Why a plane turned around when a passenger lost a phone midflight

I suspect there’s more swelling that we don’t hear about. Environment matters though. Phones and tablets with wide operating ranges (Samsung was rated for like 0-120 F) have higher failure rates outdoors than iPhones… but if you try to use iPhones in a hot parking lot in the summer or keep them in an outer pocket in the winter, they’ll shut down. (The device doesn’t break, but it fails for the user)

For laptops the target was 4 year replacement for most and 2 year for high performance. IIRC, there was a Dell model where the swelling and battery shape was such that the device was super wobbly and damaged that spiked the numbers. Most devices would just get tagged as a bad battery and repaired or replaced.

If I was still there or in that role, I’d collect more battery data in general, as it’s both an employee safety and perhaps a quantitative difference that can be leveraged in purchasing.

Most people get off with it, but after I found an old iPhone with a badly swollen battery (and put it in my fireplace; this was during the summer until I could properly dispose of it), I became much more cautious about keeping old laptops and the like hanging around the house for old time's sake.

I know I have some truly ancient stuff up in the attic for basically nostalgia and I should just recycle.

This rule only applies to loose (spare) Li-ion batteries, not batteries which are installed in a device.

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.

Interesting, at the airport I always see general "no (devices with) batteries in checked luggage" signs.

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...

Notably the 16” MacBook Pro (every model since 2019) goes right up to the 100 Wh limit.

I also thought the reason you couldn't travel with unattached spare batteries was because something could bridge the + and - and create fire from a short, not because they were lithium. Like, traveling with my little power bank wasn't an issue because it's all enclosed.

many laptops are reaching 100wh limit, dell xps 16 has 99.9wh iirc

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

(100Wh / 3.7V ~= 27000 mAh, 160Wh / 3.7V ~= 43000 mAh. Wh represents theoretical total energy, used as a normalized comparison, and Ah is used to practically determine max safe charge/discharge rates)

When people say “Lithium batteries” in this context, they mean lithium-ion rechargeable batteries.

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.

AirTags also don’t use rechargeable lithium batteries.

Checked baggage is actually one of the better use cases for AirTags.

A phone not in airplane mode and a high capacity lithium battery are not comparable at all.

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.

Small Li-ion batteries installed in a device are allowed in check luggage.

Loose/spare Li-ion batteries that are not installed in a device, and large batteries over 100-160 Wh are banned in checked luggage.

Before you accept your plane tickets you get asked question about illegal hazards you are flying with. Lithium batteries are clearly noted. Maybe you are just skipping that notice because you assume you are not a hazard? :)

This definitely happens stateside. Usually during check-in

I see a warning about rechargeable batteries in checked in luggage almost every time I check into a flight. I wonder what explains our difference of experiences. Maybe it's the fact that I mostly do electronic checkins vs just showing up at luggage drop off.

I do get pulled aside for "enhanced screening" consistently while transiting Europe :-)

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.

United at least seems to make this announcement on a routine basis.

And this is reason why "Ah" unit is stupid and meaningless

Heat a lithium secondary cell too much and it goes into runaway. When the cells are packed together in one device if one of them goes up it can take the others with it. The bigger the device the hotter it will be and harder to avoid it turning into a disaster.

Unfortunately airlines often have more strict rules. Lufthansa says 20 max for example

https://www.lufthansa.com/us/en/prepare-for-your-trip/baggag...

Although 20 loose batteries is still plenty. The real challenge is the 15 devices per person limit

Do AirPods count as 3 devices because charging case + 2 ear pieces?

As a private person, international transport of devices with batteries is a pain.

The order of doing things while flying…

Arranging a reroute with ATC, explaining everything, adjusting the autopilot for the new route etc. Assessment time on what to do. Those in the back don’t need to know anything until those decisions are made and executed. It’s not like there’s a negotiation to be had!

There's always a long list of checklists and calculations to run though. It's rare for a plane with an emergency to land as soon as possible, they generally need a little extra time to finish such tasks.

Based on how many ATC recordings I've heard where an aircraft declares an emergency, diverts, then asks ATC for a holding pattern/delay vectors to set up the landing, I consider this plausible.

They need to find, read, understand and brief the approach charts, missed approach procedures, etc., configure that all in the onboard computer, go over a stack of checklists, etc.

You are helpless, the cabin crew know what’s going on but aren’t telling you, and the hysteria at the back of the plane won’t be alleviated by telling them there’s a fire in the cabin, you’re making an emergency landing and to prepare for an emergency response unit upon landing.

There’s nothing you can do other than stay in your seat and keep out of the way.

Because passengers panic, and that makes the job of the crew harder?

> Why would you not say "we are returning due to a battery fire. The fire has been contained but we must return because X y z" or whatever.

Because as soon as you mention "fire" you'll get a bunch of dumb fucks panicking themselves so hard they're going to behave completely irrationally (like attempting to rip open the emergency doors which IS possible at low enough altitudes) - or manage to induce legitimate medical problems. Heart attack for the older folks, dyspnea up to actually going unconscious from hyperventilation for the younger folks.

The issue is how quickly they cycle the full cabin air volume.

Still I've never heard a pilot communicate like that. On the European airlines I've flown on the pilot would concisely and professionally explain the situation and then make a formal apology.

Seems like a “lithium fire box” or perhaps fireproof bag capable of containing lithium fires and smothering them would become standard on planes. Most personal electronics are fairly small as well.

That isn't the point I was making. Read again.

Turkish Airlines did exactly that (partially disassemble the seat) on a flight I've been on a little while ago. (Someone lost their phone in a business class seat.)

The risks seem to be lower than the ones associated with landing with a device stuck somewhere.

What I don't understand is why they don't construct the seats for less chances of things getting lost in them. Some seats have huge holes to lose things in…

Legal departments advise management, management decides.

In this case, if the legal department paints pictures of doom, and the ops department paints pictures of cost savings, it's up in the air (pun intended) which management will pick.

A competent legal department will provide a realistic assessment of risk to go into this decision making process, not just obstruct everything.

Paper tickets, yes. Paper boarding passes, no. Replacing a paper boarding pass has been easy since airlines switched to an electronic ticketing system where the actual ticket is an entry in the airline's database.

"upgrade me to business class or I won't remember where my phone is as we'll have to go back"