Me too. I fly a lot, and the thought of a damaged battery, or somebody leaving their notebook in sleep mode, packed in a suitcase of flammable clothes with all of the other luggage gives me anxiety at times.
If I have both laptops with me, I check the heavier one, but take the battery out and carry it on.
I fly from Hong Kong to the US quite a bit (16 hours), so alternate landing sites are few and far between. That, and everyone seems to be carrying a Samsung Galaxy or iPhone from HK.
Clearly not. Mac users are used to their laptops actually going to sleep when they shut the lid.
My work HP, however, is regularly scorching hot when I get home as it's been on in my backpack the whole time despite me shutting the lid and despite the instruction to 'go to sleep when the lid is closed'. How there's not some sort of thermal cutoff I do not know, but I know for a fact that there is not.
Edit: by 'regularly' I mean a few times a year. Still far, far too many.
If this is not caused by the Windows issue mentioned by TeMPOraL, I might have another explanation:
My former notebook (Acer Timeline 1810TZ) used to wake up from a press on any keyboard button, which I was unable to change.
The issue here is that with sufficient pressure (e.g. when I was running with the device in a messenger bag), the lid would bend enough to actually press a key and wake up the machine.
My hackish solution was a script that would automatically put the laptop back to sleep a few seconds after waking up, which I then manually killed after intentionally waking the device.
It may not be the fault of HP per se. Windows itself tended to cause this on every laptop I ever used by randomly deciding it needs to wake up the machine and check for updates.
AFAIK pretty much all Intel CPUs do have a thermal cutoff, and I expect AMDs do as well.
Unfortunately, it's close to 100 degrees. It's only there to prevent damage to the CPU, not the rest of the system (or your back). It also isn't guaranteed to shut down the laptop, just the CPU.
So it really depends on how well the motherboard manufacturer did their job.
That and I have lived in SE Asia where there's a lot of handcrafted fabrics, foods, and other unbelievable things checked-in and carried on luggage once you're flying on a plane not bound for a major city. Just look at the Customs line in JFK or Newark to see what they pull out of people's luggage if you're coming from Asia or Africa. I can't speak to other points of origin.
I don't know of any reports of fires in luggage holds.
I know there are fire suppression devices as mandated by the FAA. It used to be just containment, but they changed it to suppression thank goodness.
Nonetheless, I vote for carry-on where you can see it before a single-point failure occurs with the fire suppression system unseen in the luggage hold. I can imagine the fire suppression system either not being charged or armed from my related experience with safety issues in the hospitality industry.
Your comment was after mine above. Never? I wouldn't rush judgement. Here is an incident of a lithium battery in a camera bag in an overhead bin causing a fire and subsequent return to departure airport [1], and another of an air-purifier exploding in the cabin causing burns to one passenger and hospitalization of some others due to smoke inhalation [2].
And here's one where the crew of a UPS cargo plane lost their lives due to a fire with rigin located near a pallet containing some lithium batteries in the main deck cargo area. Granted fire suppression was not there I think, but you get the picture [3].
I have not worked in the airline industry, but the above incidents were reported, and were highly-visible, occurring in the passenger cabin. I wonder if there are any unreported incidents of the fire suppression system going off in the cargo/baggage hold? I'll have to read through the source material more.
I know it's speculative, but I say it having worked in a high-risk job where minor incidents like paper cuts and stapler accidents were reported by the front office, but much more serious incidents occurred in the underwater work we did, and did not get duly reported. Safety is a diligence game, and we tend to get jaded by daily 'minor' incidents until a big one occurs and rattles everyone to muster, or it sees the light of the press & public.
If I have both laptops with me, I check the heavier one, but take the battery out and carry it on.
I fly from Hong Kong to the US quite a bit (16 hours), so alternate landing sites are few and far between. That, and everyone seems to be carrying a Samsung Galaxy or iPhone from HK.