[C210N]

Didn’t Even Have a Basic Safety Beacon...

The most SOLID thing about this whole story is that it was enclosed with 17 (Seventeen) Bolts.

The people lost in the missing Titan submersible are dead-bolted in with at least 17 bolts and have no way out unless they're found

[fidelis]

The people lost in the missing Titan submersible are dead-bolted in with at least 17 bolts and have no way out unless they're found

At the depth they were going, a hatch openable from the inside would have done them no good. Maybe if they made it to the surface it would have helped, of course.