Bob_Kob
4.4 / 5 (7) Dec 24, 2011
henryjfry, in a modern aircraft there's an enormous amount of wiring and electronics that would need to be shielded. The weight of the aircraft would increase quite dramatically. This means that airplane tickets would become much more expensive.


God forbid any sort of EMI created from the environment at magnitudes greater of power than that emitted from small mobile phones.. oh I don't know, thunder storms, solar flares etc etc?

Point being if these aircraft are so susceptible to the slightest bit of interference, then maybe they shouldn't be in the air...
GuruShabu
2.3 / 5 (8) Dec 24, 2011
henryjfry, in a modern aircraft there's an enormous amount of wiring and electronics that would need to be shielded. The weight of the aircraft would increase quite dramatically. This means that airplane tickets would become much more expensive.


God forbid any sort of EMI created from the environment at magnitudes greater of power than that emitted from small mobile phones.. oh I don't know, thunder storms, solar flares etc etc?

Point being if these aircraft are so susceptible to the slightest bit of interference, then maybe
they shouldn't be in the air...

You are absolutely right!
These rules are a reminiscence from the 9/11 and presently they have no facts to substantiate them. That's the simple reason people couldn't care about a e_reader can crash and 777.
If if can, we better not fly them because any terrorist in the world can afford a much powerful electronic device to do the job.
henryjfry
4.6 / 5 (5) Dec 25, 2011
Exactly, its so easy not to turn your devices off that if this were actually true planes should be dropping out of the sky all the time. Short of them waving some sort of wand over every single passenger before takeoff there is absolutely no way to make sure people turn their stuff off. Therefore if there actually is any sort of risk from consumer electronics to a plane merely asking people to turn their stuff off is actually doing nothing to mitigate that risk. If there actually was any sort of serious risk from this they wouldn't let people have that stuff on the plane. Or they should build the planes so they are not susceptible.
Either way just asking people to turn their stuff off is not the way to approach a supposed safety risk.
henryjfry
4.2 / 5 (5) Dec 25, 2011
"henryjfry, what's your theory about these rules? Do you think that airlines create rules because they want to annoy their customers? Do you think they are children who laugh as they trick people into complying? What's your theory?"
Because I don't believe that's its actually true (anymore) I believe that this may have been true with older planes, possibly the first general commercial airplanes. However with the prevalence of consumer electronics there is no way this could possibly be true anymore (or terrorists would be dropping planes with smartphones, not trying to blow them up) so i think its now just part of the general sphiel they spew at passengers. Possibly to get people to pay attention to the air waitress.
Kafpauzo
2.6 / 5 (5) Dec 25, 2011
God forbid any sort of EMI created from the environment at magnitudes greater of power than that emitted from small mobile phones.. oh I don't know, thunder storms, solar flares etc etc?


If a thunderstorm disturbs radio communication with a few crackling noises, the pilot can reply "please repeat" and hear the message again. If instead the same communication is disturbed by a continuous buzz as 50 passenger cellphones connect to new cell towers -- with this buzz randomly distributed over time, due to differences in each cellphone's signal strength -- then the pilot is still very likely to succeed in getting the message. But some unlucky day this will coincide with some other difficulty, and he won't get the message.

That's not intended as an accurate description of the exact interference, but I think it makes the principles easy to understand.

What makes you think that you are more qualified to judge electronic interference than the people behind those 25 expert papers?
Kafpauzo
2.6 / 5 (5) Dec 25, 2011
If there actually was any sort of serious risk from this they wouldn't let people have that stuff on the plane.


Clearly they have assumed that a sufficient percentage of people are sufficiently grown-up and responsible to turn off their gadgets. If this assumption is wrong, I think they'll probably have to install tracking detectors, and until the detectors are installed, they'll have to do exactly what you say, and forbid all such gadgets entirely
Kafpauzo
2.4 / 5 (5) Dec 25, 2011
(or terrorists would be dropping planes with smartphones, not trying to blow them up)


It's not a simple on-or-off thing. It's not that you can easily overwhelm the machinery. Safety margins are high. Even with a lot of disturbances, it's very likely that everything will work out fine, and no problem will arise. But one day there'll be sufficiently intensive and persistent disturbances of different kinds to trig a cascade of problems.

By your reasoning, the pilots could just as well work while drunk. Any skilled pilot can do his job well while drunk, as long as everything follows routine and there are no major crises. And aircraft could have a lot more material fatigue than what is actually allowed. The likelihood of breakage would still be small.

so i think its now just part of the general sphiel they spew at passengers. Possibly to get people to pay attention to the air waitress.


World-wide conspiracies that lie about secret motives are impossible to maintain.
ahmedgnz
4 / 5 (5) Dec 25, 2011
E-readers like the Kindle (with the exception of the Fire) use e-paper technology that consumes power only when the page changes. If the WiFi function is turned off, the device consumes less power than a hand watch and should therefore have less interference potential than the watches almost all passengers wear. The anecdotal data this article presents seems to imply that the interference problem lies mostly with the WiFi capabilities of these devices. At any rate, FAA regulations state that airlines should conduct scientific (not anecdotal) studies on whether or not and how electronic devices may interfere with flight instrumentation and thus advise the FAA which, if any, may be safe to operate so that the agency revises its rules accordingly. Except for the recent study on the use of its own (WiFi-less) PDAs the iPad to access flight manual info, no airline has ever conducted such scientific studies on passenger held devices.
dbsi
3.5 / 5 (2) Dec 25, 2011
Either this is stupid or reckless implementation of aviation technology or stupid policy implementation. As mentioned above, not preventing malicious use of electronic gadgets. The phones would need to be scanned for bad aps for that matter or the lithium ion batteries would have to be removed and be dropped in to the bin together with the knives as they are by far the most dangerous parts regularly taken in toa plane.
MorituriMax
2.3 / 5 (3) Dec 25, 2011
despite decades of government warnings,
...more like decades of hype. I'll take their word for it after I see some rigorous test data. Are the pilots turning off THEIR ipads?

Pilots' iPad use "involves a significantly different scenario for potential interference than unlimited passenger use, which could involve dozens or even hundreds of devices at the same time," the FAA says.
Of course it's different. They don't want to follow the rules if it affects THEM.
MorituriMax
4 / 5 (4) Dec 25, 2011
Maybe we should wonder why companies produce airplanes that are this susceptible to interference? Sure, lets get on the passengers case, but the actual offenders are the builders and the FAA for not forcing them to adhere to more stringent rules for insulating the aircraft systems in question?

Couldn't one of these voodoo mysterious factors be things like solar activity or other natural effects that are much stronger than cell phones or other gadgets? Perhaps the crew shouldn't be as wary of the aircraft interphone system that is wired all through the aircraft? Oh, wait, that would inconvenience the CREW!

kafpauzo spurted,
Prosecute them for putting people's lives in danger.
Well, don't you think it would be a good thing to actually have evidence that they are doing this, instead of unsubstantiated hearsay that "it might do bad things?"
MorituriMax
4 / 5 (4) Dec 25, 2011
kafpauzo spurted again,
Clearly they have assumed that a sufficient percentage of people are sufficiently grown-up and responsible to turn off their gadgets.
Are you an idiot or do you just play one on the internet? The point is that people carry them around and are so used to carrying them that they MAY NOT REMEMBER to disable, remove the battery, power down, or whatever else is required to make sure the plane doesn't crash into the ground from 50,000 feet due to a spike in twitter messages.
Kafpauzo
2 / 5 (4) Dec 25, 2011
kafpauzo spurted,
Prosecute them for putting people's lives in danger.
Well, don't you think it would be a good thing to actually have evidence that they are doing this, instead of unsubstantiated hearsay that "it might do bad things?"


Yes, of course. Let's wait until we've had a sufficient number of crashes where it can be proven without a shred of a doubt that one of the transistors on one of the chips in the burned wreckage got bad signals before the crash, and that the only possible cause of this was passenger electronics, and that the transistor's bad signal was the only possible cause of the crash.

No problem for me. I hardly ever fly. If so many fliers are willing to die until their death has provided solidly incontrovertible proof, fine, let them. It's their choice.

The point is that people carry them around and are so used to carrying them that they MAY NOT REMEMBER


Indeed, some people are dense enough to forget no matter how clear the reminders are.
Grizzled
3 / 5 (2) Dec 25, 2011
Will they ask the passengers to switch off their heart pacers too? Other medical electronic devices? Those are battery operated too. Some have radio frequency up/down links.
Grizzled
3 / 5 (2) Dec 25, 2011
And speaking of radio frequencies... How come a cheap transistor radio has no difficulty tuning to one station and out of all others while a sophisticated multi-billion dollar system like a passenger jet can't?

Surely cellphones and such operate in different frequency ranges compared to the aviation electronics, use different comms protocols. As others have pointed out - if it is indeed possible to bring a plane down by forgetting/neglecting to switch your device off - or dear, we better never fly at all. It's clearly so fragile and unreliable.
Skepticus
2.3 / 5 (3) Dec 26, 2011
The fact that passengers had ignored these "interferences" doom and gloom advise for years without planes dropping out of the sky show that the risk is close to nonexistent. But hey, 9/11 mentality dictates that they have to try to blanket-ban the lot of passengers' electronics, just in case some clever terrorist really found a way to crash a plane with personal electronic gadgets. I imagine those who cooked up these proposed ban regularly throw out their soups and salads at home, because of the off chance they missed a worm, bug or two?
GuruShabu
2.2 / 5 (5) Dec 26, 2011
Thus is all a big pile of crap. Qantas and Singapore airlines are launching full Internet access for business and first classe. Full iPad and iPhones.
Stop dreaming about fallacies.
Kafpauzo
3.7 / 5 (3) Dec 26, 2011
Thus is all a big pile of crap. Qantas and Singapore airlines are launching full Internet access for business and first classe. Full iPad and iPhones.
Stop dreaming about fallacies.


During takeoff and landing? The article is about takeoff and landing.

Cellphones become possible if you install a cell tower in the plane, and meet other requirements. Then you no longer have 100 phones switching towers at machine-gun frequency. During switching they "yell" for new towers, very "loudly" when all towers are far away, so the radio spectrum gets very noisy. Without that, the phones are far calmer.

But hey, let's pretend reality is dead simple. Let's pretend it's as simple as a fairy tale! As with fairies, if you close your eyes and pretend hard enough, maybe it becomes true.

Anyway, Grizzled has solved the problem. He knows how to tune the susceptibility of all the electronics in an entire plane to one and the same radio frequency. Now there's a guaranteed Nobel prize in physics.
Grizzled
1 / 5 (2) Dec 26, 2011
Poor Kafpauzo. He/she/it clearly doesn't understand the difference between a frequency and a frequency range. Yet, for some reason presumes to offer their opinions.
Kafpauzo
5 / 5 (1) Dec 26, 2011
How come a cheap transistor radio has no difficulty tuning to one station and out of all others while a sophisticated multi-billion dollar system like a passenger jet can't?
Surely cellphones and such operate in different frequency ranges compared to the aviation electronics, use different comms protocols.


He/she/it clearly doesn't understand the difference between a frequency and a frequency range.


It's not a matter of radio tuning. If it were that simple, indeed it would suffice that it "operate in different frequency ranges" and "use different comms protocols".

The problem is different. Every electronic circuit is to some extent an inductor. Gadgets can therefore induce very tiny, random currents anywhere in the plane's entire curcuitry, not just in radios. The frequencies involved are highly random, and induction anywhere will propagate, so to protect by frequency tuning you'd have to tune all circuits to one extremely narrow frequency band, i.e. one frequency.
antialias_physorg
3 / 5 (4) Dec 26, 2011
God forbid any sort of EMI created from the environment at magnitudes greater of power than that emitted from small mobile phones..

We need to make a distinction between analog EM and digital EM disturbance. The noise signature is quite different. Digital circuits are very vulnerable to digital signals, but are quite immune to analog signals many orders of magnitude greater (e.g. solar storms or even thunderstorms)

The thing which induces a signal is the dE/dt (Eneregy change over time). With steep flanks from digital devices (especially mobile phones) this value is quite large - even though the wattage is very low.
Quarl
4.5 / 5 (2) Dec 26, 2011
I wonder about this rule only because it should be much cheaper to put 100 iPhones in luggage and simply do experiments rather than smuggle C-4 or RDX or Semtex or whatever the explosive flavor of the month is into luggage. If these devices are as dangerous as we are told then those that want to make aircraft fall should be able to figure out the proper conditions pretty quickly.

I suspect that most people feel that if their electronic pacifiers can be used during flight then take off and landing should be no different. If these devices are really that dangerous all airlines need to do is simply make customers put WiFi devices with their shampoo, toothpaste and nail files...in the luggage compartment. Then they can force customers to use their flight-safe internal WiFi. That'd go over real well.
antialias_physorg
3 / 5 (4) Dec 27, 2011
If these devices are really that dangerous

The devices aren't dangerous per se. The problem is that they work on a number of different frequencies with different bit rates and you can't just test all your electronics and wiring on board a plane whether they are susceptible to EM radiation from all old (and newly available) gadgets.

Without such tests the behavior is just undefined and unknown. That in itself isn't a problem in many other circumstances - but on an airplane (or in medical settings) 'undefined/unknown behavior' is an unacceptable risk.
Kafpauzo
3.7 / 5 (3) Dec 27, 2011
Quarl, filling a suitcase with phones would be an extremely inefficient way to cause crashes. You'd have to put a suitcase on every plane for years and years. Then, maybe once every five years or so it might cause a crash.

It's a matter of random chance. As random as winning the lottery or rolling dice. The outcome is unpredictable and the risk is quite small.

Imagine that someone invites you to a game. He says you'll roll dice a few times. If your result is a one on every throw, you lose. If it's anything else, you win a prize.

Great odds, right?

The prize if you win is that you get to play Tetris for a few minutes. That's all you can win. If you lose, the guy shoots you dead.

Would you accept this game? This is almost exactly what people insist on when they refuse to turn off their gadgets. Only once every five years or so it will cause a crash somewhere. But then everyone may get killed.

The airlines think that this carnage every five years is unnecessary and unacceptable.
Kafpauzo
5 / 5 (1) Dec 27, 2011
I'm astonished and stunned that so many people accept these risks so willingly. Usually the reaction to risk is the exact opposite.

After Fukushima, Germany is ending all nuclear power, because of perceived risk. This inevitably leads to more coal and pollution (including more radioactivity, ironically). But the risks from nuclear power are ridiculously small. Compared to this, the risk to each traveling passenger from unsuitable in-flight gadgets is orders of magnitude larger.

It gets even weirder if you consider the reactions of the US to terrorism. The risks from terrorism to any individual is infinitesimal. And yet, the US sacrifices essential liberty and citizen privacy, along with incredible economic resources, just to fight this ridiculously tiny risk.

Thus, people are willing to sacrifice the planet's future and their own liberty in the face of vanishingly tiny risks. Yet they won't sacrifice a single minute of Tetris even in the face of substantial danger.
CHollman82
1.6 / 5 (12) Dec 27, 2011
These comments and ratings are quite confusing. The article mentions a guy with a PhD from Carnegie Melon who did his doctoral thesis on this topic and a bunch of halfwits on the internet seem to think they are more intelligent than he is and know better than he does in order to go against his findings and recommendations. You all sound like a bunch of damn babies who don't want to turn your video games and facebook machines off for five goddamn minutes.

Now, I agree that if this is such a risk the airlines should do more than just ask people to comply, they should force people to comply... kicking that Baldwin clown off the plane earlier this year was a good start.
antialias_physorg
2.8 / 5 (4) Dec 27, 2011
After Fukushima, Germany is ending all nuclear power, because of perceived risk.

We were poised to end nuclear anyways. Fukushima just accelerated that process.
This inevitably leads to more coal and pollution (including more radioactivity, ironically)

Nope. All (even the most conservative) projections show that by 2022 (when the last reactor goes off line) we'll have replaced the entire electricity production currently furnished by nuclear powerplants with energy from alternative power plants.

While your points on risk awareness and risk assessment are well made, you should base them on facts - not fiction.
Kafpauzo
4 / 5 (1) Dec 27, 2011
All (even the most conservative) projections show that by 2022 (when the last reactor goes off line) we'll have replaced the entire electricity production currently furnished by nuclear powerplants with energy from alternative power plants.


If this turns out to be true, then congratulations to you! So far I've never seen any convincing hard facts that show this to be possible, and far too many that say it's impossible.

But I'd be absolutely delighted to be wrong on this point! The planet certainly needs good solutions!

While your points on risk awareness and risk assessment are well made, you should base them on facts - not fiction.


No fiction intended. But I must base what I say on the facts that I have seen.

Although I remain unconvinced, I do have room for some hope. So let's hope that the facts and conclusions that I've seen are wrong!
antialias_physorg
3 / 5 (4) Dec 27, 2011
So far I've never seen any convincing hard facts that show this to be possible,

Well, as of 2011 we're at 19% electricity from alternative sources (the most optimistic projections by the Green party for 2011 predicted only 17%). This bodes well for future development. Fukushima certainly gave it another boost in terms of investments.
And that boost hasn't even shown up yet in the numbers, since investment is, of course, always a few years ahead of connecting stuff to the grid.

I'm pretty optimistic that this green revolution will continue. Given that the total amount of subsidies to get to this point have been only one seventh of the subsidies to nuclear for roughly the same output. It's a massively good deal.

(Nuclear supplies 22% of electricity - and has gotten nearly 200bn Euros in subsidies, whereas alternative sources hav gotten less than 30bn to date and are already suplying 19%)

(Coal currently supplies the rest - but has also received 200bn over the years.)
Kafpauzo
4.5 / 5 (2) Dec 27, 2011
Antialias, that sounds great.

Unfortunately, it seems statistics like these are often warped by sloppy accounting. For instance, if you use oil-based fertilizers for energy plants, this is a dependency on oil, and the amount of oil dependency should be shown in the accounting, in reliable, hard numbers. And if a solar-panel factory is highly polluting, or consumes very rare elements, again this should be shown in the accounting with hard numbers. Only then can you quantify to what extent the energy plants, factories etc. are actually sustainable in the long run.

I'm of the impression that all too often this accounting is done quite wrong.

But the subject is complicated enough that you can't always say if one way of accounting is better than another. For instance, unsustainable dependencies on rare elements will sometimes vanish with new discoveries.

Humanity is still learning these things. The steady progress that you describe certainly sounds encouraging.
Kafpauzo
3.4 / 5 (5) Dec 27, 2011
These comments and ratings are quite confusing.


I've found that comment ratings on PhysOrg can become so strange that sometimes you just have to ignore them.

On other sites you can learn useful things from the ratings on your comments. I often get hints and clues that help me improve my debating skills. Here, very often I can't learn anything at all from the ratings. Polite comments that give helpful facts and very careful reasonings can sometimes get a 1. I've even seen some comments with only childish outbursts and no actual content getting a 5. It's just weird and meaningless.

And this is rather unfortunate, because there are some debaters on this site who could use a couple of hints and clues to hone their debating skills. It's too bad, then, that there are too many people destroying the usefulness of ratings, by giving ratings that you just can't interpret in any meaningful way.
CHollman82
1.4 / 5 (11) Dec 27, 2011
I've found that comment ratings on PhysOrg can become so strange that sometimes you just have to ignore them.

On other sites you can learn useful things from the ratings on your comments. I often get hints and clues that help me improve my debating skills. Here, very often I can't learn anything at all from the ratings. Polite comments that give helpful facts and very careful reasonings can sometimes get a 1. I've even seen some comments with only childish outbursts and no actual content getting a 5. It's just weird and meaningless.

And this is rather unfortunate, because there are some debaters on this site who could use a couple of hints and clues to hone their debating skills. It's too bad, then, that there are too many people destroying the usefulness of ratings, by giving ratings that you just can't interpret in any meaningful way.


Well I hope you don't take my 5 rating as an attempt to argue against your point :D
Kafpauzo
3 / 5 (2) Dec 27, 2011
Well I hope you don't take my 5 rating as an attempt to argue against your point :D


Thanks!

Wait... What? Are you saying that your 5 confirms my point? Your 5 confirms that ratings lack meaning? The meaning of your 5 is that your 5 lacks meaning? *Head starts spinning* :D
antialias_physorg
3.7 / 5 (3) Dec 27, 2011
And if a solar-panel factory is highly polluting, or consumes very rare elements, again this should be shown in the accounting with hard numbers. Only then can you quantify to what extent the energy plants, factories etc. are actually sustainable in the long run.

Photovoltaics do not seem the way to go (though I do see entire fields of these cropping up). Wind, biomass and solar-thermal have been the staples of the changeover - none of which require much in the way of exotic materials or are polluting to any extent)

Wind is already cheaper than nuclear per kWh. If you figure in all ancillary costs (waste disposal, teraing down nuclear reactors, ... ) then it is vastly cheaper. Solarthermal and biogas are not far behind.
Grizzled
1 / 5 (3) Dec 27, 2011
Sorry for responding a bit late but here goes:

It's not a matter of radio tuning. [..]
The problem is different. Every electronic circuit is to some extent an inductor.

*** So we are no longer talking about RF but induction currtents now? That's a very different kettle of fish.

Gadgets can therefore induce very tiny, random currents anywhere in the plane's entire curcuitry, not just in radios.

*** Just how tiny is tiny? There is a reason all modern comms devices use RF in one form or another and not induction currents. The reason is that those currents are pathetically weak even with a good-sized power source. With a cellphone battery and currents? Forget it.

The frequencies involved are highly random, and induction anywhere will propagate

*** Nope, it won't. Elementary diod decoupling takes care of such random currents. Please remember, those can be produced by anything. All the way down to your brain if it comes to that. Not to mention wristwatches and such.
antialias_physorg
5 / 5 (2) Dec 27, 2011
The magnitude of inductance is determined by the first derivative of current over time - not the magnitude of the current itself.

Signals from high bandwith digital devices have VERY steep flanks (hence: digital) - so even with small currents you get large induced coupling.
This is why your tiny phone, with almost no power to it, can be picked up by an amplifier station up to 2 kilometers away.

All it takes is a piece of wire with just the right length. At the frequencies most phones are using that length of wire is on the order of the stuff you find on integrated circuits - which are the backbone of all of a plane's electronics.
Kafpauzo
5 / 5 (1) Dec 28, 2011
What Antialias said. And:

So we are no longer talking about RF but induction currtents now? That's a very different kettle of fish.


Induction currents were the subject all the time. When you talked about "cheap transistor radio" and "different comms protocols" I thought you were intentionally derailing the discussion. It didn't occur to me that anyone could discuss this problem and not discuss induction.

Induction does happen at radio frequencies. An antenna is an RF-tuned inductor. And, as Antialias explains, the conductive traces in electronic circuits can act as (weak and unpredictable) antennas.

Digital chips in iPads etc. switch signals at GHz frequencies, which are UHF frequencies, so every digital circuit emits some RF and can pick up some RF. The signals are essentially square, meaning there are lots of overtones, lots of frequencies. The resulting noise is complicated enough that it's quite impossible to predict when and where a stray error will be induced. >>
Kafpauzo
5 / 5 (1) Dec 28, 2011
>> All you need is some very bad luck, and suddenly lots of iPads happen to switch at exactly the same time, jointly producing an induction current that changes a 1 to 0 somewhere in the plane.

induction anywhere will propagate
Elementary diod decoupling takes care of such random currents.


The 1000-character limit can make it difficult to explain well. I didn't explain very carefully here, since I found the whole idea of "different frequency ranges" ludicrous, and didn't think you were serious.

What happens here is that induction-caused errors will propagate. If an induction causes a switch from 1 to 0 somewhere, a receiving circuit somewhere will receive this bad information, and will therefore produce bad information, and this will propagate.

At cruising altitude there's some room for error. When you're landing, and are five seconds from the runway, you really, really don't want sudden, unexpected errors to pop up. Then the pilots must focus completely on landing.
Kafpauzo
not rated yet Dec 28, 2011
There is a reason all modern comms devices use RF in one form or another and not induction currents.


I can't extract any meaning from this sentence. Were your attempts to explain thwarted by the 1000-character limit?

Anyway, I suggest you check this page:

http://en.wikiped...requency

By the way, when you want to quote several portions of text in the same comment, note that when you click "quote" you get the quoted text between a bracketed q and a bracketed /q. The bracketed q marks the beginning of a quote, and the bracketed /q marks the end. You can use these markings any number of times in the same comment. Thus you can start every quoted portion of text with a bracketed q and end it with a bracketed /q.
Grizzled
1 / 5 (2) Dec 28, 2011
The magnitude of inductance is determined by the first derivative of current over time - not the magnitude of the current itself.

*** Are you sure? Let's try a thought experiment - reduce the original current by x10 - what happens to the inducted current x100? ?10^100? Still doesn't matter?

This is why your tiny phone, with almost no power to it, can be picked up by an amplifier station up to 2 kilometers away.

*** Are you telling me those stations pick up INDUCTED currents?!? Oh boy.

CHollman82
1 / 5 (9) Dec 28, 2011
By the way, when you want to quote several portions of text in the same comment, note that when you click "quote" you get the quoted text between a bracketed q and a bracketed /q. The bracketed q marks the beginning of a quote, and the bracketed /q marks the end. You can use these markings any number of times in the same comment. Thus you can start every quoted portion of text with a bracketed q and end it with a bracketed /q.


Grizzled, read this and do it please...
antialias_physorg
5 / 5 (3) Dec 28, 2011
Are you sure?

Yes. I'm sure. I have a university degree in electrical engineering. I had to study this crap (not my favorite part of the courses, I can tell you).

I have gone to labs with prototypes of devices to do the EMF testing.

And if you don't believe me then read the inductance page on wikipedia
http://en.wikiped...ductance

If that's too technical then here's the link on "How stuff works" for cell phones.
http://www.howstu...hone.htm
Kafpauzo
5 / 5 (1) Dec 28, 2011
I have a university degree in electrical engineering.


Sounds like I should be a bit careful about speaking so confidently about this subject. I only speak from what I remember from high school, combined with various facts that I've picked up here and there because I'm very interested in technology in general. And then I've spiced it all with a pinch of googling.

Grizzled, if Antialias and I should contradict each other, trust Antialias, not me. Although I'm fascinated by these things, and fascination certainly helps you learn quite a lot, it can't beat real schooling.
antialias_physorg
not rated yet Dec 28, 2011
As far as I can tell your explanations are correct.

The flipping of a single digit, however, will likely not have any effect. Planes have multiple redundant systems and secure encodings (parity checks, using hamming distances of 3 or more for the information sent, etc. so that error correction is possible). So the likelyhood is slim that a gadget will have any noticeable effect (beyond an error log entry). But compund effects could be dangerous. And I do think it's a small price to pay NOT to play angry birds for a couple of minutes during takeoff/landing if it means that one less plane falls out of the sky.
Bob_Kob
5 / 5 (1) Dec 29, 2011
Hey i'm a graduate electrical engineer as well,listen to me!!

Anyway before you guys kill eachother over the theory:-

*Consumer electronics aren't going anywhere soon.
*You cannot count on people intentionally or non intentionally turning off devices.

Therefore the ONLY solution to this is a SUITABLY designed electronics system. Almost every consumer device these days has the 'this device must not generate and must accept all forms of interference'.

To throw away safety for the means of cost cutting by forcing people to act or do a certain way is a joke. When we have inbuilt neural electronics in 40~ years are they going to tell us to turn that shit off?...

The joke is in the electrical engineers designing this, not the theory.
bluehigh
1.3 / 5 (12) Dec 29, 2011
Gotta go with Bob Kob.

@antialias - if you truly studied elec eng you would know that near and far field propagation of EMF are far more complex than just the magnetic component associated with inductance.

In any case its BS that a modern airplane with fibre optic fly by wire systems and hardened electronics is going to be affected by local RF emissions.

antialias_physorg
not rated yet Dec 29, 2011
In any case its BS that a modern airplane with fibre optic fly by wire systems and hardened electronics is going to be affected by local RF emissions.

We don't yet have 100% photonic chips. This means that (even with fibre optic connections) the actual processing parts are electronics.
It's electronic components/conductors that are on the order of (half) the wavelength of the EM radiation emitted which are a problem because they can serve as an antenna. For the some electronic devices that means wire lengths of a few centimeters down to millimeters and less (depending on overtones even less). The long lines in an airplane aren't a problem.

And no: Not all electronics on board planes are 'hardened' against noise from digital devices. Not even on the newest models. Not even all military planes are completely hardened. (and on older models no one had any idea that people would have such gadgets)
bluehigh
1 / 5 (9) Dec 29, 2011
I can only guess then that all those TV sets in the back of seats, the lighting systems with associated inverters, the intercom system, - don't have any wires. For some real noisy RF go use an electric razor in the washroom.

antialias_physorg
not rated yet Dec 29, 2011
And guess what: They're not turned on during takeoffs and landings, either.

Even if: these are electronics which are known. You can test whether they cause trouble during the entire development of the plane. ALL the eletronics on a plane have been extensively tested whether they cause interference with each other.

But you can't know what types of gadgets people will lug along (especially since most of these won't even have been invented while the plane is being developed). You can't go and put a plane in an EMF testchamber whenever Nokia puts out a new phone.
bluehigh
1 / 5 (9) Dec 29, 2011
As Bob Kob mentioned ... the FCC requires that RF devices are tested and certified not to interfere with other devices. Is it that airplane designers deliberately fail to provide shielding or error correction for the electronic systems? Perhaps restrict nylon clothing lest a static discharge emit a stray EM pulse.

No conclusive proof exists that a consumer device has ever caused a flight system to malfunction. No wonder passengers are skeptical. Just more paranoia and fear mongering.
Kafpauzo
not rated yet Dec 30, 2011
Bluehigh, they are certified not to interfere with everyday uses, like word processing and such. This does not extend to situations where people's lives depend on machines to work perfectly.

Visit any hospital. You'll see signs in several places asking people to turn off their cellphones. That's because people's lives depend on heart monitors etc.

If a word processor crashes once every five years, you lose text. You don't die from it. The certification means that word processors will only crash very, very rarely. Maybe once in five years, or something like that. That's OK for losing text. It's not OK for getting killed.

Because of this difference, there are differences in the requirements for everyday word processing and life-critical machines. The rules are different. The quality assurance is different. Everything is different. You can't demand that they must be the same.

When an aircraft is landing, everyone's life depends on the machinery. This is different from word processing.
Kafpauzo
not rated yet Dec 30, 2011
Antialias, thanks for confirming that I got things right. It's nice to see that my efforts to get my explanations right were successful.

I didn't really expect that a single-bit flip would be likely to cause anything major. But since the audience here refuses even the most extremely simple and clear explanations, I thought I'd simplify this as far as I ever could. Otherwise one enters the field where even redundancy isn't totally infallible, as with the compound effects that you mention. I thought that maybe if I kept it as extremely simple as I ever could, maybe the explanation would be clear enough.

Clearly I was too optimistic. But I've always been an optimist...
Kafpauzo
1 / 5 (1) Dec 30, 2011
Is it that airplane designers deliberately fail to provide shielding or error correction for the electronic systems?


God is supposed to be infallible. We are not yet able to create airplane electronics that are like God.

No conclusive proof exists that a consumer device has ever caused a flight system to malfunction.


How would you suggest that such a rigorously conclusive proof that it actually did happen be found and identified?

We already have proof that it /can/ happen. You're demanding proof that it already /has/ happened. How do you expect to find incontrovertible proof that a specific air crash was caused by a specific electronic interference somewhere among the millions of transistors in the aircraft's electronic system? How can this proof be found in a crashed and burned wreckage?

Also, how many people must die in such crashes before the proof becomes so solid that you think your life may perhaps be worth a couple of minutes' wait during takeoff and landing?
antialias_physorg
not rated yet Dec 30, 2011
the FCC requires that RF devices are tested and certified not to interfere with other devices.

There are various levels of inteference. E.g. if your device is admissible within a medical setting it must not exceed induced currents of 10mA at a certain distance (as far as I know this is the most stringent category).
I'm not sure how stringent the limits are in planes (but probably not much less).

Certification for normal devices is much more lenient. No phone maker needs to certify their phones for use in planes.

Broadcasting devices (phones, bluetooth/wireless headsets, tablets, ... ) can broadcast a lot of energy intentionally for communication purposes - even if their internal components are well shielded.

No conclusive proof exists that a consumer device has ever caused a flight system to malfunction.

I think we should really err on the side of caution, here.
It's next to impossible to tell where a flipped bit came from.
bluehigh
1.3 / 5 (13) Dec 31, 2011
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause undesired operation.

Furthermore your internal wires radiating are also prohibited ..

15.5(b) Operation of an intentional, unintentional, or incidental radiator is subject to the conditions
that no harmful interference is caused.

So that facts are that not only must consumer devices be certified NOT to cause harmful interference but that the airplane equipment must also be certified to not malfunction when exposed to interference.

.. and that is exactly what happens. No evidence whatsoever that consumer devices have ever harmed a flight system. Thanks to experts at the FCC.
bluehigh
1.3 / 5 (13) Dec 31, 2011
within a medical setting it must not exceed induced currents of 10mA at a certain distance
- antialias

You are just making it up. Whats this 'certain distance'. No reference.

Certification for normal devices is much more lenient.
- antialias

The certification requirements as I referenced previously are for ANY device not to be able to cause harm whether interfering or being interfered.

A flipped bit! Did you ever study error correction techniques in Elec Eng?

GuruShabu
1 / 5 (3) Dec 31, 2011
I've been reading all these comments since the beginning...there are very nice comments and some people really show a sound knowledge on the subject (such as antialias). However, some comments above he states that TVs are not ON during take off and landing.
This is not true.
One of the things I enjoy the most is tuning the screen on the nose wheel cam during take off and landing when I fly 777.
If you want I can send you a movie I take with my camera on this.
GuruShabu
1 / 5 (10) Dec 31, 2011
Sorry, I've forgotten to mention bluehigh that looks like knows more about the subject than antialias.
antialias_physorg
1 / 5 (1) Dec 31, 2011
One of the things I enjoy the most is tuning the screen on the nose wheel cam during take off and landing when I fly 777.

As noted: These are electronics that can be tested because it is KNOWN that they will be on the plane. There are a lot of electronic systems on at all times in a plane (all of the avionics, air conditioning, lighting, etc.). It is vital that they don't interfere with each other. You take them to EMF chambers and test them against each other. If they interfere then there's stuff you can do about it (extra shielding, capacitors in the right places to smooth out any current changes which act as RF sources, etc. )

There's electronics in operating rooms - and it must be ensured that these things don't interfere with pacemakers or each other. This stuff you HAVE to test beforehand.

Such tests are costly and timeconsuming. Just one reason why these gadgets are so dispropotionately expensive. This is not mandatory (to such a degree) for consumer electronics.
bluehigh
1.3 / 5 (12) Dec 31, 2011
So dangerous for people with Pacemakers to even walk the streets. With all the consumer gadgets, these people might be found dead on the sidewalk. Not to mention the noise in hearing aids or resonant howls in inductive loops embedded in cinemas for the partially deaf from passers-by using an RF device.

The FCC (and other regulatory agencies, surprising the FDA) ensure public safety. Thats why - no airplane incident has ever been attributed to RF interference from consumer device.