|
I mean, that article concludes with.quote:Meanwhile, on the message board of the Integrated Undersea Surveillance System Caesar Alumni Association (IUSSCAA), and in response to Amick’s video analysis of the newly unclassified Seawolf documents, Bruce Rule, a naval acoustic and SOSUS expert who testified at the Thresher inquiry, has stated: Honestly I literally can't imagine a casualty that causes a submarine to sink from x' to y' over the course of 24 hours, it's a completey ludicrous idea, and false sonar returns is far more plausible. Like, that's not how depth control works, if they had 24 hours they had time for EMBT to thaw, if EMBT didn't get them to the surface, their sink rate would have to be far higher than y-x'/24 hours. If they lost all electric, again, EMBT would thaw eventually and allow them to the surface, if they didn't lose all electric power, why weren't they calling for help? Hypoxia and just falling asleep at the controls makes more sense, there's abso-loving-lutely no way they slowly sank out for 24 hours. That's horseshit, and those "reports" from 575 saying "they didn't bang 5 times but they did 3" are suspicious as gently caress. I am in no way prepared to believe those onboard had 24 hours to find positive buoyancy AND somehow failed to find a way to the surface, it's bull pucky and shenanigans. Elviscat fucked around with this message at 22:55 on Apr 7, 2023 |
#
?
Apr 7, 2023 11:45
|
|
|
|
| # ? May 28, 2024 06:34 |
|
|
If you want horror stories of people who were alive well after their boat couldn't reach the surface, quote:Kursk is what you're looking for
|
|
#
?
Apr 7, 2023 11:52
|
|
|
Elviscat posted:I mean, that article concludes with. Yeah this, it wouldn't make sense for the emergency blow to not surface them like a loving cork if their sink rate was 900'/24h, since those tanks can blast a boat to the surface like a bath toy, if they can push enough water out to make the vessel buoyant. If they manage "neutral" buoyancy with an EMBT blow, they're going to sink a hell of a lot faster than 900'/24h, since their flooding is obviously not under control, all they would have bought is a couple minutes to pray. caveat I am not a bubble head at all, but the chicken switches will put almost anything except for an actively dying sub on the surface.
|
|
#
?
Apr 7, 2023 11:58
|
|
|
There's just no way you wouldn't have heard that one weird A-ganger jerking off like his life depended on it on passive, the SONAR trace would have looked like a skeleton jerking off in a trash can, is all I'm saying.
|
|
#
?
Apr 7, 2023 11:59
|
|
|
Elviscat posted:If you want horror stories of people who were alive well after their boat couldn't reach the surface, Or from our own Navy, the S-4.
|
|
#
?
Apr 7, 2023 12:02
|
|
|
MBT blows only work at test depth and above. Thats the whole point of test depth. The reports I read before was pretty much that 600 page thing but condensed into around 50ish or so pages iirc. A lot of what I remember reading was the on sight reports I don't think sosus data was in it at all. If the sosus data conflicted with the on sight reports I'll buy what sosus says for sure. I know some of the crazy stuff they were able to see.
|
|
#
?
Apr 7, 2023 12:06
|
|
|
ded posted:MBT blows only work at test depth and above. Thats the whole point of test depth. This is completely and wholly factually incorrect. "Test depth" is (crush depth)-(safety margin) All the various systems are designed to work to crush depth, and a very simple pressure=volume ratio will show that EMBT is designed to show an extremely positive buoyancy margin below test depth. Like, are you trying to make me War Thunder? EMBT is close to an order of magnitude higher then sea pressure at test depth, and the pressure difference between test and crush depth is gently caress-all. Weren't you a submariner? Apply some of what you know. Elviscat fucked around with this message at 12:18 on Apr 7, 2023 |
|
#
?
Apr 7, 2023 12:15
|
|
|
It was taught that way when I was in. Did they teach wrong or are you just trying to be that guy
|
|
#
?
Apr 7, 2023 12:27
|
|
|
This is like the night we got bored on midwatch in CDC and the TAO (all of whom that were in the rotation were P-3 pilots) explained thermocline and its cause and effect over the span of 6 hours. It was fascinating.
|
|
#
?
Apr 7, 2023 13:11
|
|
|
ded posted:It was taught that way when I was in. Did they teach wrong or are you just trying to be that guy They taught you scuttlebutt instead of science  If the sub was somehow still intact EMBT will get you positive buoyancy a lot of the way beyond crush. Just generally those margins disappear when you have something dragging you past test depth in the first place. The lovely brazes that theoretically initiated the casualty would have exponentially gotten worse as they descended. Higher pressure for a higher leak rate, higher pressure causing more brazes to fail and start to leak.
|
|
#
?
Apr 7, 2023 13:28
|
|
|
Also be very careful with posting any numbers that are not quoted directly for an approved paper or article.
|
|
#
?
Apr 7, 2023 13:30
|
|
|
ded posted:It was taught that way when I was in. Did they teach wrong or are you just trying to be that guy They taught wrong. It would be an insane way to design a safety system to start off with. Second, and I'm not trying to be pedantic here, consider the pressure to volume proportionality, in a fixed volume P1*V1=P2*V2, right? So if my other 3 variables (EMBT tank pressure, EMBT Tank volume, EMBT tank+Ballast tank volume) we see that the volume in the EMBT tanks+ballast tanks would decrease linearly, if P1*V1=P2*V2 at test depth (i.e. the EMBT system can just perfectly empty the ballast tanks fully at test depth) with air volume in the system decreasing afterward. But also consider, as depth/pressure increases so does buoyancy, also in a linear manner, so even if I can't fully empty my ballast tanks at crush depth, the amount of buoyancy I gain by pushing out what water I can, stays the same! You can replicate this at home using your bathtub and a soda bottle, notice that it requires increasingly higher pressure to push the bottle down as it goes deeper. If you open the bottle and hold it vertically, with the opening down, note that it partiality fills with water as you push it down, but completely empties by the time it's at the surface, but is significantly easier to push down to a given depth, this can be utilized to visualize the pressure/volume relationship as you increase depth. It's .44 PSI per foot of seawater, for convenient math purposes. Also it's irrelevant because the design criteria for EMBT is "completely empty the ballast tanks, at crush depth +10% margin, minimum" I'm not trying to be 'that guy' and I know there's a poo poo ton of misinformation spread in the submarine community, and I'm sorry if I come off like an rear end in a top hat here. Elviscat fucked around with this message at 13:48 on Apr 7, 2023 |
|
#
?
Apr 7, 2023 13:42
|
|
|
M_Gargantua posted:Also be very careful with posting any numbers that are not quoted directly for an approved paper or article. This makes it a pain to talk about this stuff, all the depth numbers I've quoted are from the article VVG posted, except 900' which is a math error. Probably irrelevant because my stories from the 22 are way closer to skirting classification guidelines.
|
|
#
?
Apr 7, 2023 13:47
|
|
|
Elviscat posted:They taught wrong. Now you're teaching wrong. Unless the 22 does that specifically. The criteria is a specified minimum amount of added positive buoyancy via water displaced. As you then climb and water pressure reduces, the air continues to expand, pushing more water out and shedding more ballast, until its eventually empty. You're not budging all of those many hundred tons of water all at once. But clearing up a nice new air bubble on top of all the tanks will give you a lot of sudden aid. Its one of the many axis of those operation charts for flooding and dewatering vs depth, because you only have so much safe margin as you get down to the floor. It is a lot of margin, but the ocean is a lot of water that wants to get into the people tank.
|
|
#
?
Apr 7, 2023 14:19
|
|
|
Yeah, I'm trying to simplify it, but it's absolutely designed to work to crush depth. E: the 21 class does have freaky small ballast tho. Elviscat fucked around with this message at 14:40 on Apr 7, 2023 |
|
#
?
Apr 7, 2023 14:28
|
|
|
What would even be a possible situation in which the sub could hang out losing only 40 or so feet of depth an hour? Irreparable damage to some electrical components or generation, but not all? That in combination with failure of ballast? But given enough time the lines would thaw. While strange things can happen, a leak at depth is only going to decrease buoyancy, causing loss of depth to increase in rate, causing the leak rate to increase. For them to have hung around that long I would think they would need a way to evacuate some of the water, to pump it out, which would require some amount of power, and as depth increases the harder it is to pump out. The Kursk only had initial survivors because it sank in water relatively shallow, the ship's length was longer than the depth of water in sank in. Had it been in open ocean it would have imploded as well. Submarines that start to sink either fix it pretty immediately/blow the ballast, or they start to sink faster.
|
|
#
?
Apr 7, 2023 15:32
|
|
|
so when the crush depth is exceeded and the sub goes, is it just an instantaneous thing like I would imagine due to how physics works?
|
|
#
?
Apr 7, 2023 18:48
|
|
|
It's more a statistical probability thing than a video game "You Died" prompt. You're still dead, barring incredible luck, but there are lots of different spicy possibilities for exactly how. Black bars for horrific deaths Soda can implosion remains the most likely. Once the hull starts deforming the dynamic pressure gradients start to propagate further deformation along microscopic metal grain boundaries. If the hull does not collapse a catastrophic flooding casualty can theoretically kill you from the air compression and heating before you drown.
|
|
#
?
Apr 7, 2023 19:04
|
|
|
Drowning is probably only a likely cause of death for the initial casualty that causes the vessel to lose buoyancy and begin to sink. In an implosion event the thermodynamic conditions that exist when the implosion occurs rapidly increases temperature to extreme temperatures as the hull moves rapidly inwards at up to 2500 feet per second. From time of implosion beginning to the event being concluded is roughly a few milliseconds, a shorter time than the 25ms human response time.
|
|
#
?
Apr 7, 2023 19:46
|
|
|
M_Gargantua posted:It's more a statistical probability thing than a video game "You Died" prompt. You're still dead, barring incredible luck, but there are lots of different spicy possibilities for exactly how. That is definitely up there on the scale of most horrifying things I've ever read.
|
|
#
?
Apr 7, 2023 20:16
|
|
|
Well at least it's fast enough to just blink you out w/ implosion. Thanks for explaining
|
|
#
?
Apr 7, 2023 20:18
|
|
|
Elviscat posted:They taught wrong. Sure. But was it taught to you at BESS that the *correct* answer to "what is test depth" was that? I know it wasn't to me. It was driven home in both BESS and during basic sub quals that test depth was "the max depth that an EBT blow could get you to the surface without propulsion". I know there are always huge safety margins built in to all sub gear. The navy has been paranoid as hell about the possibility of losing another submarine for good reason. quote:I'm not trying to be 'that guy' and I know there's a poo poo ton of misinformation spread in the submarine community, and I'm sorry if I come off like an rear end in a top hat here. You're just being the nuke dissing the coner. Time as old as nuclear power.
|
|
#
?
Apr 7, 2023 20:18
|
|
|
ded posted:Sure. But was it taught to you at BESS that the *correct* answer to "what is test depth" was that? I know it wasn't to me. It was driven home in both BESS and during basic sub quals that test depth was "the max depth that an EBT blow could get you to the surface without propulsion". It would appear that the Navy's definition of test depth does not take into account the ballast system directly. Perhaps it may take it into account inderectly. https://www.secnav.navy.mil/doni/Directives/09000%20General%20Ship%20Design%20and%20Support/09-100%20Hull%20Structure%20Support/9110.1D.pdf
|
|
#
?
Apr 7, 2023 20:42
|
|
|
ded posted:Sure. But was it taught to you at BESS that the *correct* answer to "what is test depth" was that? I know it wasn't to me. It was driven home in both BESS and during basic sub quals that test depth was "the max depth that an EBT blow could get you to the surface without propulsion". Old habits and all that. Great news though, neither of us are ever going to test depth, or beyond, ever again, 'cause we're not in the fuckin' Navy anymore! 
|
|
#
?
Apr 7, 2023 22:36
|
|
|
If anybody is getting puckered over the submarine stuff, the numbers they’ve given are all stuff you can work out with Excel and Derrett’s stability for masters and mates.
|
|
#
?
Apr 8, 2023 03:55
|
|
|
https://www.youtube.com/watch?v=UoyWSRBvS5I Since we're talking about sinking ships, I remembered a really good documentary on the engineers of the Titanic from about 9 months ago. Super high production values for something you'd see on Youtube.
|
|
#
?
Apr 8, 2023 05:08
|
|
|
FrozenVent posted:If anybody is getting puckered over the submarine stuff, the numbers they’ve given are all stuff you can work out with Excel and Derrett’s stability for masters and mates. I have no idea what that is but it's now on the reading list.
|
|
#
?
Apr 8, 2023 11:27
|
|
|
SquirrelyPSU posted:I have no idea what that is but it's now on the reading list. It’s a stability textbook for merchant marine deck officer, not exactly riveting materials.
|
|
#
?
Apr 8, 2023 19:46
|
|
|
FrozenVent posted:It’s a stability textbook for merchant marine deck officer, not exactly riveting materials. Don't kink shame.
|
|
#
?
Apr 8, 2023 19:53
|
|
|
FrozenVent posted:It’s a stability textbook for merchant marine deck officer, not exactly riveting materials. If you're desperate enough you can jerk it to anything.
|
|
#
?
Apr 8, 2023 19:56
|
|
|
FrozenVent posted:It’s a stability textbook for merchant marine deck officer, not exactly riveting materials. Well sure, ships are mostly welded now, right?
|
|
#
?
Apr 8, 2023 19:57
|
|
|
how to trigger anyone who has been on a sub amine
|
|
#
?
Apr 9, 2023 01:47
|
|
|
ded posted:how to trigger anyone who has been on a sub honestly the horrible deployment smell that everyone always attributes to amine almost entirely disappeared once smoking was banned.
|
|
#
?
Apr 9, 2023 02:26
|
|
|
I cannot imagine being underway and not smoking. Smoking was great because it dulled your sense of smell and everything smelled like stale smoke. A smell much better than the other stuff around!
|
|
#
?
Apr 9, 2023 02:41
|
|
|
IncredibleIgloo posted:I cannot imagine being underway and not smoking. Smoking was great because it dulled your sense of smell and everything smelled like stale smoke. A smell much better than the other stuff around! I never smoked or dipped but when we went underway (old busted surface ship, didn't go anywhere longer than a few weeks usually) I used to make space in my coffin locker for a couple-three logs of Copenhagen. I would wait until a couple days after the ship's store ran out - which they always did - and then sell them for $5 a can. Paid for my drinking money most ports.
|
|
#
?
Apr 9, 2023 02:46
|
|
|
ded posted:how to trigger anyone who has been on a sub Not as bad as triggering a mine, I suppose.
|
|
#
?
Apr 9, 2023 02:59
|
|
|
ded posted:how to trigger anyone who has been on a sub Don't worry, the next gen stuff is no longer a volatile airborne menence.
|
|
#
?
Apr 9, 2023 03:02
|
|
|
M_Gargantua posted:Don't worry, the next gen stuff is no longer a volatile airborne menence. Well thats no fun. How can the new guys get ruined clothes and that smell stuck into your mind for the rest of your life?
|
|
#
?
Apr 9, 2023 04:09
|
|
|
Depends on how well A-gang's maintaining the scrubbers too. Saw one get to the point we blew through an entire tank in like 3 weeks.
|
|
#
?
Apr 9, 2023 05:09
|
|
|
|
| # ? May 28, 2024 06:34 |
|
|
FrozenVent posted:It’s a stability textbook for merchant marine deck officer, not exactly riveting materials. Lol don't threaten me with a good time (Im a civil engineer, a former FC, and a Masters student. Dry materials outside my area of expertise are exactly my wheelhouse) Stultus Maximus posted:Don't kink shame. Wingnut Ninja posted:Well sure, ships are mostly welded now, right? Bravo.
|
|
#
?
Apr 9, 2023 11:56
|
|