Wow, Title is a bit misleading; One piece of anecdotal evidence is no evidence at all. I would also like to take this time to bitch about the fact that airplane mode on many devices also prevents WiFi, which is allowed on board many flights.
My old nook couldn't do that. I had to have the mobile data on to use the Wifi on the flight. I briefly thought that that might (in a very unlikely scenario) result in my fiery demise, and not putting a particularly high value on my own life, continued to read wikipedia, It wasn't until I considered everyone else on board that I elected to switch back to airplane mode.
It's truly remarkable. It seems as if each word ("critical", "iPhone", etc) was chosen to maximize dissonance with what the article was actually about. Probably the work of an over zealous editor.
You are right, I changed it now to reflect a bit more what is in the article.
[edit] seems like I can't change it anymore. I tried changing it to "Airline industry still divided over usage of personal electronics and their supposed interference"
So there are less than 100 reports of interference of radio devices with planes. And then there is the study where 30% of the people said they do not turn off their devices.
The probability that something happens is minuscule, but above zero.
Other examples where the trade off between security and convenience has to be made is the driving of cars and liquids on a plane. I'm really curious in which direction this debate will swing. (FTR: I'm all for convenience ;) )
I'm pretty sure I read at least on of the NASA reports where the pilot in cooperation with the passenger positively identified that the interference stopped when the laptop was turned off, and started again when it was turned on.
Well, this isn't scientific discourse, it's about erring on the side of safety. And it's not like it's easy to get any other kind of evidence from actual flights.
>>Well, this isn't scientific discourse, it's about erring on the side of safety.
No. This is about security theater and nothing more. Beyond a few anecdotes, we have zero evidence that the practice of making people turn off their devices actually makes flights safer.
The article only states that it went away when the device was turned off. Unless you got this report from some other source, the "started again when it was turned on" part was not the claim.
The probability that the problem was cleared up coincidentally rather than as the result of one passenger turning off their phone is very low.
I'm pretty sure that only 30% of people admit to not turning off their devices. How many won't admit it? I'm pretty sure if they did a scan for Bluetooth devices during take-off the number would always be non-zero.
> The probability that the problem was cleared up coincidentally rather than as the result of one passenger turning off their phone is very low.
If I understand your first sentence correctly, you're saying that there is a high probability that the resolution of the problem was non-coincidental, i.e. turning off the phone solved the problem. This doesn't really gel with your second paragraph, though. Can you clarify?
I'm pretty sure that only 30% of people admit to not turning off their devices
On my recent flights, I've observed that very few of my neighbors completely powered off their devices and at least one did not turn on airplane mode (he told me so).
I would think that the 30% number is much higher, and probably rising as the years go on and more people forget or care less.
I'll admit to being in the 30%. I put my phone and Kindle in airplane mode to save battery power, but otherwise I leave my devices in their normal state. Is it 100% certain that none of my devices could possibly interfere with critical systems on the plane? Well, no, but 99.99% is good enough for me. And for what it's worth, I made my decision based on the available research plus what I learned based on my EE courses in school (my degree is in Computer Engineering, but I still took quite a few electrical engineering courses, including one on traveling waves).
Airplane mode should be 100% acceptable. The suspected interference is supposed to be caused by devices that broadcast "powerful" radio waves. Since airplane mode disables with the WiFi and the cellular antenna, it is impossible for the device to cause interference. At that point it becomes a completely self-contained mini-computer - probably much less harmful than, say, onboard television screens.
99.99% is 1::10,000. Multiply that by 643 million passengers per year (http://www.transtats.bts.gov/), and you get a lot of interference (64,300 passengers whose devices interfere...).
I believe that the chance of any typical passenger device interfering with critical plane systems is much less that 0.01%, but we need to be careful with seemingly unlikely events multiplied by large numbers.
30% of all airplane passengers never turn off their devices during flights. Now THAT is a large number of devices. How many of them interfered with critical plane systems, and what percentage of that interference caused an accident?
This is a situation where we need to move beyond platitudes and run some actual experiments, preferably random controlled trials. Load a couple of planes with several hundred smartphones and tablets each. Have the devices on one plane turned off and the devices on the other turned on. Fly a third plane completely empty as a control group. Measure the interference on all three planes and then compare the numbers.
Really? Let's follow your logic. There were 639 000 000 passengers last year. Lets say one tenth follow your thinking. Multiply that by .0001 you get 6390 potentially deadly events of interference. Would that be ok by you?
I tell you something it would not be ok by me if I was on one of those flights.
Of course the number is probably a lot lower than 0.0001. But it is still too high. The number of recorded events of interference are too high.
What this proves is that you are obviously not equipped to make decisions that affect my life and you should not try. You should follow the rules that are obviously the result of much more informed decision making that you are showing here.
And I wonder what part of your electrical engineering coursework makes you think it is ok to keep your devices on during takeoff. You certainly should know that your device emits EM waves even if it is in "airplane mode".
This is why statistics get people in trouble (and are only really useful for quantum physics and propaganda). He is measuring his certainty, you're measuring odds of interference, on top of which both are conjecture.
Regardless I am quite sure that he is far better 'equipped' to decide his own certainty, just as you are yours.
I guess I have to keep pointing out the obvious, but for airline safety a miniscule probability is often too high. I do not want a minuscule probability of death just so some moron cannot handle 5 min with a turned off cell-phone.
In these anecdotal reports, I'd like to see whether or not the actual navigation devices have been tested. In my opinion and past experience, it's possible that there actually is interference, but it's very like it's a result of a faulty/fragile board or bad shielding. In that case, it would seem like the prudent thing to do is to verify that it's not the actual device that is faulty/fragile, and routine testing of essential navigation devices should be as important as checking the engine.
Curious - why are people so damn resistant to turning off their devices for takeoff and landing, given the chance it _might_ be safer?
Even in the absence of hard data, I would prefer to ensure all cockpit instruments work with minimal interference, than read another email or send another tweet. Then when data is available to make a conclusion as to the effect or lack thereof, informed decisions can be used to create procedures.
People are so attached to their devices that they take any inconvenience towards using them as some sort of rights violation.
Because it isn't safer and the rule doesn't make sense. I don't like to follow arbitrary rules created by uninformed people, especially when they don't make sense and are inconvenient.
Are you an electrical engineer, or similarly educated in RF communications, and thus able to determine what is arbitrary?
I have been in tech for 29 years, and I am a licensed commercial pilot in both fixed wing and rotorcraft (but I don't work as a professional pilot.) I don't know what effect my iPhone would have on aircraft instruments, so I turn it off.
Pre-flight and in-flight procedures are based on what is known, and what helps to prevent problems from the unknown. The safety of flight is in part about not taking unnecessary risks. For example, if I have to visibility into a cloud (radar, instruments) I do not fly through a cloud.
I apply this logic to during the critical periods of takeoff and landing, if I am unsure a device that emits RF will affect my instruments, I shut it off. Inconvenience does not outweigh safety, even / especially if the effect on safety is unknown. The worst case scenario, although likely minor, is simple not worth the risk.
> Are you an electrical engineer, or similarly educated in RF communications, and thus able to determine what is arbitrary?
CpE here. The vast majority of communications links on planes use twisted-pair differential signaling [1], which is extremely resistant to RF interference.
I've also worked on test procedures for avionics equipment, and assure you that RF interference testing is a part of all test plans for such equipment. The types of interference we tested against were far more aggressive than those that any consumer electronics can emit.
Keep in mind that the FCC also aggressively regulates RF emissions from all consumer electronics devices. Testing against FCC regulations is an involved and expensive affair, and the vast majority of devices are forbidden from any powerful RF emissions.
> if I am unsure a device that emits RF will affect my instruments, I shut it off. Inconvenience does not outweigh safety, even / especially if the effect on safety is unknown. The worst case scenario, although likely minor, is simple not worth the risk.
If phones or other complex electronic devices truly can interfere with avionics, their presence should be forbidden in the passenger cabin. It wouldn't be hard to detect them during security screening.
I conjecture the reason that this hasn't happened is because the risk of such interference is a practical impossibility for the reasons stated above.
Speculation: legal liability ass covering. If they allow it and it ends up as the probable cause in a plane crash that kills x hundred people it's a major disaster and likely to lose everyone's involved jobs. If they continue with current policy it's a continued minor inconvenience that many people ignore anyway.
Payoff matrix is pretty much locked on status quo for now, maybe it will soften to "up to the airline but we advise against it" at some point and some of the smaller airlines will differentiate by allowing it and after a couple years the dam will burst.
It's because those are critical phases of flight, with an especially high workload on the pilots. This is also why small talk between pilots is disallowed during takeoffs and landings. If an instrument acts up in cruise, the pilots have a lot of time to figure things out, while an instrument acting during landing is much more likely to lead to dangerous situations.
It's rooted in a superficial theory of crowd psychology.
It doesn't really matter whether passengers obey the cabin crew in most situations, but the two you mention are exceptions. Particularly during landing, if some moron is dancing around in the aisle, she is likely to hurt herself or someone else. The airline is the only deep pocket in that situation, so it's considered very important that passengers submit at that time. The more random rules they can heap on (keep your windowshade up, keep all your items under the seat, no Gameboy-playing, etc.), the more cowed the passengers and the more rare the expensive injury lawsuit.
It's like those religions that really depend on their congregants' obeying to the point of never really thinking: all of those ban the consumption of alcohol.
Well that's an interesting and seemingly arbitrary characterization.
You see, I did not need to know what he said in order to know that the rule didn't make sense (although I do appreciate the info). There are a few problems with your default position of "minimize risk because we don't know". If you don't know, how is it different from the 13th floor being bad luck? Something bad might happen if you visit that floor. To minimize risk, we should just avoid it?
Generally, the burden of proof has to be on whoever makes a claim that something exists. The existence of the rule is essentially that claim. The creation of the rule was not backed by any particular study or data. You speak dismissively of what you perceive to be speculation, yet that is entirely what the rule is based on (you also said not being afraid of these ghosts is the paranoid behavior, but I digress).
To introduce a little logic - we know that this has more than likely been tested. The fact that it's a concern at all means it's a safe bet that experiments have been done. If said experiments found anything at all that causes danger to a flight, it defies reason that they would not implement a hard ban on the devices and screen for them. There would be penalties and fines. Instead, a polite attendant asks that they be turned off. Does this make sense to you? It tells me that they aren't very serious about it. There is no way that anything potentially dangerous would be trusted to "the honor system".
Once a rule is in place, it's difficult to change it, so it remains the default. Wireless signals are the modern day version of ghosts. They might cause cancer, they might crash planes, they might microwave your lunch. Of course, we have no reason to believe that they do any of these things - we just don't have a reason to believe that they don't. As a scientist, it is your duty to reject this invalid line of reasoning.
"If ... their presence should be forbidden in the passenger cabin"
It bears mentioning here that the FAA approves ipads in the cockpit itself as a replacement for flight charts[1]. And many airlines give their pilots ipads.
You seem to be operating from the assumption that the rules actually mean anything and somehow the vast majority of flights are done with all electronics following the rules. This is laughable. I'm sure that every flight with more than 100 people has at least a dozen bits of electronics still fully powered on and transmitting.
Why do I think it's safe? Because rules don't control reality, only people's behaviors do. In reality, we fly with our electronics on every single large flight, and they are not crashing or experiencing any particular problems. The only reason the rules are still there is that nobody wants to run the risk of being the one who gets blamed for some problem, because after some crash or something, somebody else who labors under the delusion that the rules actually mean something will pin the blame on the electronic devices, falsely, and by extension, the one who lifted the rules.
That's it. That's the only thing keeping this rule in place. It sure isn't physics. I don't have to be an EE or anything else, we've run this experiments hundreds of thousands or millions of times already.
That said, your little planes may have their own issues and this experience may not apply to your plane. But we're talking commercial flights here.
There are two assumptions that people in these discussion make
1) If 30% of the passengers leave their devices on today, leaving 100% of the devices on won't cause any increase in problems, and
2) If something happens it's either a) nothing, or b) the airplane falls out of the sky.
The fact is that an airplane is an incredibly complex machine. Instrument failures happen all the time, and pilots deal with this (they have redundant instruments and alternate procedures they can follow). If some of these problems happen due to interference from electronic devices, that's pretty much impossible to verify.
>I don't know what effect my iPhone would have on aircraft instruments, so I turn it off.
And my buddy at work takes flying lessons from a pilot who leaves his on so he can check weather and use other cute apps. As do probably numerous other less-enlightened pilots. So where is the epidemic of anomalous readings?
If airlines really believed that use of electronics could bring down an aircraft then they would ban passengers from using them entirely. Allowing passengers to take them on the plane and simultaneously claiming they are extremely dangerous is simply confusing. The passengers guess that the risk is being exaggerated as a way to control them so they resist on principle rather than because they care very much about using the devices.
Maybe everyone on the plane should pray that the equipment works properly, because it can't hurt!
The best argument I've heard is that its about distraction (EDIT: and in-cabin projectiles), and takeoff/landing are more prone to harsh landing situations.
Reminds me of how, as soon as a plane touches ground, people jump out of their seats and take their luggage… and then they stand around uncomfortably for ten minutes until they get to leave.
Well, no, you're wrong about that. If there really were anything other than superstition supporting the thesis that personal electronics could realistically and predictably have a deleterious effect on avionics, then that would indeed be a security issue.
>incompletely studied electronic effects.
Are you an electrical engineer, or similarly educated in RF communications, and thus able to determine whether the EMI testing that's been done is incomplete?
Seriously, how hard would it be to set up a rigorous test in an average airliner, noting what interference was detected, how much, and its objective effect on avionics?
That's why people are so resistant; the whole thing has the stench of unsubstantiated BS about it. Kinda like the TSA.
Well, it wouldn't necessarily be so hard to test a few devices on a plane.
But there are thousands of models of phones, tablets, wifi cards, 3g cards, bluetooth accessories, LTE/WiMax cards, gps devices, etc., etc., etc.
Then we get into the wide variety of planes in the air with varying amounts and types of avionics, radios, etc. And those systems are in different places in different planes.
And don't forget aftermarket alterations both in software and hardware (i.e. custom firmware, different batteries) to those devices.
So your test wouldn't be too hard, but the result it seems you want (i.e. a definitive answer on the safety of electronics use by passengers on aircraft) takes a hell of a lot more legwork.
They do perform those tests, but they can't account for all potential future electronics devices.
Likewise, you can test your database server for all known exploits and it might come up clean, but if you open your firewall you can still be hacked if someone later on finds a new exploit. A security minded person would ask you: "Was it _really_ necessary to open that port, of could you have inconvenienced your developers a little bit and made them use a VPN instead?"
Trust me, this isn't the only rule in aviation that seems stupid, but the mindset that results in rules like this has had a positive effect on aviation safety.
They do perform those tests, but they can't account for all potential future electronics devices.
So, our defense against potentially dangerous future electronics devices is a generic safety announcement at the beginning of the flight with only cursory verification that it was followed?
Yes. This is a trade-off. Do they search your hand luggage for air band radios? No, they don't. That's also a trade-off, even though you could certainly cause interference with one.
It's also logically inconsistent. Either the threat of interference and danger is great enough to warrant bag checks, or it is not, and this threat is overblown like every other "threat" in air travel nowadays.
Of course it's logically inconsistent, but this is the real world and trade-offs like these are made. Same with Lithium batteries, although there have been several confirmed cases of such batteries catching fire in flight they are still allowed. It's just not feasible to ban cell phones and laptops.
Likewise, airlines have a "clean cockpit" policy disallowing small talk during landings. Do they monitor the CVRs and fine pilots who break this rule? I don't think so. Will some pilots find the rule exessive and make exceptions? Maybe. But the rule still has an effect, and is in place because of previous accidents where distracted pilots have been a contributing factor.
While I think this rule about electronic devices might be too stringent, and that it will eventually change, I don't think the airlines have overblown it. Pilots will handle instrument failures gracefully in 99.99% of all cases, and then there's the fatal accident where some stupid malfunction caused the pilot to screw up (AF447, and many others before). Because they know this is a "numbers game", they try to minimize potential problems, even though they may not be able to eliminate them altogether.
Because I think it's bullshit (either superstition or a lie). "Might sometimes interfere in an undefined way with an unspecified device" is a non-falsifiable claim.
If somebody told me not to fart during takeoff and landing (because it might change trajectory of the plane — you never know…), then I'd still protest even though it _might_ be safer not to fart.
Phones are supposed to pass FCC EMI tests and I expect planes' electronics to be properly hardened/shielded from EMI even stronger than tiny consumer devices can produce.
Because there are far more electronics in the plane than in any of my devices, and it's ridiculously easy to disable radio communication. Until they force me to turn off my device or provide me with a compelling reason that it could interfere with anything, I'm just going to write this request off as irrational luddism.
Flying on a plane is already far and away the most miserable way for me to travel, don't take away my goddamn ipod.
Because this is faith based "safety" and if there really is an issue, then it's a huge safety & security problem with avionics, not with personal portable electronics. A problem that ought to be addressed, rather than naively hoping for the best.
I think a better question is why are you so resistant to making a sacrifice to Zeus, god of lightning, on the off chance it __might__ be helpful? There's a lot more evidence for Zeus than there is for iPods bringing down airplanes. (Lightning bolts are real, but there has never been a documented incident of the latter thing.)
If they can come to my seat and tell me to turn off my device because they detected a source of interference, then I will turn off the device. If they can't or aren't willing to detect the source of interference, the real risk is likely dubious.
Furthermore, avionics equipment should be and is designed to work despite minor external interference. If a consumer electronics device, such as an iPhone or laptop, could drastically effect the operation of avionics equipment, it should not be considered flight worthy. Granted, certification tests probably don't consider such radiation sources, but the risk is so small its likely its not even worth testing.
I'm sorry but your first sentence is just bad logic. Just to play devil's advocate, while you are on the ground/taxi-ing in the plane, let's say that you play a disconnected game (one that is a single player game and requires no connection of any kind). No interference is detected. An hour into the flight, you launch an app that proceeds to send your contact list to their home servers. You surely don't expect the pilots to stop what they are doing and come show you, "Look - here's what the problem you are causing is. Turn off your phone!"
The second paragraph - sure, fine. I think that's what we all want to know.
>You surely don't expect the pilots to stop what they are doing and come show you, "Look - here's what the problem you are causing is. Turn off your phone!"
No, but I would expect one of the pilots to notice something that looks, smells, or feels like electronic interference, and ask the FA's to make an announcement asking everyone to make sure their devices are off because actual interference has been found and is causing a problem.
I agree with you that the FAA has done a poor job of explaining what electrical interference there is, and what it's effects are. I also agree that avionics gear is not so sensitive that an iPhone's connection should harm it. But your argument that the pilot should deal with problems like this in-flight is just a tad bit on the silly side IMO.
The typical pilot's mindset is, "Fly the plane but, when a problem occurs, stop focusing on flying the plane and solve/identify the problem. Once the problem is solved/identified, get back to flying the plane." You're effectively wanting to change this to something more like, "Fly the plane but, when a problem occurs, stop focusing on flying the plane and solve/identify the problem except if the problem is 'electrical interference'. If that's the case, ask yet again that people turn their phones off. Hopefully they'll listen this time. Wait for all of the people to comply and, once the problem is solved, get back to flying the plane."
It just sounds silly, doesn't it? I think we'd all agree that, if there's a problem with electrical interference during flight, we want the pilot to be flying the plane rather than having him/her wait for the passengers to do anything. Again - I'm not arguing whether this is right/wrong; I'm simply pointing out that the logic of having a pilot wait on passenger behaviors before being able to continue doing his/her job is a bit silly.
Admittedly yes, but I think the average person would have a different reaction to "Hey, someone's electronics are actually causing an actual problem, shut down everything" rather than ignored much like the safety briefing that any air traveler who has flown more than twice can recite from memory.
Why? Because anyone who has flown and forgot to put their phone in airplane mode and didn't experience a firey death can attest, the usual warnings lack both urgency and a factual connection to reality. Having them announce "there is a problem due to interference" solves both of these.
You want pilots to be troubleshooting malfunctioning avionics and summoning FA's to try to find someone's iPhone during a critical phase of flight, for no other reason than to allow a passenger the convenience of not having to shut his phone off? No thanks.
Karunamon is not asking for them to find a specific phone, just make a general announcement for everyone to double-check that their phones are off, and possibly to specifically cite interference as the reasoning.
Yeah. Maybe I'm just weird, but when I'm in a commercial jet loaded with a couple hundred people and 40,000 liters of jet fuel, and we're in those critical phases of flight, I don't want anything going wrong with the avionics on that plane. I don't want any malfunctions or errors, even if those malfunctions can be alleviated by the FA's making an announcement requesting that everyone shut off their phone.
Hearing, "if there's problems, we'll just have the FA's make an annoucement" doesn't exactly quiet my concerns. If we're going to be using our smartphones on airplanes I want it to be after thorough, deliberate, conclusive testing has been done that proves that the aircraft is safe to fly with hundreds of cell phones transmitting in the passenger compartment.
I'm sorry but your first sentence is just bad logic.
I don't see a problem with the logic. If personal electronic devices could truly cause interference, then just reminding people to turn off devices seems like pretty weak protection.
How many people intentionally or unintentionally leave an electronic device powered on during any given flight? I know I've forgotten to turn off my phone a couple of times in the past.
Only going as far as reminding people to turn off devices is the equivalent of airport security checkpoints that just have a person standing there reminding people to remove dangerous items from their bags before boarding.
Devices emit radiation whether they are using the radio or not. If its burning power, there is an emission, albeit small in comparison and probably hard to detect without specialized instruments.
If the radios are simply on, link layer protocols will be transmitting control signals that can easily be detected with something as simple as a smart phone.
I think the safety culture is, if you can't prove it is safe, you may not assume that it is. This places the burden of proof on the other side. I don't see any more quantitative arguments from you.
This conservative approach is a pain, it's slow, it's expensive. But it's hard to have such a safe environment for commercial aviation without a similar culture.
That's a fine sounding slogan but back in reality, your safety culture turns out to be a farce. Compliance is impossible to ensure, and this will only get worse. Continued insistence upon this farce erodes confidence and respect in the competence of the authorities, and in the flight crews carrying out the policies. It's also hard to have a safe environment where the authorities are widely regarded as buffoons.
>I don't see any more quantitative arguments from you.
You're arguing pretty hard here. I'm not with the FAA, so it's not "my" safety culture you're arguing against. I actually don't have a strong opinion on this matter (I'm an EE PhD, but without particular expertise in RF; I don't feel qualified to have a strong opinion on RF effects across all commercial airliners).
OTOH, I do have some insight into aeronautical safety, and I'm trying to present that viewpoint, which is clearly lacking in this comment thread.
I think you forget that many of these instruments have _antennas_. While they are very well insulated against unwanted interference, it's not like it's feasible to protect against _any_ interference. After all, the pilots are talking on an unencrypted air band with the tower, and the same is the case with DME, VOR, ILS and GPS.
Yes. Furthermore, if the people responsible for these rules really believe there is a need for them then surely they are being derelict in not requiring RF monitoring devices in the cabin.
Unless of course the interference comes when the plane is already in flight, at which point your notice that your phone causes interference may come when you catch on fire.
Avionics design must be resistant to interference.
Unfortunately, perfect resistance is impossible (see GPS and LightSquared).
The notion that you should turn off "anything with an off switch" as an open-loop solution to the problem is folly. Short of removing the batteries from a device, it's hardly guaranteed that it is truly de-powered.
Furthermore, plenty of things don't have an off switch. Pebble watches run via Bluetooth. I doubt users think to turn them off.
It's not an easy problem. Sealing the passenger cabin into a Faraday cage may be the only way to ensure RF isolation of instrumentation.
On the subject of LightSquared, I know quite a few people who belonged to that project and I think there's a lot more going on there than meets the eye.
In the days following the DoD test for GPS there were a lot of outcries of fraudulent testing parameters that got thrown around and were never really resolved to anyones satisfaction. I still contend that low-orbit satellites can provide a potent and real alternative to the wireless systems we have today (or at least as a distribution path for backhaul).
I'm still quite hopeful that the LightSquared kids will get a spectrum swap now that Obama has been settled in the office for a while. Here's hoping; it would be a net-boon for the whole wireless industry.
Why isn't the passenger cabin sealed into a faraday cage? I would think that would have been the first thing they would build into a plane once devices that broadcast RF became common.
I also am quite bad at classical physics, so I don't know the limitations of such a cage.
Nope, there are windows. That's why your microwave has that grid-looking stuff over the windows. It keeps the cage intact and avoids cooking your eyeballs when you look in.
The passenger cabin is already a pretty good approximation of a Faraday cage. As far as aircraft GPS go, their antenna is on the outside of the fuselage, top, (because it wouldn't receive a signal on the inside) and connected to the GPS receiver with a shielded coaxial cable. So, I'm not buying any of this nonsense about cell phones and readers and video games mucking up the GPS.
RF is somewhat like magic. Crappy 802.11 devices can cause interference with radios and antennas. I have one computer system that I can't use in the same room with a HAM radio. It causes too much interference. When I shut it off, everything works fine.
Remember that sound your computer speakers made when you put your old cell phone near them? Try landing a plane and listening to direction from the tower with that going on in your headset. Interference is a real thing and mitigating it is just a small inconvenience to the passenger who entrust their lives to their pilots.
So where are the tests? Actual reports, not anecdotes? The whole FAA report is based on word-of-mouth from flight crew. Surely the industry can spare some change for research in such an important area.
I have a friend who's a pilot for one of the major commercial airlines. He uses his iPhone during flights all the time (seems to be common among pilots). I guess only the passengers are subject to the regulations. Though, I do realize that the pilots can easily turn theirs off if there's an issue; it's a little harder to track down the phone causing problems if it's one of the passengers'.
Regardless, the data doesn't seem to concretely prove that phones are causing any of the problems
Like using mobile phones at gas stations, this is an issue I've heard numerous justifications for over the years.
One interesting one was the health effects of having 200-300 mobile phones ranging at full power inside a sealed metal tube in the sky. Not so much an issue for passengers, but flight crew on long haul flights subject to these signal levels for 8 or 9 hours several days a week! Obviously Airplane mode would solve this but telling everyone to switch off sounds a better way of enforcing this. Of course this assumes there are any adverse health effects from mobile phones at all, but that's a whole different can of worms.
Another 'theory', I've since dismissed, relating to the requirement to switch off particularly at take off and landing, is because a plane load of 300 mobiles roaming between base stations at 400mph can cause the mobile operators a few headaches!
Do you have any idea how much ionizing radiation simply being in the upper atmosphere exposes you to? Whoever made that claim apparently doesn't. They probably don't know the difference between ionizing and non-ionizing radiation either. Which means you should not pay any attention to them.
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[ 4.3 ms ] story [ 176 ms ] thread[edit] seems like I can't change it anymore. I tried changing it to "Airline industry still divided over usage of personal electronics and their supposed interference"
The probability that something happens is minuscule, but above zero.
Other examples where the trade off between security and convenience has to be made is the driving of cars and liquids on a plane. I'm really curious in which direction this debate will swing. (FTR: I'm all for convenience ;) )
The reports are for suspected interference. It has never been proven beyond reasonable doubt.
No. This is about security theater and nothing more. Beyond a few anecdotes, we have zero evidence that the practice of making people turn off their devices actually makes flights safer.
I'm pretty sure that only 30% of people admit to not turning off their devices. How many won't admit it? I'm pretty sure if they did a scan for Bluetooth devices during take-off the number would always be non-zero.
If I understand your first sentence correctly, you're saying that there is a high probability that the resolution of the problem was non-coincidental, i.e. turning off the phone solved the problem. This doesn't really gel with your second paragraph, though. Can you clarify?
On my recent flights, I've observed that very few of my neighbors completely powered off their devices and at least one did not turn on airplane mode (he told me so).
I would think that the 30% number is much higher, and probably rising as the years go on and more people forget or care less.
And how many don't even know?
99.99% is 1::10,000. Multiply that by 643 million passengers per year (http://www.transtats.bts.gov/), and you get a lot of interference (64,300 passengers whose devices interfere...).
I believe that the chance of any typical passenger device interfering with critical plane systems is much less that 0.01%, but we need to be careful with seemingly unlikely events multiplied by large numbers.
This is a situation where we need to move beyond platitudes and run some actual experiments, preferably random controlled trials. Load a couple of planes with several hundred smartphones and tablets each. Have the devices on one plane turned off and the devices on the other turned on. Fly a third plane completely empty as a control group. Measure the interference on all three planes and then compare the numbers.
But perhaps not for the other passengers, which is the issue here.
Really? Let's follow your logic. There were 639 000 000 passengers last year. Lets say one tenth follow your thinking. Multiply that by .0001 you get 6390 potentially deadly events of interference. Would that be ok by you?
I tell you something it would not be ok by me if I was on one of those flights.
Of course the number is probably a lot lower than 0.0001. But it is still too high. The number of recorded events of interference are too high.
What this proves is that you are obviously not equipped to make decisions that affect my life and you should not try. You should follow the rules that are obviously the result of much more informed decision making that you are showing here.
And I wonder what part of your electrical engineering coursework makes you think it is ok to keep your devices on during takeoff. You certainly should know that your device emits EM waves even if it is in "airplane mode".
Regardless I am quite sure that he is far better 'equipped' to decide his own certainty, just as you are yours.
Even in the absence of hard data, I would prefer to ensure all cockpit instruments work with minimal interference, than read another email or send another tweet. Then when data is available to make a conclusion as to the effect or lack thereof, informed decisions can be used to create procedures.
People are so attached to their devices that they take any inconvenience towards using them as some sort of rights violation.
And I would reiterate, this is during the brief period of takeoff and landing.
I have been in tech for 29 years, and I am a licensed commercial pilot in both fixed wing and rotorcraft (but I don't work as a professional pilot.) I don't know what effect my iPhone would have on aircraft instruments, so I turn it off.
Pre-flight and in-flight procedures are based on what is known, and what helps to prevent problems from the unknown. The safety of flight is in part about not taking unnecessary risks. For example, if I have to visibility into a cloud (radar, instruments) I do not fly through a cloud.
I apply this logic to during the critical periods of takeoff and landing, if I am unsure a device that emits RF will affect my instruments, I shut it off. Inconvenience does not outweigh safety, even / especially if the effect on safety is unknown. The worst case scenario, although likely minor, is simple not worth the risk.
CpE here. The vast majority of communications links on planes use twisted-pair differential signaling [1], which is extremely resistant to RF interference.
I've also worked on test procedures for avionics equipment, and assure you that RF interference testing is a part of all test plans for such equipment. The types of interference we tested against were far more aggressive than those that any consumer electronics can emit.
Keep in mind that the FCC also aggressively regulates RF emissions from all consumer electronics devices. Testing against FCC regulations is an involved and expensive affair, and the vast majority of devices are forbidden from any powerful RF emissions.
> if I am unsure a device that emits RF will affect my instruments, I shut it off. Inconvenience does not outweigh safety, even / especially if the effect on safety is unknown. The worst case scenario, although likely minor, is simple not worth the risk.
If phones or other complex electronic devices truly can interfere with avionics, their presence should be forbidden in the passenger cabin. It wouldn't be hard to detect them during security screening.
I conjecture the reason that this hasn't happened is because the risk of such interference is a practical impossibility for the reasons stated above.
1. http://en.wikipedia.org/wiki/Differential_signaling
That said, care to speculate why the prohibition on device use during takeoff / landing?
Payoff matrix is pretty much locked on status quo for now, maybe it will soften to "up to the airline but we advise against it" at some point and some of the smaller airlines will differentiate by allowing it and after a couple years the dam will burst.
It doesn't really matter whether passengers obey the cabin crew in most situations, but the two you mention are exceptions. Particularly during landing, if some moron is dancing around in the aisle, she is likely to hurt herself or someone else. The airline is the only deep pocket in that situation, so it's considered very important that passengers submit at that time. The more random rules they can heap on (keep your windowshade up, keep all your items under the seat, no Gameboy-playing, etc.), the more cowed the passengers and the more rare the expensive injury lawsuit.
It's like those religions that really depend on their congregants' obeying to the point of never really thinking: all of those ban the consumption of alcohol.
You see, I did not need to know what he said in order to know that the rule didn't make sense (although I do appreciate the info). There are a few problems with your default position of "minimize risk because we don't know". If you don't know, how is it different from the 13th floor being bad luck? Something bad might happen if you visit that floor. To minimize risk, we should just avoid it?
Generally, the burden of proof has to be on whoever makes a claim that something exists. The existence of the rule is essentially that claim. The creation of the rule was not backed by any particular study or data. You speak dismissively of what you perceive to be speculation, yet that is entirely what the rule is based on (you also said not being afraid of these ghosts is the paranoid behavior, but I digress).
To introduce a little logic - we know that this has more than likely been tested. The fact that it's a concern at all means it's a safe bet that experiments have been done. If said experiments found anything at all that causes danger to a flight, it defies reason that they would not implement a hard ban on the devices and screen for them. There would be penalties and fines. Instead, a polite attendant asks that they be turned off. Does this make sense to you? It tells me that they aren't very serious about it. There is no way that anything potentially dangerous would be trusted to "the honor system".
Once a rule is in place, it's difficult to change it, so it remains the default. Wireless signals are the modern day version of ghosts. They might cause cancer, they might crash planes, they might microwave your lunch. Of course, we have no reason to believe that they do any of these things - we just don't have a reason to believe that they don't. As a scientist, it is your duty to reject this invalid line of reasoning.
It bears mentioning here that the FAA approves ipads in the cockpit itself as a replacement for flight charts[1]. And many airlines give their pilots ipads.
[1] http://en.wikipedia.org/wiki/Cockpit_iPads
Why do I think it's safe? Because rules don't control reality, only people's behaviors do. In reality, we fly with our electronics on every single large flight, and they are not crashing or experiencing any particular problems. The only reason the rules are still there is that nobody wants to run the risk of being the one who gets blamed for some problem, because after some crash or something, somebody else who labors under the delusion that the rules actually mean something will pin the blame on the electronic devices, falsely, and by extension, the one who lifted the rules.
That's it. That's the only thing keeping this rule in place. It sure isn't physics. I don't have to be an EE or anything else, we've run this experiments hundreds of thousands or millions of times already.
That said, your little planes may have their own issues and this experience may not apply to your plane. But we're talking commercial flights here.
1) If 30% of the passengers leave their devices on today, leaving 100% of the devices on won't cause any increase in problems, and
2) If something happens it's either a) nothing, or b) the airplane falls out of the sky.
The fact is that an airplane is an incredibly complex machine. Instrument failures happen all the time, and pilots deal with this (they have redundant instruments and alternate procedures they can follow). If some of these problems happen due to interference from electronic devices, that's pretty much impossible to verify.
And my buddy at work takes flying lessons from a pilot who leaves his on so he can check weather and use other cute apps. As do probably numerous other less-enlightened pilots. So where is the epidemic of anomalous readings?
The best argument I've heard is that its about distraction (EDIT: and in-cabin projectiles), and takeoff/landing are more prone to harsh landing situations.
The argument is similar to subjecting yourself to radiation in the off chance that it (scanner) might detect yourself as a terrorist.
Also this is not a security issue (one of persons with malicious intent). It is a safety issue, one of incompletely studied electronic effects.
>incompletely studied electronic effects.
Are you an electrical engineer, or similarly educated in RF communications, and thus able to determine whether the EMI testing that's been done is incomplete?
That's why people are so resistant; the whole thing has the stench of unsubstantiated BS about it. Kinda like the TSA.
But there are thousands of models of phones, tablets, wifi cards, 3g cards, bluetooth accessories, LTE/WiMax cards, gps devices, etc., etc., etc.
Then we get into the wide variety of planes in the air with varying amounts and types of avionics, radios, etc. And those systems are in different places in different planes.
And don't forget aftermarket alterations both in software and hardware (i.e. custom firmware, different batteries) to those devices.
So your test wouldn't be too hard, but the result it seems you want (i.e. a definitive answer on the safety of electronics use by passengers on aircraft) takes a hell of a lot more legwork.
Likewise, you can test your database server for all known exploits and it might come up clean, but if you open your firewall you can still be hacked if someone later on finds a new exploit. A security minded person would ask you: "Was it _really_ necessary to open that port, of could you have inconvenienced your developers a little bit and made them use a VPN instead?"
Trust me, this isn't the only rule in aviation that seems stupid, but the mindset that results in rules like this has had a positive effect on aviation safety.
So, our defense against potentially dangerous future electronics devices is a generic safety announcement at the beginning of the flight with only cursory verification that it was followed?
Likewise, airlines have a "clean cockpit" policy disallowing small talk during landings. Do they monitor the CVRs and fine pilots who break this rule? I don't think so. Will some pilots find the rule exessive and make exceptions? Maybe. But the rule still has an effect, and is in place because of previous accidents where distracted pilots have been a contributing factor.
While I think this rule about electronic devices might be too stringent, and that it will eventually change, I don't think the airlines have overblown it. Pilots will handle instrument failures gracefully in 99.99% of all cases, and then there's the fatal accident where some stupid malfunction caused the pilot to screw up (AF447, and many others before). Because they know this is a "numbers game", they try to minimize potential problems, even though they may not be able to eliminate them altogether.
If somebody told me not to fart during takeoff and landing (because it might change trajectory of the plane — you never know…), then I'd still protest even though it _might_ be safer not to fart.
Phones are supposed to pass FCC EMI tests and I expect planes' electronics to be properly hardened/shielded from EMI even stronger than tiny consumer devices can produce.
Flying on a plane is already far and away the most miserable way for me to travel, don't take away my goddamn ipod.
Furthermore, avionics equipment should be and is designed to work despite minor external interference. If a consumer electronics device, such as an iPhone or laptop, could drastically effect the operation of avionics equipment, it should not be considered flight worthy. Granted, certification tests probably don't consider such radiation sources, but the risk is so small its likely its not even worth testing.
The second paragraph - sure, fine. I think that's what we all want to know.
No, but I would expect one of the pilots to notice something that looks, smells, or feels like electronic interference, and ask the FA's to make an announcement asking everyone to make sure their devices are off because actual interference has been found and is causing a problem.
The typical pilot's mindset is, "Fly the plane but, when a problem occurs, stop focusing on flying the plane and solve/identify the problem. Once the problem is solved/identified, get back to flying the plane." You're effectively wanting to change this to something more like, "Fly the plane but, when a problem occurs, stop focusing on flying the plane and solve/identify the problem except if the problem is 'electrical interference'. If that's the case, ask yet again that people turn their phones off. Hopefully they'll listen this time. Wait for all of the people to comply and, once the problem is solved, get back to flying the plane."
It just sounds silly, doesn't it? I think we'd all agree that, if there's a problem with electrical interference during flight, we want the pilot to be flying the plane rather than having him/her wait for the passengers to do anything. Again - I'm not arguing whether this is right/wrong; I'm simply pointing out that the logic of having a pilot wait on passenger behaviors before being able to continue doing his/her job is a bit silly.
Why? Because anyone who has flown and forgot to put their phone in airplane mode and didn't experience a firey death can attest, the usual warnings lack both urgency and a factual connection to reality. Having them announce "there is a problem due to interference" solves both of these.
If a passenger's device is causing actual interference, then what other option does the pilot have?
You want pilots to be troubleshooting malfunctioning avionics and summoning FA's to try to find someone's iPhone during a critical phase of flight, for no other reason than to allow a passenger the convenience of not having to shut his phone off? No thanks.
Hearing, "if there's problems, we'll just have the FA's make an annoucement" doesn't exactly quiet my concerns. If we're going to be using our smartphones on airplanes I want it to be after thorough, deliberate, conclusive testing has been done that proves that the aircraft is safe to fly with hundreds of cell phones transmitting in the passenger compartment.
I don't see a problem with the logic. If personal electronic devices could truly cause interference, then just reminding people to turn off devices seems like pretty weak protection.
How many people intentionally or unintentionally leave an electronic device powered on during any given flight? I know I've forgotten to turn off my phone a couple of times in the past.
Only going as far as reminding people to turn off devices is the equivalent of airport security checkpoints that just have a person standing there reminding people to remove dangerous items from their bags before boarding.
If the radios are simply on, link layer protocols will be transmitting control signals that can easily be detected with something as simple as a smart phone.
Flying in the upper atmosphere? Loads of radiation. A lot more than any phone.
RF in multipath environments tends to be spooky.
This conservative approach is a pain, it's slow, it's expensive. But it's hard to have such a safe environment for commercial aviation without a similar culture.
>I don't see any more quantitative arguments from you.
You don't see, or you don't care to see?
OTOH, I do have some insight into aeronautical safety, and I'm trying to present that viewpoint, which is clearly lacking in this comment thread.
The person next to me just lied and said he had and ipod touch ...
Unfortunately, perfect resistance is impossible (see GPS and LightSquared).
The notion that you should turn off "anything with an off switch" as an open-loop solution to the problem is folly. Short of removing the batteries from a device, it's hardly guaranteed that it is truly de-powered.
Furthermore, plenty of things don't have an off switch. Pebble watches run via Bluetooth. I doubt users think to turn them off.
It's not an easy problem. Sealing the passenger cabin into a Faraday cage may be the only way to ensure RF isolation of instrumentation.
On the subject of LightSquared, I know quite a few people who belonged to that project and I think there's a lot more going on there than meets the eye.
In the days following the DoD test for GPS there were a lot of outcries of fraudulent testing parameters that got thrown around and were never really resolved to anyones satisfaction. I still contend that low-orbit satellites can provide a potent and real alternative to the wireless systems we have today (or at least as a distribution path for backhaul).
I'm still quite hopeful that the LightSquared kids will get a spectrum swap now that Obama has been settled in the office for a while. Here's hoping; it would be a net-boon for the whole wireless industry.
/End Tangent
I also am quite bad at classical physics, so I don't know the limitations of such a cage.
Regardless, the data doesn't seem to concretely prove that phones are causing any of the problems
Passenger electronics are so obviously safe that screening for them would break suspension of disbelief even in the airport security theater.
One interesting one was the health effects of having 200-300 mobile phones ranging at full power inside a sealed metal tube in the sky. Not so much an issue for passengers, but flight crew on long haul flights subject to these signal levels for 8 or 9 hours several days a week! Obviously Airplane mode would solve this but telling everyone to switch off sounds a better way of enforcing this. Of course this assumes there are any adverse health effects from mobile phones at all, but that's a whole different can of worms.
Another 'theory', I've since dismissed, relating to the requirement to switch off particularly at take off and landing, is because a plane load of 300 mobiles roaming between base stations at 400mph can cause the mobile operators a few headaches!