It’s like airplane mode. How many cellphones on a given flight are actually in airplane mode?
Airplane mode is largely pseudoscience/an abundance of caution/solving a different problem than a safety one. There's approximately zero chance of a phone interfering with avionics, especially modern ones, with their very low transmission power.
Supposedly the real reason has always been that mobile network operators don't like the interference high-altitude phones can cause: They're in view of potentially many base stations, some of which might be using the same frequency (which is possible since far-away regular-altitude phones are below the radio horizon and therefore not an issue).
Some evidence for this theory: The "mobile phone ban" is an FCC regulation, not an FAA one, and many (non-US) airlines have been offering on-board microcells for decades without any issues.
That's the steelman version of the parent poster's question.
I'm not saying that current regulations of lithium batteries make sense; my argument is that the actual threat from lithium batteries seems larger than that of devices not in airplane mode (i.e. somewhere around zero).
An uninstalled battery will have its terminals exposed, where they could be accidentally shorted by a stray paperclip, foil wrapper, or zip.
Not in the US, where it applies throughout the flight.
And at least in Europe, the ban is due to the risk of distraction/disorientation in case of an emergency, in my experience.
> the plane is essentially a Faraday cage at altitude, and a phone has almost zero chance of connecting to a tower
Counterpoint: I have a whole collection of “welcome to <place>, your roaming charges will be <exorbitant>” text messages on my phone from countries I’ve only ever overflown at 30k feet.
This is from flights that do permit in-flight phone usage, but I believe my network has no roaming agreement with the microcell operator, so it keeps scanning and sometimes catches a bidirectional link to some long-range tower. (They’re specifically optimized for that in the North Sea and Atlantic for fishing boats, as far as I know, so for regular modern towers it’s probably less likely, but that separation hasn’t always existed.)
[0] https://www.dailymail.co.uk/news/article-6839167/MH370-pilot...
I do agree that interference is quite relevant. The general rule of radio is that you play nice, especially when on a licensed frequency (the cell companies have the licenses for those bands, the users do not), and a phone up high over multiple cell towers is most certainly not playing nice.
Loose/spare Li-ion batteries that are not installed in a device, and large batteries over 100-160 Wh are banned in checked luggage.
"Devices containing lithium metal or lithium ion batteries should be carried in carry-on baggage. Most other consumer electronic devices containing batteries are allowed in carry-on and checked baggage."
Taken literally, this is of course widely ignored. There are also various requirements around spare batteries that do include capacity limits.
Literally never once have I been asked that and I flew internationally 6 times a year for more than 5 years.
The only thing I can think of is maybe something about you makes them think you'd have batteries in your luggage? :)
This definitely happens stateside. Usually during check-in
People who don't care are the reason I don't fly anymore.
I'm sure you didn't actually mean it that way though :-)
A sibling comment made me recheck the rules and it does seem like phones and other small rechargeable devices are allowed in checked baggage.
Maybe I've been unconsciously extending "power banks and rechargeable batteries" to also mean device when questioned.
Except that one time in Latin America where they would only let me put my ultra-compact camera in checked baggage if I took out the batteries.
[0] https://www.faa.gov/hazmat/packsafe/lithium-batteries
[1] https://arstechnica.com/gadgets/2022/10/lufthansa-awkwardly-...
AirTags contain lithium primary batteries, which are a totally different thing (other than both containing the element lithium).
Lithium primary batteries present no more a risk than alkaline AAs. Probably less.
How does that tell you that they are dangerous? The danger with rechargeable Lithium batteries isn't that they contact water and begin to burn.
Lithium poses two risks:
1) The internal resistance is low enough that if it's shorted it can go into thermal runaway. This is the risk they had in mind when saying no loose cells (but note that cells merely need to be securely contained, not specifically in a device.)
2) Secondary cells can grow whiskers inside the cell. If a whisker grows just wrong it can short the cell from inside and drive it into runaway. This is the risk that they are worried about here--and it's a legitimate risk, it's brought a plane down.
The reason the rules are different in the passenger compartment is that while there's nothing on board an airplane that can fight a lithium fire it's generally a small, weak fire (the big e-bike batteries that have been in some rather dramatic videos aren't allowed) that humans can generally keep from turning into a big fire. But if nobody can fight the fire you have a big problem. Hence why lost phones are treated very differently--they could have fallen someplace where the fire wouldn't be fought.
This rule only applies to loose (spare) Li-ion batteries, not batteries which are installed in a device.
Batteries over 160 Wh (in some cases, 100 Wh) are banned whether they’re in a device or not, but that’s far bigger than any phone battery: an iPhone 16 Pro Max battery is about 16 Wh, and typical laptop batteries are around 60 Wh.
IATA Li-ion battery fact sheet: https://www.iata.org/en/iata-repository/pressroom/fact-sheet...
[1] https://en.wikipedia.org/wiki/Orders_of_magnitude_(energy)
Enough energy to heat 1 kg of water by 86°C (or 86 kg of water by 1°C).
The average failure state of a battery is not similar to detonating a handful of TNT on an airplane, which is a more instantaneous explosion. Sure, some battery failure states are violent and would unquestionably be a cause for an airplane to call a mayday and land, but something like puncturing a soft-cell battery is still a slower release than TNT.
We should just expect people to get better at understanding useful units — I'd prefer someone learns Wh since it is indeed a useful metric—kWh is the usual major unit of energy at home, and Wh is just smaller than that.
I've heard of people ordering 18650s online and getting them along with a free flashlight in which they came; I wonder if this regulation is why.
The battery limit described is for individual passengers, not air freight.
Slightly off topic, but she does an amazing job.
Green Dot Aviation: https://www.youtube.com/watch?v=T7uw6VzWHcM
Mentour Pilot: https://www.youtube.com/watch?v=Y50saxfTqQA
And people dont travel with single device anymore. My usually setup has 72wh powerbank, ~20wh phone and 90wh laptop, and various smaller gadget. They are reaching nearly 200wh
One time I had an old phone with battery removed in checked luggage and when I arrived at my destination, I saw they fiddled with the tsa lock and the phone was taken out of the envelope I had it in and just lying on top of my clothes. I mean maybe they saw it in an xray and wanted to steal it and then saw it was some old junk phone, no idea how good the xrays come out to tell beforehand whether you're dealing with an iPhone or 7 year old android midrange...
Maybe not conventional batteries, but you've been disallowed from putting lithium batteries in checked luggage for at least 16 years. I remember being dragged into the bowels of an airport by security to open my checked bag because I'd forgotten a device in it. That was in 2009.
When you check in bags they ask you to make sure there aren't any rechargeable devices or battery packs in them and this has also been going on for a long time.