Nice article, but it didn't mention the most telling data point about the nonsense basis for these rules - the lack of any sort of onboard EM detection.
Any other measurable factor that can conceivably have an impact on a flight has an instrument, or many, devoted to it. If mobile phones were of any risk whatsoever, there'd be a flashing light in the cockpit if something on board was radiating on a phone frequency. The cabin crew would then sweep the cabin with a detector to find the offending person. Instead, they rely on a visual search of items the passengers have in their hands only!
The fact is that there are two parties with real skin in this game - the manufacturers and the airlines. It's those parties whose are motivated and empowered to evaluate the actual risk of EM emissions on a flight, and to take concrete actions to mitigate the risk if the if the danger proved genuine.
In over 20 years since the general availability of mobile phones neither of these parties have taken these actions, or made any sign of needing or wanting to do so, and IMO that says all you need to know about the for-show-only nature of these rules.
Your suggestion is illogical and unworkable. Because the time take to search the plane for transmitting phones would be anywhere from 0 to say 30 mins for a phone left on at the bottom of a suitcase.
How on earth would you then schedule flights when you don't have a fixed journey time ? How would connecting flights work ?
Airlines revolve around managing risk. They don't ground flights during wet weather even though it's slightly more risky to fly. Likewise they don't need to switch off every phone. Just enough of them to get the risk down to an acceptable threshold.
You could also imagine that the punishment for leaving a cell-phone was much more severe. I'm not totally in agreement with the article, but it is strange that the airline claims a phone that's switched on is a major problem, yet the way of enforcing that they are of is by giving stern looks.
The rule can very easily be broken which suggests that it is useless. They either have much stricter enforcement or none at all.
The comparison with weather conditions is problematic since there is no way to control the weather while you could introduce a detection system and severe punishments for cell phone use.
You seem to be missing the key point here: risk management.
Nobody has said that phones are a major risk compared to all of the other risks a plane has to deal with e.g. weather, maintenance, pilot experience. Only that they do represent a risk and the status quo represents the most reasonable way to manage it.
What evidence do you have that stricter enforcement is warranted ?
> Only that they do represent a risk and the status quo represents the most reasonable way to manage it.
And yet, the status quo dictates employing people to throw out water bottles you purchased at the duty free after already having been screened for it yourself (and probably screened the store's inventory as it was coming in). And consider nail cutters a deadly weapon.
I did not read the GP to say that stricter enforcement was warranted - just that it was not in-line with how other controllable risks associated with passengers risks treated.
And yet somehow they manage to inspect the entire passenger manifest for evil nailclippers without making people miss their flight.
If there was a genuine risk, there would be an effort to screen electronic devices by their EM spectrum prior to boarding, with some devices forcibly travelling as checked luggage in an EM-shielded area. There is no such screening, hence there is no such risk. The rule exists to make you believe that your security is being taken seriously. It's a ritual that makes passengers more docile during take-off and landing, just like many of the other pre-flight safety instructions given by a cabin crew.
I violate this rule all the time. It's pure superstition, and verifiably wrong. Rules like this cause a distrust of ALL rules, making people think twice about following rules that actually are necessary. That's why having misguided rules like this makes us less safe.
No, but I didn't claim that I have it.
That bit of back-of-the-envelope calculation in the article does not justify a claim anywhere close to 'verifiable wrong'.
What a load of shit. There have been studies made that show electronic devices disturbing airplane systems. There are many recorded incidents of interference. The WSJ call these "anecdotal evidence" but they happened, and they were documented by the FAA.
Just think for a second about the term "anecdotal evidence." What really is the problem with "anecdotal evidence?" Well the term is an example of a logical fallacy only when one seeks to deduce broad all encompassing conclusions from such evidence. Thus, for example, if you see one drunken irish person it does not follow that irish are drunks. It is anecdotal evidence. But does the same logic follow for plane crashes? I suppose if you have one recorded event of a device interfering with flight instrumentation, you could call that "anecdotal evidence." But what if the plane crashes and it kills 300 people? Well that would still be a rare occurrance, and you could still call this an anecdote. But it would also be a terrible tragedy.
You see, rare occurrences are not sufficient to create an overall rule about the majority of cases, but they are sufficient to create tragedies. I am willing to bet that even most drunk drivers end up getting home safely. Then why ban drunk driving? Because the danger of death even if relatively rare is still unacceptable. Because we value life in this country. So my point is that the usual rule against anecdotal evidence does not apply when dealing with airline safety. In airline safety even things that happen very rarely can be a problem. Because, again, we value our lives.
Their other point is also rather dumb. They say that they did a survey that showed that many people do not turn off their devices completely and few people (2%) even use them blatantly. The thinking here goes a little bit like this: "since some people broke the rules and no disaster happened then it must be ok for more people to break the rule". This is train of logic is similar to the one used in the Peter Principle. This kind of thinking is basically guaranteed to result in a disaster. Because, every time they would say "well nothing bad has happened thus far, so we might as well increase the sources interference", and this will go on until something bad happens.
Could you cite said studies? I studied aerospace engineering in college and was taught that there is no evidence of this beyond a pilot and some air hostesses, at some point a few decades ago, hypothesising that some avionics error was caused by passenger electronics.
There is a comprehensive database of civil air traffic accident, compiled with IATA, on http://planecrashinfo.com/database.htm. I have yet to see anything cell phone-related.
A quick google search reveals a study including a case where the pilot in cooperation with the passenger identified his laptop as causing interference on navigation instruments.
Is it really too much to ask to do a quick Google search?
Yes, anybody can do a google search. You can also do a google search for "9/11 was an inside job" and "JFK killed Marilyn." Doesn't mean that the first google hit is a study that is reliable, repeatable, or even factual.
I didn't tell you to look at the first Google hit, did I? But if you're going to voice your opining, I do expect a minimal amount of effort to educate yourself. You can easily find reports hosted by for instance NASA, and to discredit those you have to thing that pilots are imagining things or part of a worldwide conspiracy.
However, most people here seem content to disregard any evidence that may contradict their beliefs.
The real reason why PEDs are still banned are because neither FAA, airlines or manufacturers have been willing to perform comprehensive studies in order to determine the effects on planes.
The reason we have WiFi access on planes nowadays is because very detailed and expensive studies have been done, and improved shielding has been added to certified planes. Apparently such studies are underway, but risk-aversion in the aviation industry means nothing is going to change before the results of those studies are in.
I'm a private pilot and I leave my cell phone on as a safety measure in case the radio breaks down. I disable cell data and try to place it away from the avionics so I get a minimu amount of noise in my headset. However, if I was instrument rated, I wouldn't attempt an instrument approach in minimal weather conditions with my cell phone on. I can't conclusively prove that my phone is incapable of influencing the instruments, but I'd rather not find out "the hard way".
I found this study and at the end is an interesting summary from the RTCA:
"Those findings indicated that the probability of interference to installed aircraft systems from PED, singly or in multiples, is extremely slight. However, the slight possibility of interference to aircraft navigation and information systems during critical phases of flight, e.g., takeoff and landing, should be viewed as potentially hazardous and an unacceptable risk for aircraft involved in passenger carrying operations. Therefore, the committee recommends that the use of PEDs be restricted during certain critical phases of flight."
This study says we cannot be sure that PEDs are safe. The original comment, that "there are many recorded incidents of interference [which] happened, and were documented by the FAA", is false. There is a slight potential for interference and we hypothesise that this interference could be unsafe.
Look at how metal forks are treated. Compare that with your laptop or smartphone. Spot the difference?
If there was even the slightest chance that electronic devices could materially interfere with commercial flights, taking electronic devices onto a plane and using them would be forbidden. Pretty simple really.
I don't think anyone is against doing something that could potentially save lives -- but I've never seen any evidence to support the current status quo and the number of these types of articles is growing. If there were credible proof of disturbance why isn't it being brought out to counter this debate? This is too big a potential PR problem for the FAA to not try to convince us they're just looking out for our best interests.
The article noted that people ignore the rules all the time. Even if they didn't, devices would be left on accidentally, and devices in luggage will get left or turned on accidentally.
If there's any measurable risk from consumer electronics, instead of "Please make sure all your electronic devices are turned off," the announcement should be, "Please make sure all your electronic devices are turned off, and pray that everyone else does too, pray that no devices are accidentally turned on or left on, and pray that stray rf bursts from ground transmitters don't cause the plane to crash either."
The mandate for everyone to turn off their electronics (and pray) is the equivalent of the industry and the FAA burying their heads in the sand. It reduces the risk, but if that risk was measurable and unacceptable to begin with, it's still measurable and still unacceptable, and the planes' electronic shielding needs to be improved.
It's that simple - if any customer electronic devicea disturbance is messing with some airplane systems, then taht airplane should be grounded forever. Full stop.
It may well be that cellphones present no danger to airliners, but I have had two occasions when forgetting to turn off a cellphone produced interference noise in my headset while flying a C172SP. Of course it was my own cellphone so I just turned it off.
Maybe it's not a problem on airliners because they are better shielded, or just bigger, than a Skyhawk. But I can say first-hand that it is at least possible for a cellphone to interfere with an aviation radio.
I've experienced noise from old phones on cheap computer speakers, alarm clock radios, and installed sound systems in churches. It's annoying, but if the interference is in the audible frequency range, I doubt it's harmful.
Incidents involving interference from GPS, cell phones, etc. are recorded. The way people react when reading those reports is more interesting to me than the reports themselves. It's interesting how strong opinions are on this subject.
GPS devices are completely passive; how can they interfere?
(Unless you are talking about incoming GPS satellite signal. In which case -- dah, they've been out there for the last 40 years, the planes farrady cage structure should have accommodated this long ago, and it can be solved with strategically placed tin foil on the offending openings)
(Unless you are talking about incoming GPS satellite signal. In which case -- dah, they've been out there for the last 40 years, the planes farrady cage structure should have accommodated this long ago, and it can be solved with strategically placed tin foil on the offending openings)
Interesting bit of trivia: the energy received from a GPS satellite is said to be roughly equivalent to a 40-watt light bulb on the other side of the continental US.
That's neat, and I was aware of the theory, not of the practice.
Is there any reason to believe that a GPS unintentionally radiates more than (say) a walkman that has a radio? or a wristwatch that has a built in radio? Or that it should interfere with plane instruments more than the latter?
I'm not automatically discarding any report of interference, but I suspect a placebo effect is in play here, with people paying 10 times more attention to everything when they expect something should go wrong.
I switched from EE to CS quite early (and then from CS to solo bootstrapped startup), so I can only speculate beyond what I've already posted. I'm inclined to agree with you, though; if TV fiction is the infallible source of knowledge it purports itself to be, then pilots would seem to be among the most suspicious of professions (gremlins?).
I'd like to know what makes avionics so special if it turns out that they are indeed very sensitive. Consumer, automotive, and industrial equipment has to shield against, filter out, and isolate all kinds of noise.
The first Bluetooth development kits from Ericsson came with a lot of documentation including papers on how passenger's electronic equipment on planes affected the navigation equipment. The summary was that there was enough redundancy across the different systems that pilots could cope with any problems during level flight but stuff really needed to be turned off during takeoff and landing.
Maybe laptops (and planes) are much better than they were then, but I am amazed by the number of people who have persuaded themselves that there couldn't possibly be a problem so it is ok to ignore instructions to turn off their toys.
That link is down for me right now, but if they really do claim that they're getting interference from GPS then that site is sufficiently unhinged that I can't trust their analysis.
I figure that the way this works is something like this
* Flight instruments will have problems occasionally.
* People on planes always use electronic devices, but the flight crew here about it unless they specifically ask the stewardesses to look for people using electronic devices.
* The flight crew will ask the stewardesses to look if and only if there is interference.
Which means that if the flight crew are normal humans who have heard rumors that these devices cause interference, they will quickly be able to assemble what they regard as evidence for that view.
No offense, but this is what I meant when I mentioned that it fascinates me the way people react. You had a pretty extensive reaction and you didn't even GET to the site, you simply heard about its existence and formed an extensive opinion. FYI: it's run by NASA and collects safety incident reports from pilots and flight crew, air traffic controllers, mechanics, and so on.
Reports have at times been as detailed as reporting that crew determined that a passenger's device caused interference with navigation equipment by observing the effect of repeatedly powering the device on and off. This isn't what the site is for, it's more generally about safety incidents.
The interesting thing about this to me is that it's not exactly inexplicable for devices to emit RF radiation when they shouldn't, or for equipment to not be shielded as well as it should, but engineering-minded people are often inclined to treat this like someone sighted a flying saucer.
edit: if that seems too much like an attack, I can tell you that I thought the whole thing was idiotic until I started digging into the reports and occasionally talking to people about the issue.
Incidents involving interference from GPS, cell phones, etc. are recorded.... by people whose pilot education did not qualify them to diagnose RF communications issues.
radio or speaker wire ? Lots of things cause interference with signals in speaker wire, at short distances (<10 feet, which is only relevant to aviation in the cockpit)
There's absolutely no requirement or testing that says your portable device can't interfere with an ILS. Landing on instruments in zero visibility with untested consumer electronics that don't conform to aviation specs is a bad idea. Maybe it's time to change the regs so anything that can go on a plane has to be tested and regulated to not interfere with aircraft navigation.
When PCs came out, they interfered with TV. There's a set of standards for consumer equipment, eg won't interfere with your neighbor's TV, and a set of standards for aviation, eg won't interfere with an instrument landing system etc. And even if in the current crop of digital devices, it's a low-percentage problem, new devices get invented all the time, with new power and frequency profiles. There is so much change that eventually something is guaranteed to interfere.
In any event, the reg about no cell phones on during flight (as opposed to no electronics during takeoff and landing), is an FCC reg, not an FAA reg, to help out the cell phone companies not having to deal with fast-moving cell phones on max power talking to all their towers at once.
I haven't seen any studies that guarantee the safety of wearing cotton clothing or rubber shoes, both of which have vague effects on electromagnetism as well. Not having any evidence that it's unsafe is good enough in my book. We've had a couple of decades and millions of flights where passengers forgot/ignored/didn't understand the rules without causing a single incident.
Why ignore the evidence? Electronics are not being turned off, which means thousands of flights per day have been made for years with electronics on. Apparently there has been no incident serious enough to up the risk beyond "not guaranteed to be safe". Could you possibly fund a more extensive test of the danger than what is already happening?
The public should be asked if they want to waste many billions, if not hundreds of billions of dollars in lost work to mitigate this "risk".
Frankly, nearly anything is possible if you're accounting for the unknown, like you seem to be doing. Perhaps we should also ban prayer – after all, there may be a god, right?
The other irritating thing about the ban is that no distinction is made between devices that transmit RF and those that do not. Granted, there are fewer and fewer devices that one is likely to carry and use on a plane that are not capable of transmitting something (e.g. wifi or bluetooth), but iPods were banned during takeoff even before they had wifi, and AFAIK portable CD players and tape players were never allowed either. It actually makes more sense now to ban everything because enforcing that they were all in airplane mode would be impossible, but 10 years ago the ban was universally applied to electronic devices and not only radio-transmitting devices.
Mostly I just want to be able to use my Kindle during takeoff and landing. Maybe it will happen:
>"but iPods were banned during takeoff even before they had wifi, and AFAIK portable CD players and tape players were never allowed either."
Someone can correct me if I'm wrong, but I believe the ban on music players during take-off/landing is to ensure that the passenger can hear instructions from the flight crew.
As for phones, well, I don't shut mine off, either.
Also, a blanket ban during takeoff (seriously, it doesn't take that long!) avoids arguments with cabin crew about whether or not your device has wifi or not. Are cabin crew really supposed to keep current on all models of new personal electronic devices?
First, the ban is not just "during takeoff". It's actually from the time the pilot leaves the gate, until well into the air. If there's any delay getting on the runway, it's easily 45 minutes or longer, and the usual wait is closer to 20 minutes.
Both ends of the flight. On short flights, you'll spend more times without your smartphone on then you will with it.
For my ad-supported kindle, even when it's "off" it's still on. I almost never actually hold down the button to turn it all the way off, it's just displaying an ad.
What's really sad about this whole fiasco is how many people take the word of the authorities at face value without spending some time to consider that they might be wrong (as they have been about various things over and over in the past). In this day and age, finding accurate information about almost anything is just a matter of spending a few minutes on the internet.
Same goes for the TSA, which a vanishingly small number of Americans realize is nothing more than security theater and an enormous government jobs program.
You do realise that EVERY country has a TSA equivalent with almost exactly the same policies and procedures. And yes some of it is security theatre but most of it isn't.
This doesn't agree with my experience at all. I've had flights in the US, England, Spain, Bahrain, the UAE, Japan, and China, and the US is by far the most invasive and tedious.
I think it's unique to the US that you need to take off your shoes, thoroughly empty all your pockets and take off your belt, get scanned by the new RapiScan things, and throw away your bottles of water (well, I've experienced that in some of the other countries, but not all).
I'm curious what other people's experience are like. Taligent's comment caught me by surprise because my international airport experience has almost invariably ended with, "wow, that was refreshingly painless. I wish the US was still like this".
My experience was the same. I flew in India, China, Australia and UK last year, and I didn't have to take off my shoes or worry about liquids (except they would so secondary screening for liquids in the boarding areas on US bound flights).
US however was the only place where I could leave my 11" Air in the bag.
I live in Spain and do domestic flights quite a lot (although, high-speed rail is looking better for me every day… 2h30 from city center to city center vs a 1h20 flight plus the train from and to the city, rail is sometimes better), and I always follow the same procedure: take off my watch, empty my pockets, remove my belt, get the tablet/laptop out and put everything in a tray with my backpack on top of it.
I've been asked several times to remove my shoes when those shoes were 'high' shoes, ie. covering a bit over the ankle. Now every time I fly I make sure to have the right shoes, and start removing stuff before arriving at the checkpoint. It does't take long to get past security (I've done under 5 minutes), but still I have to get half-naked and often checked. And it's annoying. HSR (and leaving the VIP lounge, already included in the ticket which has a very reasonable price, ten minutes before the train leaves) is so much better. And just walking past security without having to get half-naked, that too (get your bag through the X-Ray to see if you're carrying something huge and dangerous and that's it).
Millions and millions of passengers are screened every year and so of course there are going to be lots of stories about airport security making mistakes. What you need to show is actual statistical evidence which I haven't seen any to date.
And of course it isn't just theatre. In 2011 over 1000 guns were confiscated by TSA and I am sure everyone can agree that guns do not belong on a plane.
You've left out vital context: how many guns were confiscated in 1999 or 2000, before the new security procedures? Also, of the guns confiscated at airports, how many were detected because we took our shoes off, gave up liquids, or had an electronic strip search performed?
Mobile phones are an old technology. They've had a few different types of technology.
It's trivially easy to see analogue mobile telephones disrupting a wide variety of electronics. Luckily, no one uses analogue phones anymore. It's trivially easy to get a GSM phone to disrupt other electronics. (The burbling noise you hear over a nearby radio when the phone connects to the cell tower is one example.)
Airline safety is conservative. Very many people travel by plane. (Over 133 million just in London each year.)
Being conservative is probably a good thing.
But how are the rules supposed to change? Given that many people think these rules are nonsense, how should the regulatory bodies test phones on planes?
The strength (and capability to interfere) of EM radiation is subject to the inverse-square law. You would cook yourself long before your phone could put out enough juice to interfere with the cockpit.
If you can disrupt a speaker's magnetic field by placing a phone 3 inches from it, then you would need 16,000 times as much power to perform the same disruption from 10 feet away.
If every passenger in a 149-seat Boeing 737 had a cell phone, and you daisy-chained them all together to produce an EM pulse, you could improve your disruption distance to 3 feet without anything in between your output and the target to disrupt.
I wouldn't mind seeing the rule overturned for general usage or data. But I hope that voice calling continues to be prohibited. Sitting on a 6 hour flight listening to multiple people screaming into their phones over the sound of the engines would suck so bad. Its bad enough on a 15 minute bus ride.
Have a space by all means where people can talk, just make sure it's soundproof. I had someone sitting next to me on an hour long train ride, who, if she said "at end o' day" one more time, I would have killed her and pleaded justifiable homicide.
Its interesting that its the same logic as people claiming premonition type events.
So, you're sat there thinking about some one and the phone rings and its that person. Some people say that is such a huge coincidence that it must prove some sort of premonition. The counter argument is that you don't think of all the times it doesn't happen.
So, the "proof" of a connection between mobile phones and airline systems is very similar to the proof people use for premonition. Same argument to disprove it.
Forget the radio interference, put hard projectiles like laptops and tablets away during take-off and landings so they don't go flying around the cabin if there is an incident.
That logic doesn't make any sense, since you can have other hard projectiles, such as a saxophone or a textbook during those times. They'll have to tell everyone to put away ALL objects, which they don't.
A musical instrument would have to be stowed under the seat. A book, though, represents a pretty big loophole. I've never been asked to put a book away during takeoff or landing, even a textbook that's heavy enough to serve as a murder weapon.
There are also way more laptops and tablets around on planes than big heavy textbooks. People tend to bring smaller softcovers when they travel for obvious reasons.
> Forget the radio interference, put hard projectiles like laptops and tablets away during take-off
And the government is what? shy? or embarrassed to admit such physics facts? But in turn had to make up lies and fake convoluted reasons to accomplish this?
You are basically implying that they all gathered in a dark room someplace at FAA and decided "Aha, we don't want all these projectiles flying around, but we don't want to reveal our true motives, so we'll ... call it electronic interference and tell them to stow away electronic devices, but now, everyone must keep this secret!", then they all raise their right hand, swear on their mother's grave, and there you have it, a new FAA rule.
A few things I think the article either left out or didn't consider:
1. It discusses the odds that somebody on the plain has their phone on. As someone who frequently flies with his phone on, I can attest I have yet to die in a plane crash. However, it doesn't necessarily follow that a relatively small number of us rule breakers imply complete safety if the rule is removed. I'd be willing to bet that there hasn't been a flight where every single person had their phone on let alone with airplane mode off. I don't think even this would be an issue on modern planes but it's still silly to claim "a few phones is okay" to "a few hundred phones is okay" without further connecting evidence.
2. In today's terrorist-focused air world it seems implausible that the rule would be handled so casually, especially given criticism of the rule, when they would likely be insistent about this potential terrorist weapon. The prototypical terrorist specter that modern security theater seems so concerned with would love nothing better than a magic electronic box that could take down a plane as easily as some suggest.
3. The focus on safety as the cause seems to ignore other effects. In particular they've created a system that handily avoids people talking loudly on their cell phones for the entire flight. I would not be surprised if they'd keep the rule in the face of conclusive proof on the safety of cell phones just because of this effect.
If they actually have any intention of having people follow this rule, they need to actually start punishing people who blatantly ignore the rules. I've sat on many planes and watched people be told to shut off their iPods... only to turn off the screen until the stewardess walks away, then immediately re-activate it. If people were fined, I doubt the rule would be broken as much.
If, on the other hand, there is no intention to actually enforce this rule, get rid of the damn thing.
And it's not just about devices themselves, it's about being alert. Other rules also require to have the window shades up so you can see what is happening overwing when taking off or landing, for example.
Having a phone on, or let's say, an iPod, won't disturb at all the electronic systems on board of the airplane. Maybe if you're flying a small airplane you'll have a phone doing weird stuff to your headset as someone said below (my personal experience is that it only happens when the phone starts transmitting with more power after you lose cell coverage). Or perhaps if it's a very old plane. But not a really big deal.
But when accidents do happen, you'd better be ready, and one of the reasons the FAA hasn't removed this rule yet, is that it forces most users to actually mind about what's happening (during t/o and landing) instead of being looking at their phones or listening to music. In case of an accident, or if an evacuation takes place, everything would happen in under two minutes and it is usually a good thing to have people see by themselves what's happening and ready to listen for instructions (and not disorientated).
Of course your plane won't crash if you're playing Angry Birds during landing. It's just not a good idea to do it.
Except electronics aren't the only means of distraction, and not all electronic devices are especially distracting.
You can be asleep (I tend to fall asleep before takeoff). You can drink quite a bit of alcohol in the airport and on the plane. You can take a Xanax. You can be deeply into a sudoku puzzle, a book, or a conversation. You can even wear earplugs and an eye mask!
I'm pretty sure my attentions can turn to the emergency at-hand just as quickly if I'm playing Angry Birds or I'm reading a magazine.
* Other rules also require to have the window shades up so you can see what is happening overwing when taking off or landing, for example.*
This is more for emergency crews - if there is an accident, it allows them to see into the aircraft to see what's going on. Passengers being on the inside can already lift the shades as required.
Yet you're still allowed to read a big old heavy book (which can easily become FOD itself), or sleep through take off and landing. People aren't alert during those activities.
Personally, I'm skeptical that cell phones materially affect plane electronics, but the WSJ's argument is laughably thin and illogical.
They show that people leave their phones on. But they didn't measure whether there was interference with plane electronics on those flights. They simply state that all these phones didn't affect navigation systems, with no evidence whatsoever.
It's always disappointing when someone makes a bad case for what is probably a good cause.
I remember reading here during an earlier discussion that the ban on electronic devices had less to do with interference and more about safety in case of emergencies.
During takeoff and landing are when most accidents happen and if people have cables from earphones/laptops, are listening to music or are on their phone, it would be considerable harder for the flight crew to get the attention of the passengers and direct them.
I remember this same topic being addressed in an earlier discussion too. When the "fasten your seatbelt" lights are on, for example during turbulences, electronic devices should be off too, mostly because you may need to be in a state of alertness rather than playing a game.
Why don't they test it? I find it very disturbing that they would continue a policy without data, except for the small point that it's not that big of a deal. I'm only slightly inconvenienced that I have to turn my Kindle off on take-off and landing.
But it really does blow my mind that they are not subjecting cockpit instrumentation to emf interference and seeing what happens. This used to be a big part of military research- shielding and such- so why not?
I would expect to see something like 'signal strengths above WW dBm in the cockpit reduce the reliability of XX readings by Y% causing an unacceptable error in ZZZ. This can be achieved with N devices transmitting within a distance of R meters. Therefore, we require these devices to be turned off.
I find it dumbfounding that people aren't doing/haven't done this.
I didn't read that as meaning systematic testing. I really mean: test with transmitters of variable frequencies in cockpits or mock-cockpits. Measure induced emf in the circuits. Record instrument errors.
They could even require a certain spec on the manufacturers (akin to mil-spec on military grade computers, for example). Much like somebody else said: shielding.
My anecdotes are as follows: In my fathers car back in the early 90's, right before the phone rang the speedometer and rpm meter went nuts. Since that was happening only during some sort of negotiation phase between the mobile and the tower and then stopped, I waited a few seconds and the interference stopped.
Regarding the projectile flying, that is not a small problem and it doesn't happen only during take of and landing. There is a reason they tell you to remain buckled up at all times when seated. During a flight, just as I had unbuckled my seat belt, a turbulence made the airplane fall about 40cm and I landed on my seat's armrest, which hurt.
Mobile phones absolutely do interfere with aeroplane systems. You know how your radio goes dit dit-dit dit when you change cell towers or receive a message? Happens with aircraft radios too. Extremely annoying when your passenger ignores your request to turn off their phone. VOR, ADF, NDB and ILS also all use radio waves and could therefore also be subject to interference.
Any other measurable factor that can conceivably have an impact on a flight has an instrument, or many, devoted to it. If mobile phones were of any risk whatsoever, there'd be a flashing light in the cockpit if something on board was radiating on a phone frequency. The cabin crew would then sweep the cabin with a detector to find the offending person. Instead, they rely on a visual search of items the passengers have in their hands only!
The fact is that there are two parties with real skin in this game - the manufacturers and the airlines. It's those parties whose are motivated and empowered to evaluate the actual risk of EM emissions on a flight, and to take concrete actions to mitigate the risk if the if the danger proved genuine.
In over 20 years since the general availability of mobile phones neither of these parties have taken these actions, or made any sign of needing or wanting to do so, and IMO that says all you need to know about the for-show-only nature of these rules.