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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

#111

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

Subs I believe do not operate at those depths or anywhere close.

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

#112

It's not clear from the headline - but the debris field is on the ocean floor and was found via the USGC's remote operated submersible vehicle.

Yes on the sea floor but according to BBC: > Debris patch was found by an ROV from the Horizon Arctic, a Canadian commercial vessel which arrived last night near the Titanic wreckage site. > It was loaded with support equipment and was also carrying an Odysseus 6k ROV that can reach depths of 6,000m. https://www.bbc.com/news/live/world-us-canada-65967464?at_bb...

Thanks - maybe we'll switch to that URL since it has more up-to-date information.

(Submitted URL was https://twitter.com/USCGNortheast/status/1671907901542211584)

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

#113
post #96

https://www.bbc.com/news/live/world-us-canada-65967464?ns_mc... : > We have just had an update from dive expert David Mearns, who says the debris includes "a landing frame and a rear cover from the submersible". > Mearns is a friend of passengers aboard the Titan. > Mearns has told the BBC that the president of the Explorers Club (which is connected to the diving and rescue community), provided this new information.

Thanks - maybe we'll switch to that URL since it has more up-to-date information.

(Submitted URL was https://twitter.com/USCGNortheast/status/1671907901542211584)

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

#114

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...

How do submarines commonly fail? Is the assumption of a violent implosion warranted? I would think another failure mode could be water rushing in without the overall structure catastrophically failing, which would actually relieve pressure on the structure as it happened and be much less energetic.

It's hard enough to make a small hole that doesn't turn into a big hole under such pressure when you're trying to. Even harder for a small hole you're not expecting.

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

#115
The most likely first failure is the window. At that instant a rapid turbulent fill event would occur. The outside pressure and the hole diameter will provide a calculable interval for the internal volume to fill. At 12,000 feet = 800 atmospheres, this would be on the order of 1/20th of a second, with intense crush/shear forces = instant death as perceived. That interval can be related to the speed of sound and wavelength to make a variable frequency 'chirp' that would be of low to higher frequency. The low frequency would be in the low hertz as an estimate. At the same time inner pressure and temperature would rise to 800 atmospheres and a temperature a little above ambient. The density of water is around 800 times that of air = 800 times the weight of water would enter compared to the weight of the air within. Local temperature would prevail, increased a little by the work of compression of that air to higher pressure(quite high in concept, but quenched by 800 x mass of water. Thus the sound will not be very loud or high in frequency. A sphere of C4 will make a compression wave at somewhere over 500,000 atmosphere propagating at about 4000 meters/second = fourier square wave containing all the odd order harmonics all the way down = heard round the world. Any transient inrush plasma would be swamped and mixed with cold water = transient and of little consequence. Banging? One would hope nobody would dare bang the window, but it is conceivable they might have banged the hull in desperation if the window did not crack to attract attention? Did the noise cease at some point? or is the noise still hearable = not them?

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

#116
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…

This is something I'd also like to know. I'd assume they were assuming a worst case scenario of something like a ballast malfunction paired with a propulsion malfunction, so you have a partially buoyant (enough to stay off the ground, not enough to surface) craft being pushed both by currents, and possibly its own propulsion, in an unknown direction in some radius outside of the Titanic. I've no idea of the depth son…

Ever use a fish finder / depth finder? A narrow beam is sent in one direction, generally down, and reflections back are calculated. I would imagine that was the start of their search. After enough time or support: military grade sonar? https://man.fas.org/dod-101/navy/docs/es310/SNR_PROP/snr_pro...

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

#117
post #74

Earlier quoted context omitted.

I agree but not at 250k a head. It should be safer, but everything is done to a price point and I'm sure those on board recognised the risk of such an expedition.

I seriously doubt the victims knew how risky this trip was, even though they signed the waivers. Why would you bring along your 19-year-old son if you thought the chance of death was 1/100 or even 1/1000. The CEO, who obviously overestimated the safety of his cost-cutting design, had raised $20M in venture capital, it's not as if he had a death wish either.

Further evidence that being a billionaire isn't well correlated with being a genius.

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

#118

Earlier quoted context omitted.

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.

Kinda weird that they didn't have an optical cable tether tbh.

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

#119
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.

Carbon fiber seems like a weird choice for this application anyway because its big advantage is in its tensile strength compared to its weight.

Here, it’s in compression, not tension. And its light weight doesn’t matter.

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

#120

Earlier quoted context omitted.

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 insp…

It's doubtful he'll still inspire anyone where he's now.
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