Originally Posted by
eng3
Do these bags seal when shut? Wouldn't the bag eventually explode depending on the size of the fire? We fly commercial UAVs at work (Part 107) with large batteries. We use a metal box that isn't air tight (similar to an old ammo box). The thought is that the flames would be mostly contained but the smoke would vent out. Ofcouse smoke is alot more of a hazard on a plane than in a building.
Also, I've always been curious, I understand why they need to be removed if the bag is being checked but why do batteries need to be removed from smart bags in the cabin? Shouldn't batteries be removed from non-smart bags too? I figure it is safer to have them near the passenger where it is easier to notice if smoke/flames start coming out.
Air tight wouldn't help .. Li-Ion battery fires generate their own oxygen via chemical reaction. The only - only - thing you can do to extinguish a Li-Ion battery fire is to cool it ... everything else won't work. All the onboard fire extinguishers do is knock down the flames - hopefully enough to be able to grab the battery (with gloves on) and get it into the bag. Then you have to let the chemical reaction burn itself out. That's really what the pouch does - gives it a place to burn without catching other things on fire.
As for removing from smart bags ... In the early days of so-called smart bags, some genius at a bag manufacturer (starts with A, ends with WAY) decided it'd be a good idea to use screws to install the batteries, rather than make them easily removable.
So in the event it caught fire, well, no way to put it in a fire bag, and the fire is now spreading to the entire suitcase.... Very Bad Day for everyone involved. To the point where I could see a fatal event happening.
That's the thing -- if it's in the suitcase, but "portable" - can be grabbed and put into the fire bag. But if it's screwed in ... bad day.
edit: I'm probably being unfair to the brain-dead designer at the aforementioned bag manufacturer. I know for sure they had non-removable batteries, but I'd guess there were other brain-dead designers at other bag makers making the same brain-dead decision.