For those who are unaware: A couple billionaires, a pilot, and one of the billionaires’ son are currently stuck inside an extremely tiny sub a couple thousand meters under the sea (inside of the sub with the guys above).
They were supposed to dive down to the titanic, but lost connection about halfway down. They’ve been missing for the past 48 hours, and have 2 days until the oxygen in the sub runs out. Do you think they’ll make it?
Decompression sickness is a concern only if they suffered compression. But the main problem, as I see it, is that the sub was made from materials that are famously brittle and tend to degrade over many cycles of pressure and release (resin, carbon fiber, etc). So the likely failure mode is catastrophic failure of the sub under pressure.
There’s a reason most deep sea stuff is made out of steel: it’s somewhat ductile and recovers from compression with minimal change in properties.