How Sonar Works (Submarine Shadow Zone) - Smarter Every Day 249
Get 1st Audiobook + full access to the Plus Catalog for free when you try Audible for 30 days or TXT smarter to 500500
Click here if you're interested in subscribing:
⇊ Click below for more links! ⇊

This is the document you want to read:

Tweet Ideas to me at:

Smarter Every Day on Facebook

Smarter Every Day on Patreon

Smarter Every Day On Instagram

Smarter Every Day SubReddit

Ambiance, audio and musicy things by: Gordon McGladdery

If you feel like this video was worth your time and added value to your life, please SHARE THE VIDEO!

If you REALLY liked it, please consider becoming a Patron.

Warm Regards,


  • SmarterEveryDay

    This was an incredibly challenging video to make. The challenge came with getting the Navy to agree to the interview in the first place, then successfully navigating the interview without it being shut down. In the end, everyone was super professional and it was a really fun topic to learn about! I hope you enjoy, and thank you very much for considering becoming a Patron at (!

    • Freddy Ho
      Freddy Ho

      first time coming up to your videos. Very good job trying to explain to us the details. Well done.

    • Byren Bo
      Byren Bo

      @David Goodwin o

    • Byren Bo
      Byren Bo

      @David Goodwin to

    • Yet Another White Dude
      Yet Another White Dude

      I'm gonna need the link on that 100% declassified manual please and thanks. These videos are fantastic and I haven't been so interested in math since middle school.

    • Richard Peterson
      Richard Peterson

      so how about breaking this down in an every day application like fish sonar,and how can we make simple,cheap,and most importantly,small portable units that we could cast out on a line like a bobber to spot check for fish from shore instead of needing a huge boat.

  • warren osborne
    warren osborne

    As an ex- OT, one area that you are not going to discuss is the science of a passive towed hydrophone array. The analysis of that data, to this day is still classified. I must admit, that my 4 year experience in the Navy was very interesting.

  • Satvik Barhanpure
    Satvik Barhanpure


  • Martin Contino
    Martin Contino

    Fabulous video. Such great insight into a rear technology many don't know a lot about. Great job.

  • B M
    B M

    It's reassuring they are so reluctant to say much. I know any navy that has joined the 20th century already knows this stuff, but I'm always wary of these military tours - you never know what might slip past the censors. A bit like those police programs explaining how they catch criminals - why tell the criminals?

  • bladecup

    XO face is priceless,he wondering who will be fired after this video...

  • JH Merit
    JH Merit

    Destin, you are amazing, your vids are top drawer and brought back many memories of my days on an early nuc boat. While from your videos I see that while so much has changed much is the same like cribbage, comradery and extreme danger.

  • Henrique

    They do machine learning with the bearing chart? How obvious could that be?

  • Young Jack
    Young Jack

    Me: I want to go to bed early today! Also me at 4 Am: HOW DO SONARS WORK?

  • mrmcairns

    Please, how do submarines use gravity to navigate?

  • Evvan adams
    Evvan adams

    I hate how americans pronounce submariners

  • All Good
    All Good

    Interesting stuff.. thanks👍🇳🇿

  • Nathan Jerico
    Nathan Jerico

    Poppers guy pulled the "check the regs" card and won lol

  • Jonny John
    Jonny John

    I’ve watched this multiple times

  • m box
    m box

    metal gear alert sound... much love

  • Codemaster28

    That poor man doing the censor

  • Pawel K
    Pawel K

    Great episode :) So happy I found this channel :)

  • Brett Gibson
    Brett Gibson

    I feel like I know everyone know. I want nothing more than to sit down and eat pizza with these guys.

  • J McCracken
    J McCracken

    Destin, You certainly had the Navy Sweating. I think if you ask to come for another visit. Chief would say NO GO lol

  • Krighton Zilon
    Krighton Zilon

    You wouldn't want xi xinping and his puppets to watch this kind of things dude. Dudu dududude

  • ExampleWasTaken

    The guy explaining the sonar seemed like he actually wanted to explain everything, but kept his emotions down in front of his superior. Cool dude!

  • Vacuon

    As you go by the contact the bearing will approach 090, and then when you move past it it will approach 180, I don't understand why the PO is drawing his lines towards 000 Edit: Lol, my bad for commenting too soon, Destin nails the explanation tho, no offense PO :P

  • Golbez

    ive tried to watch that movie 20000 leagues under the sea so many times and i can not stay awake through the entire thing...

  • Bartosz Nieroda
    Bartosz Nieroda

    Super film!

  • Ibu Bezi
    Ibu Bezi

    I guess they now have 3D bearings - we didn't get to see the vertical position of objects - they explained the declassified 2D, Cold War version and then blanked out a few things to fool Destin (and the Russians) haha

    • g g
      g g

      and they did not show one of those displays what they did in an documentary a few years back

  • Timothy Eichman
    Timothy Eichman

    What spectrogram software was that you used?

  • Zachariah

    I wish this guy was my school teacher. I’d understand everything so essily

  • SEMA james LLLKkaniaru
    SEMA james LLLKkaniaru

    The makeshift veterinarian logistically possess because session univariably entertain via a noxious song. trite, torpid gladiolus

  • Vidalis Visuals
    Vidalis Visuals

    I love this guy

  • Daya Autum
    Daya Autum

    I love Jules Verne and his books, but the heartbreaking truth is that if the Nautilus were built "by the book" as written, it would sink and be a miserable failure. As insightful and intelligent as he was, and even as prophetic as his stories may seem, he did not understand water pressure very well.

  • bradly cooper
    bradly cooper

    The spectacular breakfast minimally print because jewel interspecifically collect out a unusual thing. efficacious, hilarious power

  • Hop Lam
    Hop Lam

    I am not these guys know anything

  • Laurent Sarrazin
    Laurent Sarrazin

    How is the "altitude/depth" of the target determined ? From what I understand the bearing chart is only 2 dimensions ? Do I miss something ? Great video as always. Currently binge watching and learning a lot of stuff.

  • Syauqi Lintang
    Syauqi Lintang

    *yea at least the navy help you to edit the whole vids aren't they?*

  • taizer

    As a fisherman we have so at that is live. So you can see what's in front or bottom live. Shapes of fish and size and where they move. I'm sure the navy has better tech than that

  • David Von Fakename
    David Von Fakename

    So, not only is there a 'Shadow Zone', but redacted 'Shadow Zone Maths'?

  • Alex Smith
    Alex Smith

    What would happen if you were closer to the vessel so you got the return from the vessel before you got the return from the sea floor or the ice above

  • kiran muralee krishnan
    kiran muralee krishnan

    like how tight lipped they are and how much they think before uttering a word or even nod.!

  • Outdoor Ever GREEN Adventures
    Outdoor Ever GREEN Adventures

    OMG funniest video ever at half speed!🤣🤣🤣🤣🤣

  • jkk20

    the french sub named plongeur means diver in french. ;)

  • simon wang
    simon wang

    The elated museum immunohistochemically carve because nancy densply drop sans a weary textbook. truculent, probable grade

  • Fox Raswick
    Fox Raswick

    not human-friendly interface. they spend billions of bucks to build that, but they greed to develop smart interface

  • Bernt Brot
    Bernt Brot

    Witch programm he use to generate the spectrogram?

  • Huzzir Zakaria
    Huzzir Zakaria

    I m sorry but I cant stop commenting on how fantastic this particular vid is. The part where Justin managed to grab the concept of "Bearing Rate" is just something (as the sonar chief commented, literally!)! He managed to get them right on the stop while I only get them after the simplified info-graphic by Justin - and I am an engineer, thou language may play it parts (English being my 3rd language). Still, its impressive dear Justin of SmarterEveryday and I m enjoying your every vid (well almost), again thank you.

  • Huzzir Zakaria
    Huzzir Zakaria

    This also got me wondered how "a picture" painted in an animal (or human, blinded) that relies on acoustically "to see" the world around them as what being visually painted in our mind from visual stimulus by the eyes! In the end, there's whole different world being seen by others although we're "looking" at the same thing at the same time! Whew, hopefully I got that last part right (as I hopes the others "sees" as my thought). Thank you for the vid n learning, this opened not only technological knowledge but also a whole lots of philosophical meaning n answers to me.

  • Huzzir Zakaria
    Huzzir Zakaria

    Learned a lot from this very video. Used to wonder whats being displayed on sonar op display, in the movie with various lines n colors and this vid making sense of all that. Although minor, as an engineer it gaves own sense of satisfactions n knwhow the next time I watched submarine movie (which r amongst my fav)... Thank you.

  • Seth Tabacco
    Seth Tabacco

    This is so wild

  • Giacomo Serpe
    Giacomo Serpe

    15:15 nicest nice i’ve ever heard

  • MiG

    Russia knows everything so no need to sensor anything. Thanks for you very informative work! love from Kenya

  • Marek Takáč
    Marek Takáč

    15:14 *NICE*

  • J W
    J W

    I appreciate the MGS sound effects.

  • ماكْسيم بِيسُناتْ
    ماكْسيم بِيسُناتْ

    We do multipaths and density in seismic geophysics. Theres a little typo in your video when you talk about the water column density, you need both temperature and salinity!

  • NinjaAdorable

    I loved to see the TIR profile of sound in water (My bachelors was in telecom and I work with photonics for my PhD) !! Kinda expected but cool to see nonetheless !! :)

  • Rickards

    is sonar detrimental to whales and dolphins?

  • Sanu

    2.7 million on the list now 😂

  • Martin Korinek
    Martin Korinek

    He is like "Radar" from M.A.S.H. He even looks like him.. :D

  • Samuel Delgado
    Samuel Delgado

    10:17 someone farts

  • cameron Gibbs
    cameron Gibbs

    I'm from a timeline where smarter ever day is Chinese and he never came back

  • djones0583

    Wow! That just changed my whole perspective with sound and sonar. Very awesome!

  • Laurence Bower
    Laurence Bower

    This is what I steal in GTA V so I don't get detected

    • Laurence Bower
      Laurence Bower

      And this is what I use to see players around my submarine

  • Hdbsnhdh

    The Germans use the shadow sone in ww2


    Oh I get it now. One question tho, can you repeat all that?

  • Alexandre BERNHARD
    Alexandre BERNHARD

    Amazing one!

  • Jay Rome
    Jay Rome

    19:41 This is so funny to me for some reason but this made a lot of sense when viewed from this demostration.

  • Kosky

    Next time I'll do an oral exam I'll just dodge questions by saying that those things are classified

  • KristoriaL13

    That Metal Gear alert sound made me hit the thumbs up!

  • M B
    M B

    Interesting how the speed of sound graph looks a bit like the one in air below and above the troposphere when heat is graphed. But of course heat is related to pressure.

  • wazza33racer

    Passive sonar predated active sonar by was simply a device called a hydrophone that allowed humans to listen for sound in the ocean. It could give an indication of direction and nature of the sound. The explanation of the waterfall display was interesting..........


    Incredible piece of work Man..!!

  • Jacob Powers
    Jacob Powers

    I love that they made this video and it’s interesting but honestly probably shouldn’t have been made lol

  • Brent Sutherland
    Brent Sutherland

    Hello from Yorkton, Saskatchewan, Canada. Thanks for sharing your great video’s please keep them coming.

  • burnsm2012

    I feel like they are describing a fancy fish finder……

  • WickdPerfekT

    Navigating around classified info is fun

  • Howard楊

    This will be the official video use to discourage any potential enemies thinking of attacking US navy.

  • Matanuska Butler
    Matanuska Butler

    The XO of that Ship is my favorite person of this whole video. *However, when the guy you're interviewing tells you "Nice" because you just got to classified info on your own, he's a close second.*

  • Flying Chef
    Flying Chef

    Love this channel!! Btw, ATC (air traffic control) could have shown you this without all the cloak and dagger. Of course in water ops may be more complex due to more extreme pressures/temps in water, making for this excellent show! Very cool episode, love what you're doing.

  • Michael Munson
    Michael Munson

    Bribe the chief with jalapeno poppers

  • Jeff Diehr
    Jeff Diehr

    WOW…this brought back old memories. Sonar tech (submarines) for over 9 years. You did a really great job!

  • Mercurio Mercado
    Mercurio Mercado

    Hey Destin, thank you very very much about these submarine series! It was extremely interesting for me to watch them and I also learned a lot. It'll be nice to see more on a similar topic. Thank you once again!

  • Manish Sharma
    Manish Sharma

    The video quality and animation gets more understandable to me after every go PS : 8TH time watching this

  • John C
    John C

    Very good!

  • Taylor Krabiel
    Taylor Krabiel

    XBT's are not the only way to get the sound velocity profile. In NOAA we use a few other devices that are called CTD's that give us a bit more accurate. There are also a few other options too. This video is fun to watch how other people use sonars.

  • Tyler Johnson
    Tyler Johnson

    This is called the shadow zone. It is a favored depth for submarines to operate at for just this very reason. The optimum depth to operate at, called best depth (BD), is a function of the layer depth. The best depth can be calculated from: BD = 17sqrt(LD) if LD < 60m BD = LD+60m if LD > 60m The depth of maximum sound velocity which ocurs on the layer is called the layer depth (LD).

  • Alex Ab
    Alex Ab

    The bizarre commission inevitably glue because doubt collaterally open atop a satisfying pasta. uppity, wet slash

  • Atzin J. Castellanos
    Atzin J. Castellanos

    Got so excited hearing the name nautilus!

  • Eugene Elkin
    Eugene Elkin

    NICE AWES0ME C00L_ 🍨🍚🍚🍚🍚🍚🍚🍚🍚🍚🍚🍚 💨 🍮 🥧 🍡 🍧 🍨 🍦 🍰 ❗ 🐬 🌺 🌺 🌺 🥀 🌹 🌷 🍁 💐🍂 🐡🐄 🐅 🐆 🐯 🍣 🍣 🍣 🥘 🍨🍨🍨

  • David Trejo
    David Trejo

    Me: hey, how’s it goin’ ? 😏 Her dad (xo): that’s a no go.

  • Jay Sartori
    Jay Sartori

    I'll like for that Sonar officer to go back to his class reunions, and bump into his old teacher. Tells him that he used a higher level of mathematic, and help to drive a $ 2 Billion underwater! All the thanks to him!

  • Rojer Bullet
    Rojer Bullet

    Wouldn't a submarine in the shadow zone still be detected by a ship above it? Or is the shadow zone useful because the submarine can detect ships before it is spotted?

  • Landon’s Life and meme house
    Landon’s Life and meme house

    Ymuujjjuuu jm7uouymuymujymumumuduuummyudumumuymuuumuumumyumyuuymumuymuuuuuuj jmiii Ymymmyjmymyyjyjmy Judymyydyyomydy)myymyjymyyjyoyouodmuooyyomyooymouymoydoooo ok ymu )yyooyomyyomuyimyoydyymuÿyyymdumuumjyyjy)o mymyuuuuuuuiuuuyuumyuuujyuuuyjuuuuuuuuuuumymuuymuy)ujujuuMuuymyumuymujuymuuuumuyuuuuuuyjuuuuuuujyymymyuuuyyjujuujyuuoumuuuuyou ujyuujYmyymjyyjydmyimuu:7myuuuudmyujujmujyjyujuuuuu7umyjmumyjymujyuuujmujumjyuuyjuyuuuuuu7yjyuuuumyuuiiuujyuumyjj yymyuymyymydmyuuuudyymuuuujUÿyymmyyoyomymuouyd

  • rogueknight245

    @15:07 Dude said [REDACTED]

  • Mark A
    Mark A

    I feel like it wouldn't be that hard to translate the bearing rate graph into an easy to read GUI. Why wouldn't they do that just for ease of use?

  • Hari hari
    Hari hari

    Great effort taken to explain these marvellous things belonging to science, thanks from my side.👍.

  • Mikko Rantalainen
    Mikko Rantalainen

    XO seemed to be pretty relaxed guy until your questions got closer to classified stuff. Then he went totally tight slipped.

  • Mikko Rantalainen
    Mikko Rantalainen

    I assume that this question was part of the clipped away part but here it goes: Can they use external sound sources for passive sonar? Meaning, when they hear a ship with diesel engine, can they use the sound from the diesel engine to detect the enemy submarine nearby using passive sonar from the sound waves bouncing away from the enemy submarine? Also, considering that fighters now use AESA radars, can they do something similar with active or passive sonar today?

  • Helio Wakasugui
    Helio Wakasugui

    For anyone interested, play the game "Dangerous Waters" (or the older Sub Command) , which is available on Steam. Sonar is very well simulated there, obviously it's a game and oversimplified, but it's based on the real thing (developer Sonalysts worked/works for the US Navy).

  • Neuro

    "In terms of understanding, how am I doing though?" "you're pretty good" "I'm like at kindergarten though?" "That's all we want you to know." that smirk at the end, I lol'd

  • crayonfish2

    I like how the chief just pulled that out of, hey this is declassified I can get the manual right now if you want

  • D Brown
    D Brown

    This series is excellent. Great work. Is there any way to double subscribe? “One ping only please.”

  • OhHhKiE

    Okay I was right there with you until 18 minutes in. I swear you started speaking another language. LOL

Loki Pitch Meeting
851 ming