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Debris found came from missing Titan sub, says friend of passengers

bbc.com

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Re: Debris found came from missing Titan sub, says friend of passengers

#101

Post by LeifCarrotson »

tivert wrote: post #89

Why has this sub been so hard to find? I keep seeing reports that they've search an area "the size of" Massachusetts or Connecticut. Shouldn't OceanGate have recorded the exact coordinates where it was released and then been able to localize its possible location to a small area around that by modeling ocean currents or something? My understanding the Titan was designed to sink to the bottom and could only move very…

> by modeling ocean currents or something

This sounds a lot like https://xkcd.com/793/ - "and then add some secondary terms to account for ."

They lost contact 105 minutes into a 120 minute, 2.5 mile descent. The release point for that descent was well known, and currents estimated closely enough to allow the sub to descend close enough to the shipwreck that the submersible's thrusters could move it very slowly to viewing locations.

They don't know what happened to cause it to lose contact more than a quarter mile above the ocean floor. They didn't know whether it went neutrally buoyant at that point, whether it ascended quickly, or slowly, or stayed near the bottom of the ocean and continued looking at the Titanic and only later drifted off course - they've done that before. Those ocean currents, unknowns, and distances are large; merely pulling the release point from a GPS track does not suddenly make the search point tiny.

Re: Debris found came from missing Titan sub, says friend of passengers

#102

Post by pillefitz »

margalabargala wrote: post #40
fuzzbazz wrote: post #12

Earlier quoted context omitted.

Would the implosion have been loud enough? I mean the thing was a tiny 7x3m cylinder located 700Km from the nearest coast...

I have no idea specifically how loud it would have been. However with some probably-reasonable guesses, it looks like it actually would have been quite loud. Here's a naval study where they measured underwater sound propagation: https://www.navymarinespeciesmonitoring.us/files/7514/2780/4... They found that a 10lb block of C4 exploding produced ~210db of underwater sound. If we use that sound level as an approximatio…

"not completely unreasonable" does a lot of heavy lifting here. I have zero intuition how the sound of an under water explosion of c4 compares to an implosion.

Re: Debris found came from missing Titan sub, says friend of passengers

#103

Post by psychphysic »

TT-392 wrote: post #98
RIMR wrote: post #78

Earlier quoted context omitted.

>Hopefully future subs will have more safety features. From an engineering standpoint, Titan didn't have any safety features at all. What any sane engineer would recommend as a last-ditch backup system Oceangate relied on as a single-point-of-failure. No phone. No beacon. Budget bluetooth controller and touchscreens. Electronics you'd expect to find in an RV. All from a CEO who flaunted his corner-cutting and apathy…

You can't just have a phone that works at those depths

I've been thinking about this problem.

Would an iPod glued to the inside that played yellow Submarine by the Beatles.

At what range would that be detectable? How long could it last?

Edit: even better this banger on loop https://youtu.be/uzR5jM9UeJA

Re: Debris found came from missing Titan sub, says friend of passengers

#104

Post by dadzilla »

margalabargala wrote: post #40
fuzzbazz wrote: post #12

Earlier quoted context omitted.

Would the implosion have been loud enough? I mean the thing was a tiny 7x3m cylinder located 700Km from the nearest coast...

I have no idea specifically how loud it would have been. However with some probably-reasonable guesses, it looks like it actually would have been quite loud. Here's a naval study where they measured underwater sound propagation: https://www.navymarinespeciesmonitoring.us/files/7514/2780/4... They found that a 10lb block of C4 exploding produced ~210db of underwater sound. If we use that sound level as an approximatio…

Volume is more like a tenth of that, I think? Maybe interior dimensions 2 meters diameter and 5 meters length gives around 16 cubic meters if my math is sane (Religion major, so go easy on me if not).

Re: Debris found came from missing Titan sub, says friend of passengers

#105

Post by civilitty »

agumonkey wrote: post #77
akira2501 wrote: post #68

Earlier quoted context omitted.

I thought that loss of communication was an expected part of the trip due to the depth.

I wonder if typical deep sea exploration use relay all along the descent, to ensure comms and raise rescue capabilities.

The three main methods are: acoustic using SONAR to receive data, tether or umbilical cord, and buoy based where the DSV releases a buoy that ascends to the top.

Relays don't really work because you'd need a LOT of them and they'd all have to keep themselves positioned within like 30 meters of each other which is very hard with ocean currents. That's with very low bandwidth VLF radio.

Re: Debris found came from missing Titan sub, says friend of passengers

#106

Post by MallocVoidstar »

tivert wrote: post #89

Why has this sub been so hard to find? I keep seeing reports that they've search an area "the size of" Massachusetts or Connecticut. Shouldn't OceanGate have recorded the exact coordinates where it was released and then been able to localize its possible location to a small area around that by modeling ocean currents or something? My understanding the Titan was designed to sink to the bottom and could only move very…

They looked on the surface because they didn't have anything that could go down to the Titanic. A ship with an ROV that could go to the Titanic arrived and they found the debris on the sea floor.

Re: Debris found came from missing Titan sub, says friend of passengers

#107

Post by anigbrowl »

eigenspace wrote: post #94
tivert wrote: post #89

Why has this sub been so hard to find? I keep seeing reports that they've search an area "the size of" Massachusetts or Connecticut. Shouldn't OceanGate have recorded the exact coordinates where it was released and then been able to localize its possible location to a small area around that by modeling ocean currents or something? My understanding the Titan was designed to sink to the bottom and could only move very…

> Shouldn't OceanGate have recorded the exact coordinates where it was released and then been able to localize its possible location to a small area around that by modeling ocean currents or something? Modelling and knowing surface currents is one thing, but this submersible was thousands of meters deep. Deep ocean currents can be very fast, change often, and we have way less data on them.

'Telemetry? who needs it'

- Oceangate, probably

Re: Debris found came from missing Titan sub, says friend of passengers

#108

Post by kyleblarson »

typeofhuman wrote: post #83
bambax wrote: post #53

If it did implode in multiple pieces it means the experts were right; many said that carbon fiber was a poor choice because while it's light, it breaks like glass, contrary to steel which tends to "open" slowly.

It's a shame they openly did not hire SMEs.

This quote shines light on his hiring philosophy: “When I started the business, one of the things you’ll find, there are other sub-operators out there, but they typically have, uh, gentlemen who are ex-military submariners, and they — you’ll see a whole bunch of 50-year-old white guys,” Rush told Teledyne Marine in a resurfaced interview.

“I wanted our team to be younger, to be inspirational and I’m not going to inspire a 16-year-old to go pursue marine technology, but a 25-year-old, uh, you know, who’s a sub pilot or a platform operator or one of our techs can be inspirational,” said Rush.

Re: Debris found came from missing Titan sub, says friend of passengers

#109

Post by somenameforme »

dylan604 wrote: post #51
psychphysic wrote: post #36

RIP to these guys, yes it was a risky trip. But it was into international waters and they were AFAIC explorers. Stuff like this can not be done without risk. Hopefully future subs will have more safety features.

I might feel this way to the first people to land on Mars or something. This was not a "mission" to advance human knowledge. To me, it's one step away from "hold my beer"

Each and every mission had scientific objective and research being carried out, precisely to help combine entertainment/adventure with technological and scientific progress. The same will be true on Mars. The earliest guys going over, as colonists, are going to be quite well to do - which I'm sure the news will frame in a completely fair and reasonable way.

Re: Debris found came from missing Titan sub, says friend of passengers

#110

Post by MallocVoidstar »

WhereIsTheTruth wrote: post #87

This story is weird to me Considering the current geopolitical weather and the presence of Russian submarines, you'd think the US army would be able to locate the missing object in no time, even with a triangulated location, they failed Worrying times

Military submarines don't go this deep.
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