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Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

thedrive.com

31–40 of 85 posts

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#31

This[0] youtube channel is quite good at explaining how subs work [0] https://www.youtube.com/c/JiveTurkeyCrew

The author of this article (Aaron Amick) is Jive Turkey, the same as the host of that YouTube channel [0].

His other articles for The Drive [1] are all worth reading.

0: https://www.thedrive.com/the-war-zone/24638/retired-submarin...

1: https://www.thedrive.com/author/aaron-amick

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#32

I'm not normally one to promote Hollywood but the film Greyhound (2020) with Tom Hanks does an _excellent_ portrayal of this technology (albeit slightly more primitive) in fighting German U-Boats in WW2. Well worth a watch if this interests you.

That movie and Master and Commander are two movies that helped a digital nerd like me understand how an incredibly complex system can be managed by lots and lots of humans playing very specific roles.

A film set is the same way. Also, sounds like a lot of "machine learning" shops. Hire a squad of humans to do the work until the ML/AI graduates from schooling.

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#33

> The second step in classification requires analysis. It takes 30 to 45 seconds to get a look at a new detection and discover what kind of engine she’s running, what kind of hydraulic pumps are online, and what screw blade configuration she is using. One can imagine ML making this job somewhat obsolete in the not-too-distant future.

Is it really something for ML? Shazam isn't ML, and it's the same basic thing. Take the current sound and then compare it to a huge database of known sounds. Report the result.

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#34

I've heard the sonar ping from a submarine is so powerful that it will kill you if your a diver near the sonar dome.

235db! Apparently also kills wales and dolphins. https://physics.stackexchange.com/questions/93222/could-subm...

Keep in mind that's likely not related to the dB sound pressure level in air that we're all familiar with. dB is a logarithmic ratio to pressure to a reference. In air, that reference is 20µPa, acoustic pressure in water typically uses a different reference (1µPa). There is also an adjustment of 36 dB to account for the higher impedance of water. So 235 dB in water is roughly 173 dB SPL -- still loud, but many orders of magnitude lower.

[0] https://fas.org/man/dod-101/sys/ship/acoustics.htm

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#35

Earlier quoted context omitted.

I was just going to say exactly this. It’s amazing to see them doing this with such incredibly basic technology. - Having to draw their ship and the submarine and constantly update its movement. - sonar guy is just looking at a screen that blips every now and then. - all communication by morse code - must be horrendously slow in the heat of battle - even communication within the ship is passed between multiple people…

They wargamed live during North Atlantic convoy attacks on the floor of a building in Liverpool. Players received instructions through letterboxes around the room perimeter and each could only see a fraction of the the battle. They could not see the u-boats at all as those were same color as filters they looked through. Information was radioed in from convoy escorts and scenarios were played out. Battles could last a…

There is a nice video of Lindibeige about that, with some old photos of the setup https://www.youtube.com/watch?v=fVet82IUAqQ

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#36

> The second step in classification requires analysis. It takes 30 to 45 seconds to get a look at a new detection and discover what kind of engine she’s running, what kind of hydraulic pumps are online, and what screw blade configuration she is using. One can imagine ML making this job somewhat obsolete in the not-too-distant future.

Is it really something for ML? Shazam isn't ML, and it's the same basic thing. Take the current sound and then compare it to a huge database of known sounds. Report the result.

Agreed. ML and AI are (currently) useful in situations where there is a lot of data, of different types, usually from disparate sources, often sparse, with no known pattern or causal relationship. Shazam and sonar analysis don't really fall into any of those areas.

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#37

I'm not normally one to promote Hollywood but the film Greyhound (2020) with Tom Hanks does an _excellent_ portrayal of this technology (albeit slightly more primitive) in fighting German U-Boats in WW2. Well worth a watch if this interests you.

Having read the book and then watched the movie, it’s amazing how much technical detail you don’t even get to approach in the film. This is just the nature of the medium, but the book is very focused on the captain’s inner thoughts and technical descriptions, awareness of limitations, and homages to the mental math involved. Highly recommend the book if you at all appreciated the movie.

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#38

> The second step in classification requires analysis. It takes 30 to 45 seconds to get a look at a new detection and discover what kind of engine she’s running, what kind of hydraulic pumps are online, and what screw blade configuration she is using. One can imagine ML making this job somewhat obsolete in the not-too-distant future.

Can confirm that USN and sonar systems have been using "ML" techniques since the 90s. Y'all were late to the game!

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#39
post #23

> The second step in classification requires analysis. It takes 30 to 45 seconds to get a look at a new detection and discover what kind of engine she’s running, what kind of hydraulic pumps are online, and what screw blade configuration she is using. One can imagine ML making this job somewhat obsolete in the not-too-distant future.

If you ever watched the hunt for red october, they already had computers doing this (doubt it was ML'd tho).

It is ML depending on what we're calling ML. Is gradient descent/MLE ML? If yes, then the Dallas (the US sub) in Red October was using ML.

Re: Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

#40
post #23

> The second step in classification requires analysis. It takes 30 to 45 seconds to get a look at a new detection and discover what kind of engine she’s running, what kind of hydraulic pumps are online, and what screw blade configuration she is using. One can imagine ML making this job somewhat obsolete in the not-too-distant future.

If you ever watched the hunt for red october, they already had computers doing this (doubt it was ML'd tho).

Clancy did embellish a few things and speculated rather a bit to make an entertaining scenario.

All told, a good solid read, and accurate in a bunch of not-quite critical details, but don't lean too hard on the edges of the story.

Same with Red Storm Rising. Very well told, close to a solid "what if", but lots of little touches to make it entertaining as well.

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