[TexasGator]

“You are correct. Musk’s sub would be tugged through a tight channel is such a way as to rip on the rough surfaces. Water would quickly flow in and its precious cargo would silently drown without anyone realizing what happened.”

And your expertise in cave diving, submarines and rescue is?

[jonrick46]

I saw a version of the "rescue sub" which was a type of long bag that looked like a body bag you would use for a corpse. It was to be tief to a rope and pulled along. I've been in caves and their walls are not smooth. I've hit my head on their low head-space. That craft would have snagged and it is unpredictable if would have held together.

Below is the actual craft. Because of its length and rigid construction, I would expect a dry run to see if it would go through those tight passages. Did they have the time for such a test?