A few weeks ago I was on a navy submarine. They explained the escape procedure and I asked how survivable it was. Apparently nobody has much faith in it, but its better to try than certain death by drowning.
... I did wonder how painful a fast ascent from the bottom of the ocean would be once the bends kicked in, but had enough sense not to raise this question with about a quarter of the crew in earshot.
The insides of submarines are at roughly 1 BAR. Unless there is a breach of the integrity of the submarine and you manage to stay in a compressed air pocket for a sustained amount of time (unlikely, at best) prior to ascent, you will not have gas disolved into your tissues and thus won't get bent.
That's not how flexible containers work. In the presence of increased pressure, the guts press against the diaphragm, which compresses the lungs.
I don't have to imagine what removing air from my lungs feels like: that is part of breathing! Anyway, this guy seems to do OK compressing his lungs even more:
If the increased pressure is high enough, your diaphragm and lungs are going to be in a world of hurt.
Physiological freaks aside, go too deep, and you're dead. Especially when you go from 1 bar to, say, 15 instantly, which is a situation that free divers do not expose themselves to.
You know that pain you get in your sinuses and ears and other air-pockets in your body when you swim to the bottom of the deep-end of the pool? That's from a pressure difference of like .3 bar. Now imagine something 10 times that.
One would imagine that any escape procedure from a submarine involves some type of airlock and some type of air breathed in at the pressure for whatever depth you are at.. otherwise you'd just be unconscious from the pain instantly.
... I did wonder how painful a fast ascent from the bottom of the ocean would be once the bends kicked in, but had enough sense not to raise this question with about a quarter of the crew in earshot.