It isn't? I'm still confused what else a "sub" could be in this context...
Edit: after reading more it's "submarine", I've spent way too much time on Reddit.
A submarine. You remember the rich maniac who wanted to see the titanic wreck and didn't apply to any safety regulations since it's international water
*submersible
Submersibles, unlike submarines, have to be transported to where they are going to operate by a different vessel.
It isn't? I'm still confused what else a "sub" could be in this context...
Edit: after reading more it's "submarine", I've spent way too much time on Reddit.
A submarine. You remember the rich maniac who wanted to see the titanic wreck and didn't apply to any safety regulations since it's international water
*submersible
Submersibles, unlike submarines, have to be transported to where they are going to operate by a different vessel.