[cyberax]

Unless you're over deep enough ocean to be crushed.

[brippalcharrid]

I don't know what's worse: a gradual realisation that there's going to be nothing that anyone can do to prevent your sudden, violent death or a gradual realisation that you're going to be slowly asphyxiated.

[ranger207]

Especially if your government refuses offers to help https://en.wikipedia.org/wiki/Kursk_submarine_disaster

[LorenPechtel]

Most subs, most oceans, the bottom is far beyond crush depth.