Titanic tourist submersible goes missing with search under way

[dunmunro]

Titanic tourist submersible goes missing with search under way:

https://www.bbc.com/news/world-us-canada-65953872

[Steve Crandell]

I'm not very hopeful.

First, if they were still alive I would expect them to be making noise; if nothing else banging on something.

Secondly, how can they help them even if they are still alive at that depth?

I'm afraid the only hope is for them to be on the surface somewhere, in which case they should be within radar range of their support vessel.

Someone suggested they might be caught in something. If so, how would you assist them at that depth? I doubt there is another deep dive submersible close enough. One can hope, of course.

[wadinga]

Hi All,

There are muddled (uninformed) references to using radio underwater *, but my understanding is that these deep diving units use acoustic transmission for comms which can struggle at great depth (ie range) and can be be cut off by shadowing by the wreck's hull. Wikipedia https://en.wikipedia.org/wiki/Communica ... submarines says a JANUS acoustic protocol of 2017 can operate over distances of 28km/17miles.

The operations for Cameron's films and subsequent tourist trips used two Russian submersibles, MIR 1 & 2, plus ROV cameras and thus these units could support each other. Despite the ticket price this current commercial operation looks a bit shoestring with all eggs in one basket and ropey comms.

In the fiction Red October they flew in a DSV from elsewhere but this is super-deep. And of course Russian resources are "off limits".

* I know VLF and now Super Low Frequency and Extremely Low Frequency systems exist, but these require massive terrestrial antennas and are surely one way systems and will still not get down to those depths. Plus you need a long antenna on the sub.

With great adventure comes great risk. I hope they can be rescued.

All the best

wadinga

[Steve Crandell]

When I served in submarines in the 70s we had a VLF "football" antenna that could be deployed like any other mast, but it's reception wasn't as good as the floating wire antenna which was trailed out in the ship's wake and was quite long. Neither could be used to transmit. We also had underwater telephone, but it was relatively short range. I don't know how far away it could be used, but we typically were pretty close. Ours was rather low power because we didn't want to be detected by undesirables. In any case for that reason we didn't use it except in exceptional circumstances.

Just some trivia which doesn't really relate to the current situation. I just hope they are bobbing around on the surface somewhere and someone will detect them. You'd think they would be pretty close to the support ship, though.

[marcelo_malara]

Regrettably incident. If they were on the surface for sure they should have an EPIRB (Emergency Position Indicator Radio Beacon), it transmits the emergency to a constellation of satellites, this is relayed to the Earth, and a search & rescue effort is launched, using the signal of the EPIRB for final homing.

Lacking this, I presume they are deep....

Going to those depths is an extremely dangerous adventure, I am not sure that it should be used as a tourist attraction, disclaimer notwithstanding. By the time of the Apollo 17, six missions had landed in the Moon, but only once (I believe) the deepest point in the ocean was reached.

[wadinga]

Hello All,

Having seen a video widely available on the web, this submersible seems IMHO to be an amateurish bodge-job, with only the pressure hull of professional standards. It uses a Playstation controller to run its internal systems. Looking at the sparse external fittings it seems unlikely that devices like EPIRB or a distress acoustic beacon for underwater use were installed and the emergency ballast release system looks extremely primitive. There seems to have been no regulatory inspection of it as a passenger carrying vehicle. Tourist boats have to comply with regulations for saving life at sea, and harbour authorities have the power to impound them for not doing so. Even Titanic fully complied with the Board of Trade regulations in force at the time.

I think this vessel has more in common with the CSS Hunley than other current DSVs. A death-trap, indeed. The wealthy passengers should have had more common sense and employed some professional advisors to evaluate the craft before risking their lives in it. The latest news of sonobuoy pick-up of "banging noises" may be a hopeful sign, but time is running out.

Thanks Steve for your experience input. Location, communications and rescue from submarines operating at conventional depths is still hard enough but this is way deeper and way more difficult.

All the best

wadinga

[Steve Crandell]

I'm actually surprised there hasn't been reports of a destroyer in the search area. Many of them have VD sonars. Also, while their active sonar wouldn't be very useful in finding the DSV, it is very powerful and would serve as a morale boost and encourage more banging from the DSV. It is possible there is an SSN in the area, and the navy might not reveal that to the public.

[marcelo_malara]

Hello All,

Having seen a video widely available on the web, this submersible seems IMHO to be an amateurish bodge-job, with only the pressure hull of professional standards. It uses a Playstation controller to run its internal systems. Looking at the sparse external fittings it seems unlikely that devices like EPIRB or a distress acoustic beacon for underwater use were installed and the emergency ballast release system looks extremely primitive. There seems to have been no regulatory inspection of it as a passenger carrying vehicle. Tourist boats have to comply with regulations for saving life at sea, and harbour authorities have the power to impound them for not doing so. Even Titanic fully complied with the Board of Trade regulations in force at the time.

I think this vessel has more in common with the CSS Hunley than other current DSVs. A death-trap, indeed. The wealthy passengers should have had more common sense and employed some professional advisors to evaluate the craft before risking their lives in it. The latest news of sonobuoy pick-up of "banging noises" may be a hopeful sign, but time is running out.

Thanks Steve for your experience input. Location, communications and rescue from submarines operating at conventional depths is still hard enough but this is way deeper and way more difficult.

All the best

wadinga

Would you post the URL?

Back to the sub, a powerless submarine will go to the surface if it is hydrostatically positive, or the the bottom if it has negative buoyancy. If it was in the surface most probably they would have used VHF or EPIRB, or even a satellite phone. RegrettabIy I presume it is on the bottom.

[marcelo_malara]

Just seen this one:

https://www.youtube.com/watch?v=29co_Hk ... dayMorning

Now I realize that the crew can´t get out without outside help!

[Steve Crandell]

Just seen this one:

https://www.youtube.com/watch?v=29co_Hk ... dayMorning

Now I realize that the crew can´t get out without outside help!

Which probably means they could suffocate on the surface!

[marcelo_malara]

Just seen this one:

https://www.youtube.com/watch?v=29co_Hk ... dayMorning

Now I realize that the crew can´t get out without outside help!

Which probably means they could suffocate on the surface!

Yes, or that the sub is on the surface and the crew can not go out till it is raised onboard. Very poor engineering from any point of view.

[wadinga]

Hi Marcelo,

What I saw was just a slice out of the video you posted. Very comprehensive.

Wikipedia has pulled together a site including the serious misgivings former employees and professional bodies have had about the safety of the vessel.
en.wikipedia.org/wiki/2023_Titan_submersible_incident

Compared with a proper DSV https://en.wikipedia.org/wiki/DSV_Alvin an article which includes recovery after it sank in deep water with no crew aboard, this Titan thing is just a carbon fibre coffin you are bolted into. If you are lucky you might not die. I am very much afraid their luck has run out.

Alvin and mother ship Atlantis are currently in San Diego so no help there.

All the best

wadinga

[marcelo_malara]

Hi Marcelo,

What I saw was just a slice out of the video you posted. Very comprehensive.

Wikipedia has pulled together a site including the serious misgivings former employees and professional bodies have had about the safety of the vessel.
en.wikipedia.org/wiki/2023_Titan_submersible_incident

Compared with a proper DSV https://en.wikipedia.org/wiki/DSV_Alvin an article which includes recovery after it sank in deep water with no crew aboard, this Titan thing is just a carbon fibre coffin you are bolted into. If you are lucky you might not die. I am very much afraid their luck has run out.

Alvin and mother ship Atlantis are currently in San Diego so no help there.

All the best

wadinga

Yes, that´s another suspicious think. Old deep sea vehicles, like the Trieste, were composed of a spherical thick skinned cockpit. As this sphere had negative buoyancy, a positive buoyancy tank was added, filled with a lighter than water component, in Trieste case oil, in more modern vehicles a plastic compound. In the Titan a cylinder is used as the cockpit, not only this is inferior form to resist pressure than the sphere, but it is made of carbon fibre.

[OpanaPointer]

Retired USN here. Banging vigorously when you don't know if someone is actively listening would use up O2 quicker. Would NOT recommend.

[Steve Crandell]

Retired USN here. Banging vigorously when you don't know if someone is actively listening would use up O2 quicker. Would NOT recommend.

Retired USN also. If you DON'T bang, it will probably take them weeks to search the whole area and you will probably suffocate. IIRC recommended is to bang for a minute or so every 30 minutes. That gives a sonar operator a good chance to get a bearing, and if they move then 30 minutes later they can get an approximate location from the second crossed bearing. SSNs are really good at that process and I hope they have one there that they aren't telling us about.