[Retric]

How many cells in a laptop? I would assume 3 at the low end, but it can go much higher and many people have multiple laptops, cellphones etc. So, 20 per person on an aircraft is probably a solid round number.

How many people in an aircraft say ~200. How many aircraft in the air say ~5,000. Now that 10 million is down to 2-3 per however often those 1 in 10 million chance is supposed to stand for.

[simplexion]

Replace aircraft with car and continue this conversation.

[greglindahl]

Cars typically have battery packages that can easily survive a cell failure without anyone noticing.

[evan_]

If your phone battery explodes and starts a fire you have better odds surviving a dive out of your car as opposed to an airplane.

[guax]

You must have a pretty big phone to take down an airplane. If you are driving the car you are much more likely to loose control and cause deaths then a phone bursting in an airplane causing anything more then nasty burns.

[Retric]

Fires in a luggage compartment may be an issue even if they start small.