Please Turn Off All Electronic Devices…

I’ve always assumed that the requirement to turn off all electronic devices prior to takeoff (and landing), and not to transmit signals inflight, was silly and not based in science. That perhaps if you could pick up cell signals it would be problematic for your providers, hopping around as you are. But that the median electronic device carried by the average business traveler couldn’t possibly interfere with an aircraft’s navigation systems. But as with so many rules, once implemented they’re hard to dislodge.

But I know nothing of the science of these things, and I know little of aircraft systems, so I don’t pontificate (or at least I try to shut my mouth about things I actually don’t know anything about, more or less).

I was most surprised to read this from Through the Lens, a blogging flight attendant:

Did you know that for my little aircraft, when a passenger texts or emails someone on a blackberry, an error message comes up on the screen in the cockpit. I have had the pilots call me right before and right after takeoff to do a walk through to try and find the blackberry that is still on.

Can this be right?

She goes on to justify the total ban on electronics by suggesting it isn’t possible to sort out in the hurry to do all the things required prior to takeoff which devices are safe and which are not. And I’ll be the first to agree that flight attendants are asked to do quite a bit, some for good reason and some for less good reasons. And asking them to ascertain the technical differences between various types of signal-emitting devices probably wouldn’t be a good idea (kinda like asking TSA to understand the chemical properties of batteries, though I have far more respect for flight attendants).

Now, I’m way out of my depths to begin speculating about solutions when I dont’ understand the underlying basis of concern. But certainly if it’s true that there are some devices that would be known as problems and many common devices that wouldn’t be then an easy process could be established to determine which is which. Perhaps companies building devices that are ok to ue inflight could voluntarily adopt a standard ‘green light on top’ that would exempt it from the rule? That particular strategy may not be the answer but surely we could come up with something that would allow me to continue to read off an electronic device while sitting in the penalty box at O’Hare…

Do any of y’all know whether problems really could ensure (and why or why not) from electronic devices below 10,000 feet?  Could they really interfere with tower communications, for instance?

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. I don’t know if it’s true. As an attorney, however, I do know that we have to shut off blackberries and cellular phones during depositions because their electronic signals interfere with the recording equipment used by videographers. In fact, I’ve listened to depositions where attorneys failed to turn off their blackberries and you get some significant interference. So, although it seems implausible, it doesn’t seem impossible, at least to me.

  2. A friend of mine is a pilot with American Airlines. I asked him the same questions – and his answer was that, basically, most airline accidents happen during takeoff and landing. Electronic devices need to be turned off and stowed so that passengers have their full attention during the most crucial of moments.

    I’ve turned my GPS on during a flight, and forgot to turn my cell phone off on multiple occasions (at least 10 times). No planes crashed, and its laughable that an error message would come up in the cockpit. There are so many satellite signals and radio waves criss crossing the skies that a short-range device couldn’t even begin to compete with.

  3. I am skeptical. I am not saying that there isn’t interference, but if there is, then airlines or the FAA should mandate use of a “sniffer” that the flight attendants can use to detect phones and Blackberries in the cabin. They could walk down the aisle and the meter would register when it sniffs something transmitting.

    Also, I would like to see some “proof” of interference. Maybe a YouTube video of someone sending a text message and the error in the cockpit. Some cause and effect video would go a long way to get people to comply if they could see the evidence.

  4. I have had non-rev pilots sitting next to me in the cabin and they have no problem texting away on takeoff and climb-out or landing for that matter.

  5. It’s so people aren’t distracted, can hear what’s going on and heavier items are secured away so they don’t fly around in the case of an abort/incident. The signal interference claim is just to spook people into behaving (because many people are electrically/mechanically unaware and would just believe that it’s for technical reasons).

  6. SMS text messages ride in the control packets of the protocol the phone uses to talk to the tower. There is zero difference in the RF emission of a phone sending a text message versus a phone that is on and stowed.

    A pilot who claims to see an error message when someone texts is full of crap.

  7. My sister’s father-in-law is also a pilot for American and gave me the same response Dave previously provided.

  8. I was once flying a CO 757 into FLL and while on the downwind leg to land, the captain came on the PA and said in a stern voice, “Whoever just turned on their cell phone, TURN IT OFF NOW!”

    I always presumed his announcement was based on something unexpected in the cockpit.

  9. I’ve landed at JFK and everyone turned their phones on (New Yorkers, what can you say?) and the pilot asked everyone to turn them off as they were interfering with his communication with the tower. And yes, we could hear it over the intercom.

    But a flood of phones trying to lock on is a special case, no?

    My special objection is to even turning off a non-phone iPod. WTF?

  10. The rule FAR 91.21 was enacted in 1963. The reason was during a 1961 Washington Redskins football game an airliner was attempting to land at Washington Dulles Airport. Many of the passengers had AM transistor radios and back then they were using ADF navigation to land. One of the main hazards of ADF is electrical effects. Since so many pax were using transistor radios to listen to the Skins game they could not get the ADF indicator to lock onto the station. Hence the new rule.

    However, nowadays it makes absolutely no difference and there have been no confirmed incidents or accidents resulting from cellphones. I have about 3,000 hours combined as pilot and aircrew both military and civilian and I often talk on my cell while flying and or check email with no negative effects. Basically during critical time of flight takeoff and landing that is when you want to be aware so the rule is basically in place for safety reasons.

  11. This is a common misconception. The FAA doesn’t micromanage airlines to the extend that people think they do (same goes for number of carry-ons, bottles in seat pockets, the famous “ATC delay”, etc.). The airlines make these rules (they then have to be approved by the FAA, but the airlines basically propose their own rules).

    The FAA does not regulate the use of electronic devices. You’ll notice that 91.21 allows the use of any device that the operator has deemed safe to use. If anything, the FCC might have something to say about electronic devices – besides 800 Mhz analog cell phones (which nobody uses anymore), they don’t restrict cell phones, though.

    So, in practice, that means that you’re certainly allowed to use any device you wish as long as you (as the operator) has deemed it appropriate to do so. It’s got nothing to do with the FAA or the government. The airlines have simply decided that they don’t want to have passengers use cell phones. They could change their rule anytime they wish. But why would they?

    It’s kind of a moot point because my cell phone never really works for a call above 4000′.

  12. I’ve often wondered why the TSA goes to such efforts to keep guns and shampoo off the aircraft, when (if the airlines are to be believed), all the terrorists need to do to bring the plane down is turn on their cell phones and flush some trash down the toilet.

  13. About 2 years ago I accidentally lefty my cell phone in my checked bag. I realized it a minute or two after it went down some conveyor belt. When I went back they told me there was nothing they could do and they didn’t seem the least bit concerned that it was on. I realized then that it can’t be doing anything to make my plane crash. I could see that if a cell phone was close to a receiver that it might cause some nusance interferrence, as mine sometimes interferres with my clock radio.

    This seems like how it used to be at hospitals, that you couldn’t use a cell phone there because it could interfere with life support, but you never heard of a single case of it. While hospitals haven’t become a haven for cell phone use, you don’t really see signs or anyone enforcing any no cell phone rules there either.

  14. there was MythBusters or the like, which fired tasers into the cockpit dashboard during takeoff & flying. Neither had any extended issue (the screens flickered for a second).

    I feel it’s more about limiting distractions, & getting the passengers to pay attention at the critical points….though I like everyone else tends to read instead.

    I have left my cell phone on, by mistake, or it’s powered itself back on & actually received emails at 15,000′ or such.

    Granted I fear the day, they’re allow cell usage while flying. I still don’t think it has any affect

  15. I’ve been a pilot for nearly 25 years, I can tell you that mobile phones would cause no problem (at least since circa 1990). I would love to hear more specifics about this “screen” that has an “error message”. Flight attendant lying? Never! Old 800mhz cell phones were shown to rarely cause interference. The newer frequencies are fine. There is a law against using mobile phones in the air, but it is an FCC law. It is because line-of-sight from the sky causes you to activate multiple towers at once.

    As for other electronic devices, people have been using their laptops with bluetooth and wifi enabled for years (not knowing how to disable it), and now people are actually allowed to use wifi for real.

  16. My brother is an EE who has been on the design team for a number of systems for Boeing, and although he hasn’t worked in aviation for a while, he assures me that a cell phone can’t possibly interfere with any of the cockpit functions.

  17. Wow, this is a heated debate… quite like those that I have on the aircraft. I didn’t mean to create such a stir. Let me try and clear up a little of this talk. My whole post was meant to be about how I need passengers to comply with turning electronic devices off.

    I did state that I am writing from my personal experiences. I have had my pilots call back and tell me they were getting error messages in the cockpit. After all the negative comments I chatted with my pilot roommates.

    On the plane I fly on (CRJ200) they will get message in the cockpit called EFIS COMP MON that comes up on the primary flight display when
    some information between the captain and first officer do not agree, example heading indicator. A lot of our pilots seem to think this is from cellphones and this is when they call me to do a walkthrough.
    They also can hear interference in the background of the headsets. Usually when the pilots turn off their own cellphones it goes away.

    Sorry for the inital confusion but I wanted to clear up what I wrote. I am not speaking for all aircraft and I am in no way an expert. All I can state are my experiences and knowledge.

    Anyways, my main point was that we are just doing our jobs and need people to comply with what we say. From the likes of the comments, I understand why it is so hard for a lot of people to listen to us. Believe they interfere or not, if we say off, they need to be off- for whatever reason it is.

  18. It’s bogus. As someone else said, it’s just so you pay attention to the FA’s during takeoff and landing.

  19. I recently flew on a UX Flight and heard a similar announcement from a FA.

    However, this announcement was made during landing and something like “My indicator lights show that someone has just turned unbuckled their seat belt. PLEASE turn fasten your seat belt NOW!

    A few second passed and she then said “Thank you as if she knew the seat belt was actually refastened.

    That announcement was the first time I’ve ever heard such a thing and there’s no way I believe she was telling the truth.

    Similar to the original topic of cell phones & other electronic devices, even if there really is scuience to support it, just the fact that SO many people don’t believe it it seems reason enough to abandon it.

    Instead the FA/Pilot should go with the
    more believable position that those devices do distract passengers at a crucial period and it’s in everyone’s best interest that all distractions should be eliminated.

  20. Friendlyskies,

    The ASRS are full of of incidents where pilots/FAs “decided” that pax electronics were causing strange happenings on the aircraft. The real deal is that when there is an anomaly in the cockpit, you could search through all of the pax, and certainly find someone with an electronic device on. Also, when there is no anomaly in the cockpit, you could search through all of the pax, and certainly find someone with an electronic device on. There will always be an electronic device on. That doesn’t make it the cause of an anomaly. It would be akin to saying, “there was a warning light because there was someone with sideburns on the plane”. The human mind will always seek a reason for an anomaly. However, the science shows that it’s not electronic devices that cause the EFIS error you reference.

    As far as following crew member instructions, of course the FAA requires it of all pax. However, when the FA gives reasons for their instructions that are utter nonsense (e.g. electronic device interference, or even more ludicrous: bk3day’s example), it not only causes the crew member instructions to be snickered at, but does not give much confidence to the pax, regarding the “most important safety feature on the aircraft”.

  21. I would have a lot less confidence in the flight crew if when the pilot called back to ask them to make and announcement and do a walk through looking for electronic devices they didn’t. This is my job and I do what’s told of me and I don’t really care what if my passenger snicker or not. I am concerned with landing at my destination safe and sound, if that happens, it was a good flight. It’s good to know all my passengers are aircraft experts and can tell me what is what…

    How about you let me come into your work and I can snicker and tell you what to do. no?

  22. Flying to Denver and back. Flying to Denver and back I was quite surprised to hear the announcement “turn off all electronic devices” before landing. I received a pacemaker last September. On the return trip to Phoenix while leaving the plane I said to one of the plane personnel while leaving the plane . ” I almost died when I turned off my pacemaker, he smiled at me. I said “you dont think I have a pacemaker , do you ?+ as I smailed back. He said “Yes , I really do”
    Henceforth a small addendum “does not apply to pacemakers, artuficial hearts, or other medically implanted devices”

  23. Any electronic device with a high frequency operating clock inherently induces a magnetic field around it, which can, in theory, cause noise in data received from the airplane’s antennae. This occurs because high frequency clocking is essentially a rapidly alternating current, and changing currents create magnetic fields. This is why low speed ICs have pins, whereas CPUs are nowadays ‘ball-pin’, since using traditional pins at the speeds they operate actually creates a sufficient field to interfere with their processing. It is unproven definitively that electronic devices can or have influenced airplane radar/guidance systems/autopilot/tracking, but it is possible in theory. To err on the safe side, passengers are asked to shut down all electronic devices, to prevent this very unlikely occurance.

  24. Felix, the FAA does have regulations prohibiting the use of PEDs (Personal Electronic Devices) aboard US Commercial flights.
    For your reference, with certain exceptions, Title 14 Code of Federal Regulations (14 CFR) parts 91, § 91.21, part 121, § 121.306, part 125 § 125.204, and part 135, § 135.144 prohibit the use of PEDs brought on board the aircraft by any person.

    As a commercial pilot, I can attest to personal experience with cell phones interfering with radio communications with the cockpit and Air Traffic Control. You can hear what we hear by placing your cell phone near your land line phone while using the land line, or near your computer (speakers on), it’s that buzzing sound you hear and sometimes makes understanding ATC instructions impossible.

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