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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

#61

Post by rfreiberger »

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…

The sad part to ponder is most likely the team on the ship knew the sub was gone right when the communications was lost but kept the information to themselves.

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

#62

Post by psychphysic »

ssnistfajen wrote: post #59
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 feel bad for the 19yo who had a whole (well-funded) life ahead of him. He was probably trusting the older adults to know what they were doing.

Good point he was with his dad right? That age you still feel invincible

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

#63

Post by ssnistfajen »

psychphysic wrote: post #62
ssnistfajen wrote: post #59

Earlier quoted context omitted.

I feel bad for the 19yo who had a whole (well-funded) life ahead of him. He was probably trusting the older adults to know what they were doing.

Good point he was with his dad right? That age you still feel invincible

Yeah. Being legally adult only means something when you are 19yo yourself. If I was in the same shoes I would've followed my dad on a cool adventure without question and definitely could not have spotted any of the glaring red flags that presented themselves before the dive.

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

#64

Post by eterm »

rfreiberger wrote: post #61
margalabargala wrote: post #40

Earlier quoted context omitted.

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…

The sad part to ponder is most likely the team on the ship knew the sub was gone right when the communications was lost but kept the information to themselves.

Apparently they've "lost communications" in many of their other trips, which is why also hints at why they didn't raise the alarm for many hours.

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

#65

Post by kamranjon »

can16358p wrote: post #57
mindslight wrote: post #50

Earlier quoted context omitted.

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.

Just note that the body was experimental: while the hull indeed have a thick titanium body, it was mixed with (don't know exactly how and where though) carbon fibers, which are known to catastrophically break under pressure if there's even a microscopic impurity or damage. At least that's what the experts say. Carbon fibers is great for lightweight things that need to bend, terrible for things to be relied under pres…

It was just the end caps that were titanium - the entire tube was just a 5inch thick carbon fiber wrap. In one of the videos with the CEO I saw him saying that he was a rule breaker because common consensus was that you shouldn't build a submarine out of carbon fiber and titanium.

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

#66

Post by onesphere »

danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

Would you ever give the enemy demonstration of your detection capabilities especially when they know you’re looking for something?

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

#67

Post by aqme28 »

adventured wrote: post #23
EA-3167 wrote: post #7

Earlier quoted context omitted.

"It imploded right away" explains everything. "It imploded later" requires at least two failures, first of power/comms, and THEN of the structure itself. Occam's Razor

Your occam is incorrectly structured. Power/comms is irrelevant to the equation in question, imploding, and doesn't add. It imploded later requires only one failure (the structural failure), just as the relatively short time duration option requires only one failure. Right away is also a later event. We have no way of knowing what its structural true condition was in terms of whether it was more likely to make it a v…

You're completely ignoring that the comms went out. All we know is that comms went out early, and debris was found later. What single failure would cause both of those pieces of evidence?

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

#68

Post by akira2501 »

danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

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

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

#69

Post by marginalia_nu »

EA-3167 wrote: post #7
ak_111 wrote: post #4

Earlier quoted context omitted.

Why is it more likely that it immediately imploded rather than after a few days? The latter is more probable to me as it has never been tested under water for more than a few hours at a stretch. This will also be consistent with your banging hypothesis which was only heard after a day or two when it got lost. And also with the fact that no immediate sound disturbance was registered with the controlling ship. I of cou…

"It imploded right away" explains everything. "It imploded later" requires at least two failures, first of power/comms, and THEN of the structure itself. Occam's Razor

> Occam's Razor

is only good as a heuristic for finding which hypothesis to test first.

It's basically a scientist's "where there's smoke there's fire".

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

#70

Post by dredmorbius »

mhh__ wrote: post #11
danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

It's known that they can detect implosions from very long distances however this is a tiny submarines so perhaps they are just using it as a training opportunity with no other information.

FWIW, there are small (and highly stealthy) military submarines and submersibles, for whom accurately determining destruction based on acoustic signatures could very well have strategic value. So those capabilities (and this opportunity) could be more significant than might appear at first blush.
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