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In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

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Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#31

Post by hindsightbias »

changoplatanero wrote: post #20
jaywalk wrote: post #4

Earlier quoted context omitted.

Why do you think they would be detectable from space? That doesn't make any sense.

There is a technique for finding nuclear submarines from space by using satellites to look for the hot water exhaust from the nuclear reactors.

Closed cycle steam generation plants aren't going to exhaust much. They can't filter seawater fast enough for use and you couldn't run seawater through those systems w/o messing them up.

Wastewater is probably cooled before release.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#32

Post by bambax »

hinkley wrote: post #13
baobabKoodaa wrote: post #6

So the submarines can't use active sonar, because their number one priority is to avoid detection... but then these subs are all parked in the same "parking spots" in the ocean. If the favored parking spots for submarines are so rare and small that collisions happen more than once, surely that undermines their stated number one priority of remaining hidden? If someone wanted to locate enemy submarines, surely they co…

Sounds like the FAA altitude problem all over again. As altimeters got more accurate, the odds that you were flying at exactly 28000 feet went up. If an air traffic controller fucks up and puts two planes at 28000ft, they can now collide because they're ±10ft instead of ±200ft. That was the RCA of that mid-air collision over Brazil a while back. The more you try to control a thing the more problems you can have. A pa…

> That was the RCA of that mid-air collision over Brazil a while back.

Yeah the article made me think about that incident too, described here in detail:

https://www.vanityfair.com/culture/2009/01/air_crash200901

It's a great read.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#33

Post by nradov »

wil421 wrote: post #8
baobabKoodaa wrote: post #6

So the submarines can't use active sonar, because their number one priority is to avoid detection... but then these subs are all parked in the same "parking spots" in the ocean. If the favored parking spots for submarines are so rare and small that collisions happen more than once, surely that undermines their stated number one priority of remaining hidden? If someone wanted to locate enemy submarines, surely they co…

You don’t need drones. Planes and helicopters already drop sonar buoys for the exact reason you stated. A better solution would be for an escort when they get into crowded lanes. Surface ships can use active sonar to scan for other subs while being some what close to their sub. The only problem is other listeners can pick up on what is reflecting off your active sonar as well. Also the subs try to avoid ever being de…

It's not like any navy has spare surface warships with active sonar available to escort submarines through constricted navigational channels. There are also environmental concerns with active sonar due to impacts on marine life, especially cetaceans. During peacetime it's usually only allowed in designated exercise areas.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#34

Post by zoomablemind »

tjohns wrote: post #27
zoomablemind wrote: post #23

Surprisingly, no side was assigned the blame for the collision. Unlike air traffic or surface navy accident. One had a conning tower damage, the other had a bow damage; both were supposedly slow-moving at the moment. Is there such thing as right of way for subs?

How do you exercise right of way over another submarine that you don't know the position of? The whole point of submarines is that they're stealthy. Active sonor would give away their position. They're basically swimming blind. The only way this all works is the ocean is big enough that random collisions are statistically rare - but there's not much actually preventing them.

> ...They're basically swimming blind.

It did appear just like that. Shouldn't there be some proximity sensors to avert collisions with massive bodies? After all in the aftermath both subs were rendered mission incapable.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#35

Post by bambax »

sca4 wrote: post #28
uga4012 wrote: post #3

Are they really not detectable from space?

Lot of dismissive reactions to these questions, but there actually are non sound related signals we use to detect submarines and there is absolutely research on how to do that from space. This article is great, but just read the "Signal Processing" section if you're interested in space. https://www.aspistrategist.org.au/prospects-for-game-changer...

Interesting article. Also, we are now able to reconstruct a conversation by analyzing the movement of the glass on a window to the room where people are talking. It doesn't seem absolutely out of reach that we could some day detect huge underwater vessels from analyzing surface perturbations.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#36

Post by nradov »

uga4012 wrote: post #3

Are they really not detectable from space?

The US Navy has researched the possibility of detecting shallow submarines from space since at least the 1990s by looking for subtle wake turbulence on the surface. The results are classified so we don't know if they were ever successful. It's not completely impossible, but the signal to noise ratio would be extremely low.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#37

Post by baobabKoodaa »

nradov wrote: post #30
baobabKoodaa wrote: post #6

So the submarines can't use active sonar, because their number one priority is to avoid detection... but then these subs are all parked in the same "parking spots" in the ocean. If the favored parking spots for submarines are so rare and small that collisions happen more than once, surely that undermines their stated number one priority of remaining hidden? If someone wanted to locate enemy submarines, surely they co…

There are no parking spots. Ballistic missile submarines conducting deterrence patrols are assigned to large areas covering hundreds of square nautical miles. The sub then maneuvers inside that patrol area to remain as hidden as possible. They almost never stop as it's easier to maintain depth control with at least a few knots of steerageway. So a collision in open ocean is theoretically possible but highly unlikely.…

> There are no parking spots. Ballistic missile submarines conducting deterrence patrols are assigned to large areas covering hundreds of square nautical miles ... So a collision in open ocean is theoretically possible but highly unlikely.

It's misleading to describe collisions as "theoretically possible" when we have evidence that these collisions have occurred. The fact that collisions have occurred makes me think that these submarines are not randomly located in a large area where it would be difficult to locate them.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#38

Post by idoh »

zoomablemind wrote: post #34
tjohns wrote: post #27

Earlier quoted context omitted.

How do you exercise right of way over another submarine that you don't know the position of? The whole point of submarines is that they're stealthy. Active sonor would give away their position. They're basically swimming blind. The only way this all works is the ocean is big enough that random collisions are statistically rare - but there's not much actually preventing them.

> ...They're basically swimming blind. It did appear just like that. Shouldn't there be some proximity sensors to avert collisions with massive bodies? After all in the aftermath both subs were rendered mission incapable.

How would the proximity sensors work? The can’t go active sonar…

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#39

Post by dragonwriter »

nradov wrote: post #30
baobabKoodaa wrote: post #6

So the submarines can't use active sonar, because their number one priority is to avoid detection... but then these subs are all parked in the same "parking spots" in the ocean. If the favored parking spots for submarines are so rare and small that collisions happen more than once, surely that undermines their stated number one priority of remaining hidden? If someone wanted to locate enemy submarines, surely they co…

There are no parking spots. Ballistic missile submarines conducting deterrence patrols are assigned to large areas covering hundreds of square nautical miles. The sub then maneuvers inside that patrol area to remain as hidden as possible. They almost never stop as it's easier to maintain depth control with at least a few knots of steerageway. So a collision in open ocean is theoretically possible but highly unlikely.…

> large areas covering hundreds of square nautical miles.

That's...not very large.

> The sub then maneuvers inside that patrol area to remain as hidden as possible.

Given that the same concerns will drive “as hidden as possible” concerns in any sub, that further narrows the space. And unless the decisions made within that space are made in a truly random manner which approaches all equally good options equally (and tolerates a loose enough sense of “equally good” not to excessively narrow the space to start with), common cognitive biases, etc., will result in common decisions.

Re: In 2009, Two Nuclear Submarines Collided Under the Sea (2016)

#40

Post by etimberg »

yummypaint wrote: post #24
hinkley wrote: post #13

Earlier quoted context omitted.

Sounds like the FAA altitude problem all over again. As altimeters got more accurate, the odds that you were flying at exactly 28000 feet went up. If an air traffic controller fucks up and puts two planes at 28000ft, they can now collide because they're ±10ft instead of ±200ft. That was the RCA of that mid-air collision over Brazil a while back. The more you try to control a thing the more problems you can have. A pa…

These days there are special collision avoidance systems on big commercial planes: TCAS II provides the pilot with specific instructions on how to avoid the conflict with traffic. These instructions are known as a “Resolution Advisory” (RA) and may instruct the pilot to descend, climb, or adjust vertical speed. TCAS II systems are also able to communicate with each other to ensure that the RA provided to each aircraf…

I believe TCAS is built off of ADS-B which is terribly insecure https://youtu.be/CXv1j3GbgLk
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