
Veteran submariner on how sonar crews tirelessly hunt enemies they can't see - clouddrover
https://www.thedrive.com/the-war-zone/35603/veteran-submariner-on-how-sonar-crews-tirelessly-hunt-enemies-they-cant-even-see
======
adriancooney
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.

~~~
jonplackett
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 so big
chance of Chinese whisper type errors.

I don’t know how realistic it is to real life but it gives you an appreciation
for how smart and situationally aware the captain of the ship needs to be.

~~~
wcarey
The book by C.S. Forester that the movie is based on is even more realistic,
though the movie is pretty good.

To really dig into it, Samuel Eliot Morison's magisterial History of Naval
Operations in World War II does a good job talking through the development of
both the technology and organization of naval operations.

Not all communication was by morse code. We did use ship to ship voice radio,
but it was a tradeoff. RDF allowed the enemy to triangular the position of the
broadcasting ship, and (often) the enemy could overhear messages and infer
some tactical details.

Sensor systems changed wildly throughout the war. Sonar improved markedly, and
radar went from non-existent to able to identify altitude and distance to
individual planes. The weight of the additional sensor systems and controls
systems made some ships unstable, so we removed weapon systems from them.

Being a captain (or, heaven forbid) and admiral, was very demanding. Sleep was
hard to come by, and the fog of war was intense. We had meaningful problems
with friendly fire in night engagements even _with_ radar and radio
communications.

~~~
Goronmon
_To really dig into it, Samuel Eliot Morison 's magisterial History of Naval
Operations in World War II does a good job talking through the development of
both the technology and organization of naval operations._

Man, that looks like a hard series of books to actually get a hold of. Either
spending multiple hundreds of dollars for a used set, or struggle to find
individual copies for $15+ each (a quick google search seems to show Vol 2
unavailable anywhere I looked).

~~~
wcarey
I think there's a new paperback printing under way. Happily, it's not the end
of the world acquiring them piecemeal, as each volume tells a coherent story
and takes some time to read through!

------
tantaman
Oh man, I worked on the software for these systems for 6 years :)

specifically the ones from this image
[https://www.thedrive.com/content-b/message-
editor%2F15972209...](https://www.thedrive.com/content-b/message-
editor%2F1597220969469-lrh1k4rb4sv41.jpg?quality=60)

During the holidays we'd pump Christmas music through the sensors. We could do
this since that's what the raw data is anyway -- sound. Made for interesting
sonar displays as well as background music.

~~~
Ao7bei3s
If you can say, what does the dev version look like, physically? I assume you
don't have a dev ship? So same HW, just in an office? Or remote access to HW
in a server room? Or is there a more desktop friendly form factor? Or all
virtualized?

~~~
james_s_tayler
It would be fun to be that guy saying but dev/QA/prod should all look the
same.

------
oakmad
My father used to help design and build sonar of varying types for the
Australian Navy (RANRL) when I was a kid. I used to love hanging with them all
and even got to go on a submarine a few times. He had to be fully qualified
for sea trials. I assume a lot of his work was adapted from other countries,
but he still will not really get into details about what he did for them (70s
and 80s). One little nugget he told me a few years ago: their entire UI/UX
team were psychologists, engineers played almost zero role in that aspect.

------
secondcoming
This[0] youtube channel is quite good at explaining how subs work

[0]
[https://www.youtube.com/c/JiveTurkeyCrew](https://www.youtube.com/c/JiveTurkeyCrew)

~~~
evil-olive
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...](https://www.thedrive.com/the-war-zone/24638/retired-submariner-
turned-gamer-gives-amazing-video-explainers-on-sub-tactics-and-tech)

1: [https://www.thedrive.com/author/aaron-
amick](https://www.thedrive.com/author/aaron-amick)

------
canada_dry
> 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.

~~~
mhh__
That's if they aren't already.

Without having the data I can't try but I'd guess that Fourier analysis (or
something a bit more clever to deal with noise e.g. Welch) would get you a lot
of the way there even without invoking AI

~~~
zkms
This is not based on any classified information and sonar signal processing is
not something i know much about, but cyclostationarity (and other higher-order
statistical signal processing) does tend to be useful when processing signals
that are generated by processes where there's multiple periodicities at work:
[https://en.wikipedia.org/wiki/Cyclostationary_process#Angle-...](https://en.wikipedia.org/wiki/Cyclostationary_process#Angle-
time_cyclostationarity_of_mechanical_signals)

~~~
hchz
Signal separation techniques for characterizing cyclostationary signals are
also more robust to noise. For example, analysis of the second order FFT can
resolve the signals of incipient faults in rolling bearings because it can
resolve the signals of the bearing components rotating (at a much lower
frequency than the shaft) whereas simple FFT analysis would generally only
measure the magnitude of the structural resonance of the machine, with spikes
at the mains, rotational, and slip frequency.

------
munificent
Somewhat related. I went to the Oregon Museum of Science and Industry (OMSI)
in Portland last fall and did a tour of their submarine, the USS Blueback. Our
tour guide was a retired Cold War-era submariner and he was _fantastic_. He
gave us tons and tons of details about what life and working on an active sub
was actually like. It felt like being there, and you could tell he delighted
in being able to share his past with people.

~~~
dawnerd
I've been meaning to check it out, it's like right there too.

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forgotthepasswd
This[0] is an interesting account of an accident with a submarine and how
sonar played a role in the event.

[0]
[https://en.wikipedia.org/wiki/Ehime_Maru_and_USS_Greeneville...](https://en.wikipedia.org/wiki/Ehime_Maru_and_USS_Greeneville_collision)

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ThinkingGuy
Obviously, being a skilled sonarman would seem require a good physical sense
of hearing (frequency range, etc.), but as as the article mentions, the
ability to recognize patterns is also important.

Have there been any studies or analyses to see if there's also a correlation
between skill at, say, music (relative pitch, etc.) or language (detecting
subtle differences in accents, etc.) and sonar skill?

~~~
rotten
The best sonar operators have perfect pitch, except instead of saying "that is
an A-flat but there is a ghost harmonic because the slot in the bridge for
that string is too wide" they would say "that is a 415 Hz sound with up
doppler. sounds like a 3 bladed prop with a notch on the second blade". It was
pretty amazing to watch the really good ones in action.

~~~
rotten
They would go to a bar and comment that the ceiling fan was spinning at 23
rpm, and the compressor motor on the cooler had a bad bearing.

------
hchz
I used to be a part of this when the tracking party was manned and I was
engine room sup.

Using the computer tools For fusion was definitely interesting (90’s X11
gore), with a large palette of modeling tools, but the coolest experience was
being taught to time/range plot on paper by the mustang weps.

------
bmitc
Articles like this leave a bad taste in my mouth. They venerate the subject
and participants involved and leave out the vast amount of detrimental effects
they cause.

Whales, other marine mammals, and other wildlife are affected by these
systems, and they are never considered. The Navy is currently still trying to
increase its weapons testing off the coast of the Pacific Northwest, bringing
further harm to the already decimated and declining southern resident orcas.

We have absolutely got to start understanding how our technology affects the
world _and_ making changes.

~~~
rotten
The systems described in this article are "passive". They are simply listening
to the sounds around them. This is much more common for submarines than
"active" sonar - which ensonifies the water around you and then you listen for
echos. It is those loud pings which can threaten or frighten wildlife. However
they are also like holding up a big lit sign that says "there is a submarine
here!" \- and the whole point of submarines is stealth. They say that if you
hear a ping from a submarine, it is too late - there is already a torpedo
heading your way.

source - used to be a sonar tech

------
robotnikman
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.

~~~
MrBuddyCasino
235db! Apparently also kills wales and dolphins.

[https://physics.stackexchange.com/questions/93222/could-
subm...](https://physics.stackexchange.com/questions/93222/could-submarine-
sonar-kill-a-diver)

~~~
Anechoic
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](https://fas.org/man/dod-101/sys/ship/acoustics.htm)

~~~
GCPGCP
This is what you can expect
[https://www.youtube.com/watch?v=sCmyZYYR7_s&t=90s](https://www.youtube.com/watch?v=sCmyZYYR7_s&t=90s)

This diver was near a sub base for training.

~~~
MrBuddyCasino
Comments say this was very likely not a sub‘s sonar.

