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I bet the US Navy has classified ocean floor maps that are far beyond those available to the public. Knowing the ocean floor better than your opponents is like

I bet the US Navy has classified ocean floor maps that are far beyond those available to the public. Knowing the ocean floor better than your opponents is likely to be a big advantage when playing the various cat and mouse games with attack and ballistic missile subs that the US and the Soviet Union played for decades.

wheelerof4te 3y ago
I doubt it. Most of the ocean floor is very deep, so deep that even modern submarines can't reach it. If I were a non-human, intelligent species, that would be a perfect place to hide.
- Aerroon 3y ago
  To add: the test depth for the Virginia-class submarines is 240 meters. The previous Seawolf-class had a test depth of 490 meters. The average depth of the Pacific ocean is around 4000 meters. The average depth of the Atlantic is about 3600 meters.
nabla9 3y ago
Still not good enough. US Navy subs have underwater collisions from time to time. In 2015 USS San Francisco collided underwater sea mount at full speed. It was supposed to be deep blue sea. In 2021 USS Connecticut collided with underwater mountain in South China Sea. US Navy needs to map ocean floor only to 500 meters to keep it safe for submarines but they can't even do that.
- runeofdoom 3y ago
  Were the collisions due to mapping error or human error? Afaik, the USN hasn't said.
  - dragonwriter 3y ago
    Human error in both cases, though both involved incomplete charts (the ridge the Connecticut hit was uncharted but there were all kinds of command/procedure errors that contributed to hitting it [and a number of significant command/procedure problems involving the ship in the months prior to the collision], the seamount the San Francisco hit in 2005 was marked as a possible hazard on charts the crew had but not the one used for navigation and the notation wasn't transferred to the charts used for navigation.)
- virtue3 3y ago
  To be honest; that is actually a pretty dramatically good operational excellence. I wouldn't be surprised if the uss connecticut was a resolution issue with the mapping system. And also I think it might be hard for the USN to get accurate maps of the south china sea currently. "San Francisco's captain Commander Kevin Mooney was reassigned to a shore unit in Guam during the investigation of the collision. The Navy concluded that "several critical navigational and voyage planning procedures" were not being implemented aboard San Francisco, despite Mooney's otherwise remarkably good record. Consequently, the Navy relieved Mooney of his command and issued him a letter of reprimand." "The seamount that San Francisco struck did not appear on the chart in use at the time of the accident, but other charts available for use indicated an area of "discolored water", an indication of the probable presence of a seamount. The Navy determined that information regarding the seamount should have been transferred to the charts in use—particularly given the relatively uncharted nature of the ocean area that was being transited—and that the failure to do so represented a breach of proper procedures. Nonetheless, a subsequent study by UMass Amherst indicated that the Navy's charts did not contain the latest data relevant to the crash site because the geographical area was not a priority for the Defense Mapping Agency" source: https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711) https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711) So it looks like the USN charts are not exactly cheap to generate. And there is a large human element of knowing where the charts are mostly accurate and where there is information missing. Also keep in mind both of these are attack submarines and not Ohio class which generally are routinely patrolling the sea very deep and remaining as operationally quiet as possible to act as nuclear deterrents. I think their track record is more interesting because they have to patrol and be extremely quiet (zero sonar). The SSN/fast attack subs usually are escorting other groups / actively following targets so they end up in situations they can't entirely control.
  - randombits0 3y ago
    The reason current mapping data is difficult to find/distribute is because it is secret.
- nradov 3y ago
  The US Navy reports from the 2005 (not 2015) USS San Francisco and 2021 USS Connecticut groundings can be found here. In both cases primary blame was placed on the crew, although charts were a contributing factor. https://www.cpf.navy.mil/FOIA-Reading-Room/ https://www.cpf.navy.mil/FOIA-Reading-Room/
  - dylan604 3y ago
    If you have accurately marked charts but fail to use them, charts were a contributing factor. However, it is the human error that was the blame.
- dragonwriter 3y ago
  > In 2015 USS San Francisco collided underwater sea mount at full speed. It was supposed to be deep blue sea. First, it was 2005, not 2015. Second, the seamount they struck was marked on charts the crew had as a potential hazard, they failed to review those charts and transfer the notation to the chart used for navigation. > In 2021 USS Connecticut collided with underwater mountain in South China Sea. And not long before that, with a pier at Naval Base Point Loma.
  - TheCleric 3y ago
    Had the pier been mapped? ;)
- pauldenton 3y ago
  https://en.wikipedia.org/wiki/Ehime_Maru_and_USS_Greeneville_collision https://en.wikipedia.org/wiki/Ehime_Maru_and_USS_Greeneville... There's other kinds of Sub collisions as well
dylan604 3y ago
Any ship using sonar to map the floor would not be able to do so in secret. The only hope it would have would be to take advantage of just how vast the ocean is. However, sound carries a long long long way, and it would be very difficult to have a ship doing this in secret. Any opfor ship could just tail behind the ship and passively listen to the same signal and generate their maps in secret.
- citrin_ru 3y ago
  The ship will not go in secret but the resulting map can be kept in secret if military decides it makes sense.
  - dylan604 3y ago
    Again, you miss the point that while they might want to make it secret, anyone following the mapping ships can secretly have a copy of those same maps.
    - antifa 3y ago
      Sounds harder than just making your own maps tbh.
- 123pie123 3y ago
  not sure if ths is a daft question or not, but could they just reduce the power of the sonar?
  - CapitalistCartr 3y ago
    If you can pick it up, so can they.
  - dylan604 3y ago
    It's hard to appreciate just how sensitive the towed array sonars actually are. The line from Hunt For Red October about a boat off the coast of San Francisco hearing a boat "way the hell out by Pearl" is something that always comes to mind. One could do some mapping by listening to the reverberations from underwater rock slides and other naturally occurring sources of sounds--if you just so happen to find yourself in the right spot at the right time.
troupo 3y ago
Submarines still travel in what are basically shallow waters, there aren't that many of them, and mapping ocean floor isn't their primary mission. So, however detailed those maps are, I'd wager that they are still largely "here be dragons".

wheelerof4te 3y ago

I doubt it. Most of the ocean floor is very deep, so deep that even modern submarines can't reach it. If I were a non-human, intelligent species, that would be a perfect place to hide.

Aerroon 3y ago
To add: the test depth for the Virginia-class submarines is 240 meters. The previous Seawolf-class had a test depth of 490 meters. The average depth of the Pacific ocean is around 4000 meters. The average depth of the Atlantic is about 3600 meters.

nabla9 3y ago

Still not good enough. US Navy subs have underwater collisions from time to time. In 2015 USS San Francisco collided underwater sea mount at full speed. It was supposed to be deep blue sea. In 2021 USS Connecticut collided with underwater mountain in South China Sea. US Navy needs to map ocean floor only to 500 meters to keep it safe for submarines but they can't even do that.

runeofdoom 3y ago
Were the collisions due to mapping error or human error? Afaik, the USN hasn't said.
- dragonwriter 3y ago
  Human error in both cases, though both involved incomplete charts (the ridge the Connecticut hit was uncharted but there were all kinds of command/procedure errors that contributed to hitting it [and a number of significant command/procedure problems involving the ship in the months prior to the collision], the seamount the San Francisco hit in 2005 was marked as a possible hazard on charts the crew had but not the one used for navigation and the notation wasn't transferred to the charts used for navigation.)
virtue3 3y ago
To be honest; that is actually a pretty dramatically good operational excellence. I wouldn't be surprised if the uss connecticut was a resolution issue with the mapping system. And also I think it might be hard for the USN to get accurate maps of the south china sea currently. "San Francisco's captain Commander Kevin Mooney was reassigned to a shore unit in Guam during the investigation of the collision. The Navy concluded that "several critical navigational and voyage planning procedures" were not being implemented aboard San Francisco, despite Mooney's otherwise remarkably good record. Consequently, the Navy relieved Mooney of his command and issued him a letter of reprimand." "The seamount that San Francisco struck did not appear on the chart in use at the time of the accident, but other charts available for use indicated an area of "discolored water", an indication of the probable presence of a seamount. The Navy determined that information regarding the seamount should have been transferred to the charts in use—particularly given the relatively uncharted nature of the ocean area that was being transited—and that the failure to do so represented a breach of proper procedures. Nonetheless, a subsequent study by UMass Amherst indicated that the Navy's charts did not contain the latest data relevant to the crash site because the geographical area was not a priority for the Defense Mapping Agency" source: https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711) https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711) So it looks like the USN charts are not exactly cheap to generate. And there is a large human element of knowing where the charts are mostly accurate and where there is information missing. Also keep in mind both of these are attack submarines and not Ohio class which generally are routinely patrolling the sea very deep and remaining as operationally quiet as possible to act as nuclear deterrents. I think their track record is more interesting because they have to patrol and be extremely quiet (zero sonar). The SSN/fast attack subs usually are escorting other groups / actively following targets so they end up in situations they can't entirely control.
- randombits0 3y ago
  The reason current mapping data is difficult to find/distribute is because it is secret.
nradov 3y ago
The US Navy reports from the 2005 (not 2015) USS San Francisco and 2021 USS Connecticut groundings can be found here. In both cases primary blame was placed on the crew, although charts were a contributing factor. https://www.cpf.navy.mil/FOIA-Reading-Room/ https://www.cpf.navy.mil/FOIA-Reading-Room/
- dylan604 3y ago
  If you have accurately marked charts but fail to use them, charts were a contributing factor. However, it is the human error that was the blame.
dragonwriter 3y ago
> In 2015 USS San Francisco collided underwater sea mount at full speed. It was supposed to be deep blue sea. First, it was 2005, not 2015. Second, the seamount they struck was marked on charts the crew had as a potential hazard, they failed to review those charts and transfer the notation to the chart used for navigation. > In 2021 USS Connecticut collided with underwater mountain in South China Sea. And not long before that, with a pier at Naval Base Point Loma.
- TheCleric 3y ago
  Had the pier been mapped? ;)
pauldenton 3y ago
https://en.wikipedia.org/wiki/Ehime_Maru_and_USS_Greeneville_collision https://en.wikipedia.org/wiki/Ehime_Maru_and_USS_Greeneville... There's other kinds of Sub collisions as well

dylan604 3y ago

Any ship using sonar to map the floor would not be able to do so in secret. The only hope it would have would be to take advantage of just how vast the ocean is. However, sound carries a long long long way, and it would be very difficult to have a ship doing this in secret. Any opfor ship could just tail behind the ship and passively listen to the same signal and generate their maps in secret.

citrin_ru 3y ago
The ship will not go in secret but the resulting map can be kept in secret if military decides it makes sense.
- dylan604 3y ago
  Again, you miss the point that while they might want to make it secret, anyone following the mapping ships can secretly have a copy of those same maps.
  - antifa 3y ago
    Sounds harder than just making your own maps tbh.
123pie123 3y ago
not sure if ths is a daft question or not, but could they just reduce the power of the sonar?
- CapitalistCartr 3y ago
  If you can pick it up, so can they.
- dylan604 3y ago
  It's hard to appreciate just how sensitive the towed array sonars actually are. The line from Hunt For Red October about a boat off the coast of San Francisco hearing a boat "way the hell out by Pearl" is something that always comes to mind. One could do some mapping by listening to the reverberations from underwater rock slides and other naturally occurring sources of sounds--if you just so happen to find yourself in the right spot at the right time.

troupo 3y ago

Submarines still travel in what are basically shallow waters, there aren't that many of them, and mapping ocean floor isn't their primary mission. So, however detailed those maps are, I'd wager that they are still largely "here be dragons".