OceanGate Submersible Missing (likely imploded)

[Lord of the Dance]

If you've been following the news lately, you have probably heard about the missing tourist mission near the wreck of the RMS Titanic. OceanGate's 5-person submersible, Titan, went for a descent to the wreck (around 12,600 feet) on Sunday morning and hasn't been seen or heard from since. Aboard the sub were several wealthy passengers (a Pakistani father and son and a British mogul) as well as a Titanic historian and the CEO of OceanGate (I'm presuming in position of pilot of the mission). There's been a massive search and rescue effort put forward with no results as of yet.

As more information comes to light, it would seem that this submersible had serious design and material flaws that weren't properly addressed at conception or even during sea trials. The pressure hulls of most deep-submergence vessels are made of a steel alloy that can flex a bit as the pressure increases with depth. Apparently this submersible was built with a carbon composite hull tube and Titanium endcaps - materials not known for their ductility.

The submersible also appears to have been made with many improvised parts - not an acceptable compromise when undertaking dives in the thousands of feet. As much as I'd like to believe that the occupants are still surviving on life support, it would now seem a likely conclusion that the submersible catastrophically imploded on its descent to the shipwreck below. Given the times involved, I would estimate that the submersible was between 9,000 - 10,500 feet underwater when it failed. Death would have been virtually instantaneous.

It's worth noting that this submersible had made several successful dives to the wreck of the Titanic within the last two years, but pressure loading cycles on the sub's hull likely started to exacerbate small imperfections in the carbon fiber hull and / or the main forward viewport which finally failed on this mission. ABS certification is a costly process which usually involves destructive testing of various components, but it is absolutely worth it when lives are on the line. This guy, Stockton Rush, wanted to push the envelope of submersible innovation with his carbon composite hull, but he paid the ultimate price. What a shame he took these other folks with him.

I will be overjoyed to eat my words if they're found alive, but at this point I just don't see it happening. With luck, they may recover human remains, but even this is in doubt. I have no problem diving in an experimental sub, but it must carry an ABS certification for me to feel satisfied in its safety. These oppressive regulations and exceptionally high standards have great meaning when you are down that deep.

Here's a fascinating read for those who are interested in what may've been going on behind the scenes at OceanGate prior to this tragic accident.

https://www.yahoo.com/lifestyle/whistleblower-raised-safety-concerns-oceangate-190058533.html

[AvHdB]

I have heard and read many of the above comments. I suspect your assessment is wrong, but the realist in me says otherwise.

[Lord of the Dance]

I have heard and read many of the above comments. I suspect your assessment is wrong, but the realist in me says otherwise.

Do you think they're still alive? Apparently the vessel boasts 96 hrs. of life support, which is 24 hrs. more than the standard of three days... so theoretically they could still be alive. I feel so bad for the mother / wife of the Pakistani father and son. Hopefully she's out of the picture or something because that would absolutely kill my mother.

A simple but smart method of operating any one-atmosphere submersible is to dive slightly positively buoyant and use thruster power to motor down. Yes, this consumes more battery power, but it's a basic failsafe - if you lose power, you automatically rise to the surface. I employ this strategy with my little sub and have never had a problem. Mechanical drop weights are another failsafe that is hard to F-up. With one major exception to either of these strategies though - entanglement. If a sub becomes entangled with something on the bottom, all bets are off and theoretically this could have happened to the Titan. The thing is though, I don't think they had enough time to even reach the bottom before comms were lost. All evidence points to implosion. But God, please let them be found alive!

[andrewfi]

Given that they lost contact about 90mins into a 240 minute descent, they ain't coming back. They flatter than a slice of Wonderloaf.

[Manny]

Apparently, it's 12500 feet (2.4 miles) down. The water pressure must be huge at that depth.

[andrewfi]

If they're underwater they're dead, even if still, for the moment, breathing.

If they're on the surface they have a chance. But given this incident occurred on descent, something catastrophic will have happened.

At least it will have been a rapid demise.

[AvHdB]

Likewise I doubt anyone is still alive. Sort of wonder if they will find the submersible and need Dutch expertise to raise and recover it.

Where is Cuffy when he can not post images of Nuclear bombs exploding?

[Lon]

  if an implosion at 9000'+, there are not going to be any remains

"With luck, they may recover human remains"

"They flatter than a slice of Wonderloaf."

I read/watched an article about the actual physics of what happens in a submarine, even the shallow depths of military subs.  the sudden increase of pressure at 9000'+ (some 270+ atmospheres) raises the air/oxygen temp. enough to incinerate all organic material in the submersible.  it would happen so fast the the occupants would not even know what happened until they were at the pearly gates.

[Markje]

I heard today in Dutch news that the glass used for the windscreen they will use to observe the titanic was certified only to 1 mile depth, this was already a problem because the titanic was much deeper in the ocean.

[Manny]

More on this here: https://www.gbnews.com/news/titanic-submarine-update-victims-alive-sos-atlantic-ocean

[Lord of the Dance]

Regrettably at this time it must be stated that the the five occupants of OceanGate's Titan submersible are dead. Even with a full supply of oxygen and scrubbing agent the small vessel's life support systems would have been exhausted by now (over 96 hrs). I still maintain that the crew died on Sunday when their vessel imploded, having reached probably 80% or so the depth of Titanic. 

There were clearly major design flaws with this machine. One that is obvious to anyone who understands ASTM / ABS standards for pressure vessels fit for human occupancy is that personnel hatches must have the ability to unlatch and open from both inside and outside. The fact that those people were bolted in from the outside is a big no-no. Obviously you couldn't open a hatch at depth, but you need the ability to free yourself on the surface in case of fire, etc.

As more information comes to light about the design and construction of this ill-fated submersible, it's a wonder as to why it has taken this long for catastrophe to strike.

[Bodine]

A closure. RIP

[Lord of the Dance]

(C&Ping this post from the personal submersibles forum as my sentiments are the same here. RIP OceanGate Voyagers)

So the mysterious disappearance of the Titan submersible is no longer a mystery - she collapsed. But to me a vital question remains unanswered: why, after so many different entities raised concerns over the use of the carbon composite hull, did leadership forge ahead anyway? The fact that the CEO was aboard would seem to indicate he was confident in his hull, but why? Did he feel he knew better than all these other folks who raised concerns? If it were one or two people who disagreed, that would be one matter, but it would seem there's a list a mile long of those who raised serious safety concerns (including 'amateur builders' like Karl Stanley). Did any of the passengers on this voyage understand the highly controversial decision to build with carbon fiber? The highly experienced Frenchman who had logged so much time at Titanic was unconcerned? As Carsten points out, wouldn't the guy have been suspicious that there was no second submersible or at least ROV for mission redundancy?

Alan, I totally understand the practicality of using off-the-shelf parts and components for non-critical applications, but as Alec suggests, it's a matter of optics. After this episode, when the USCG asks to take a look at one of our homebuilt submersibles and sees a game controller, what are they going to think of? Among the many tasteless jokes being tossed around online in the wake of this tragedy, one of the more G-rated ones went something like this: The only time 'homemade' and 'submarine' should be used in the same sentence is when you're making a sandwich in the kitchen! This is a PR disaster for the homebuilt submersible community. ~ Doug S. 

[Lord of the Dance]

(A telling response to my comments above)

Doug,

Trying to apply logic here won't work. When I was co-chair of the manned underwater vehicle committee at the Marine Technology Society, our chairman Will Kohnen wrote what was essentially a letter of censure to OceanGate and Rush. I critiqued that letter and was one of the 38 signatories. Stockton Rush ignored that letter. Our opinion simply didn't suit him. He lumped us all into the bunch-of-50-year-old-white-guys category, and dismissed us out of hand. Of course, you can understand his skepticism. We only had collectively about a thousand years of experience and a jillion dives between us. So, what did we know?

Vance

[Lord of the Dance]

(A descriptive post from an experienced submersible pilot)

I see that social media (and some of the mainstream media) are still talking about recovery of the bodies. I think we need to be clear - there are no bodies. When a submersible hull collapses it moves inwards at around 1500mph. About 2200 feet per second. The time for complete collapse is thus somewhere between 1 and 2 milliseconds (thousandth of a second). Apparently the human brain responds instinctually to a stimulus at about 25 milliseconds, Human rational response - from sensing to acting - is believed to be at best 150 milliseconds. When the hull collapses the air ahead of the pressure wave ignites, and the initial implosion is accompanied by an explosion of the air. Human bodies are incinerated and turned to ash practically instantaneously. In the case of Titan - it all happened so quickly the 5 aboard would (luckily) have no inkling there was a problem. No suffering at all. And that at least is a comforting thought.

[AvHdB]