I believe there are USCG certified submersibles… probably nothing close to the depths this thing was capable of diving though. USCG certifications, even on surface boats/ships, historically has been incredibly flawed and noted as prominent factors many tragedies- especially things like passenger unsafe modifications, accurate stability calculations, passenger capacity, etc. That’s not to disparage the coast guard from the many good things they have achieved and continue to advance in terms of safety. There’s so few vehicles that go to these depths, especially for tourism, it does seem like something that would be hard to certify and outside of the USCG wheelhouse, so to speak. I would not be surprised if this changes as a result of this.
It heard on the news that typically this submarine would be scheduled for 5 days at the wreck and every day they would attempt a dive because the submersible was so unreliable 4/5 attempts would fail. I don’t know much about such vehicles, but that doesn’t sound very reliable. The environment these machines must endure is nothing short of extreme, but an 80% failure rate seems unacceptably low, especially for a commercial operation giving site-seeing tours.
I think it is important to remember that the “customers” were likely very aware of the risks involved and seemed to be adventurous people. Deep sea diving is incredibly dangerous. 13,000ft is well below what any (normal) military submarine can handle. A Virginia class submarine test depths (classified info) estimated to be between 1300-2000ft. Even if it’s double that, it’s far from Titanic’s depths. If they are dead, at least they died on an adventure that brought them joy in life. That can’t be said for most people.
I think best case scenario they lost power- but I have to imagine there would be backups for critical communication devices which I have to imagine at a minimum would include some type of sonar beacon. If they are able to stay warm, then they have a chance.
I highly doubt they are floating on the surface somewhere- I’d think they’d be detected by now and surely would have an EPIRB and possibly AIS to indicate their location. I’d think they’d have some ability to deploy dye or have flashing lights to make themselves highly visible to even the naked eye.
More likely, I suspect they suffered some type of hull breach, probably a severe one and have unfortunately died. I’m sure they will be found eventually, just not alive.