*Amazon Link* The US Navy's Fast Attack Submarines, Vol.1: Los Angeles Class amzn.to/3Ckrp9C The US Navy's Fast-Attack Submarines, Vol. 2: Seawolf Class (SSN-21) and Virginia Class (SSN-774) amzn.to/3Cl3xmv Why are Submarines Painted Black and Not Blue? ua-cam.com/video/nBG9feRzZ_A/v-deo.html
It’s pretty pointless because they immediately log the signature of the propeller’s sound. They have done this on both sides so the only reason to hide it is actually propulsion efficiency. No matter how silent it is the signatures will be logged and identified on first contact. It’s definitely not the stealth, there’s a submariner who has an entire channel around how he tracked the Cold War subs of the ussr and how they knew them by name and encountered them multiple times. Submarines are so expensive that they are rarely launched and the enemy is aware of when and where they will be launched. They aren’t plentiful enough to be lost in possibilities of what sun could it be. So they are simply hiding the screw for knots per kw. sound signatures are simply impossible to conceal as of yet and if they were it would be with active noise cancellation which must be a heck of problem underwater because the military is aware of the tech for decades upon decades. One reason to hide the screw is to hide the number of blades because you then have a count of number of disturbances per rotation and if you understand the frequency of the engine installed you can do the math more easily to identify. Again nothing to do with technology of engineering shape more just going through the motions of not instantly giving the enemy an established number to do the math in order to predict frequency at rpm.
@snsproduc so we stop building subs because the enemy knows. That statement makes no sense whatsoever. The US has been building subs at a constant rate for the past 10 years and intel is not always accurate. I was on an ASW mission in 1986 to locate a Soviet Kilo class being sold to Iran and US intel was unsure how many blades were on the prop so we flew on it, dropped buoys, got the intel and sent it to DC. We verified what they suspected to be true.
The secret is not the information given in this video, the secret is the actual shape of the propeller. All Navy's in the world know this principle, it's teached in all the Navy school's.
It's probably just shrouded like a jet drive... Less efficient, but these nuclear subs have power to burn. It will also cut down on sound. Have not watched your entire video. Waiting... Yup, you failed to mention the obvious. The ocean is littered with loose cables and nets. Mini sub design was changed because of lethal tsngling. Even on a huge sub with only one prop, a tightly wrapped drift net eould be a total disaster. They would be forced to surface at best.
Seems like we broadcast way too much information. The average person doesn't really need to know all about this technology so why put it out for our enemies to know what we are doing and more importantly thinking. Seems like there are a lot of smart people on this channel. I know some will say they already know this stuff. Sure, good answer, but why keep telling them every little thing we do. They will rule the world one day because we can't seem to get our own political world straight why give them more information on these channels about our military secrets. You think they don't watch these videos... JMHO
It’s not so top secret if your also showing where it’s built and stored at. Especially if they leave the bay doors open and visible from satellite and space 🤦🏻♂️
What about soft propellers like flexible rubber or plastic. Or ones were the blades change pitch like planes. A skirt trailing behind the cowling might muffle the pops. Or several screws in line. Maybe a texture on the blades or even change the propeller when underway.
To help you understand, cavitation is so much louder than normal operation that it will be detected by fixed sensors and will need to be explained by the commanding officer at the end of the patrol - an awkward conversation at best ! One cavitation event can compromise the whole patrol. Loving the creativity, but ........ Soft propellors - not strong enough, but can still cavitate. Water will boil to steam and the resulting bubbles with collapse under pressure once free of the propellor's flow (=cavitation) if the partial pressure is low enough,cavitation will occur whatever you make the blades from. Variable pitch - only efficient at one speed - more liable to cavitate at others. The complexity of the hydraulics inside the shaft would probably be very unreliable and changing pitch would be noisy in its own right. Type 21 frigates used CPPs, which were unreliable in their early days. Skirts - how would this work ? It might flap like a flag and be just as noisy. Do not underestimate the loads on anything towed behind a submarine - it would probably not be there after a patrol Several screws in line - like an aero-engine compressor ? - you need to keep the flow through the "propellor" as undisturbed as possible - each new lump you introduce alters the flow and may cause more vortices and more points of low pressure (where cavitation can occur) Blade texture - the surface is carefully prepared / treated. Changing the propellor underway - what have you been smoking ? Changing a "propellor" takes a few hours in a dry dock with a crane and a gang of people who know what they're doing. This is not like a car's tyre - these things weigh tons. Even in a flat calm, I wouldn't consider doing this !
US could also build their own diesel electric AIP subs and station them in Europe or Southeast/East Asia instead of having to always send nuclear attacks subs SSNs like the Virginia class subs to those regions. Also to reduce military upkeep.
SSKs are too problematic and tactically vulnerable SSN are only limited by food stores while SSK are limited by fuel which at most is 45 days , SSN carry way more weapons than SSK but most importantly, as power is not problem, they can carry a lot more equipment than SSKs
@@verdebusterAP Nope. German Type 206 subs and Swedish Gotland class subs were able to sink US carriers in a middle of a battlegroup and other NATO ships/subs in wargaming exercises. They have their uses. When operating on its batteries, they are quieter/stealthier than nuclear subs. US is already investing on diesel electric drone subs like Boeing's ORCA. But that is just an interim solution.
They need to think outside the box on this. Maybe they could design a kind of cold jet engine of sorts. Use the reactor to heat water in an expansion chamber where it would be ejected out faster than it entered. Surely they could speed up the exhaust water faster than current propellers. They could use radiators to heat incoming sea water and shape the flow path using Bernoulli's principle so the expanding water would keep the flow going through their undersea "jet" engine. Shape it like a jet engine combustion cycle.
You may be surprised by how much thinking in and out of the box has gone into quieter ways of moving submarines around. I don; really like your jet engine idea much though - Infra red tracking from satellites would quickly detect a submarine using such a propulsion technique. Or indeed an MPA /helicopter / drone equipped with infra red vision. Don't forget that much of the thrust of a het engine comes from the conversion of cold liquid fuel into hot gaseous combustion products. Warming the water up a few degrees won't produce much thrust.
Yeah, and we all are grateful that you reveal the greatest secret. Thank god that the enemy does not speak English, they will not understand what you are writing here. And since you must be in the highest security level, you will be able to deliver information that is always current🤣🤣🤣
@@carcamp5451 why told you that I am crying ? 🥴 don't hide your tears behind your fake pride of calling India a super power ( fact : super powers don't submerge a nuclear powered submarine while keeping the hatch open 😂 I guess you what Indian navy did with the Akula class sub )
*Amazon Link*
The US Navy's Fast Attack Submarines, Vol.1: Los Angeles Class amzn.to/3Ckrp9C
The US Navy's Fast-Attack Submarines, Vol. 2: Seawolf Class (SSN-21) and Virginia Class (SSN-774) amzn.to/3Cl3xmv
Why are Submarines Painted Black and Not Blue? ua-cam.com/video/nBG9feRzZ_A/v-deo.html
Because of the rubber stealth coating 😉
It’s pretty pointless because they immediately log the signature of the propeller’s sound. They have done this on both sides so the only reason to hide it is actually propulsion efficiency. No matter how silent it is the signatures will be logged and identified on first contact. It’s definitely not the stealth, there’s a submariner who has an entire channel around how he tracked the Cold War subs of the ussr and how they knew them by name and encountered them multiple times. Submarines are so expensive that they are rarely launched and the enemy is aware of when and where they will be launched. They aren’t plentiful enough to be lost in possibilities of what sun could it be. So they are simply hiding the screw for knots per kw. sound signatures are simply impossible to conceal as of yet and if they were it would be with active noise cancellation which must be a heck of problem underwater because the military is aware of the tech for decades upon decades. One reason to hide the screw is to hide the number of blades because you then have a count of number of disturbances per rotation and if you understand the frequency of the engine installed you can do the math more easily to identify. Again nothing to do with technology of engineering shape more just going through the motions of not instantly giving the enemy an established number to do the math in order to predict frequency at rpm.
Not only prop noise is logged but any sound source being AC or DC is noted for a particular class or hull.
@snsproduc really? And why is that?
@snsproduc so we stop building subs because the enemy knows. That statement makes no sense whatsoever. The US has been building subs at a constant rate for the past 10 years and intel is not always accurate. I was on an ASW mission in 1986 to locate a Soviet Kilo class being sold to Iran and US intel was unsure how many blades were on the prop so we flew on it, dropped buoys, got the intel and sent it to DC. We verified what they suspected to be true.
The latest American submarines, since the seawolf class. do not use a propellor, they are using the device first used by the Royal Navy, a propulser
@@paulhill1665 yes the sound level is much quieter. You are talking about the pumpjet
Not on Indian subs ..no secrets 😂
SSBN's alone an exception.
Everything is top secret about the Australian nuclear submarines, even the Navy knows nothing.
As it should be
The secrets of submarine that enemy must not know!! - Only available on UA-cam!!
I agree
The actual military: "dude, not cool!"
The secret is not the information given in this video, the secret is the actual shape of the propeller. All Navy's in the world know this principle, it's teached in all the Navy school's.
"taught" not "teached".
True, true. Thank God they'll never work it out for themselves.
It's probably just shrouded like a jet drive... Less efficient, but these nuclear subs have power to burn. It will also cut down on sound. Have not watched your entire video. Waiting...
Yup, you failed to mention the obvious.
The ocean is littered with loose cables and nets. Mini sub design was changed because of lethal tsngling. Even on a huge sub with only one prop, a tightly wrapped drift net eould be a total disaster. They would be forced to surface at best.
Seems like we broadcast way too much information. The average person doesn't really need to know all about this technology so why put it out for our enemies to know what we are doing and more importantly thinking. Seems like there are a lot of smart people on this channel. I know some will say they already know this stuff. Sure, good answer, but why keep telling them every little thing we do. They will rule the world one day because we can't seem to get our own political world straight why give them more information on these channels about our military secrets. You think they don't watch these videos... JMHO
It’s not so top secret if your also showing where it’s built and stored at. Especially if they leave the bay doors open and visible from satellite and space 🤦🏻♂️
Which Japanese company sold propeller milling machine… ? Can’t remember it!
I like before watching
Same
Same to with stealth aircraft
Sure aircraft is unseen in one bandwidth but switch to another n said aircraft lights up like a Christmas tree
What about soft propellers like flexible rubber or plastic.
Or ones were the blades change pitch like planes.
A skirt trailing behind the cowling might muffle the pops.
Or several screws in line.
Maybe a texture on the blades or even change the propeller when underway.
To help you understand, cavitation is so much louder than normal operation that it will be detected by fixed sensors and will need to be explained by the commanding officer at the end of the patrol - an awkward conversation at best ! One cavitation event can compromise the whole patrol. Loving the creativity, but ........
Soft propellors - not strong enough, but can still cavitate. Water will boil to steam and the resulting bubbles with collapse under pressure once free of the propellor's flow (=cavitation) if the partial pressure is low enough,cavitation will occur whatever you make the blades from.
Variable pitch - only efficient at one speed - more liable to cavitate at others. The complexity of the hydraulics inside the shaft would probably be very unreliable and changing pitch would be noisy in its own right. Type 21 frigates used CPPs, which were unreliable in their early days.
Skirts - how would this work ? It might flap like a flag and be just as noisy. Do not underestimate the loads on anything towed behind a submarine - it would probably not be there after a patrol
Several screws in line - like an aero-engine compressor ? - you need to keep the flow through the "propellor" as undisturbed as possible - each new lump you introduce alters the flow and may cause more vortices and more points of low pressure (where cavitation can occur)
Blade texture - the surface is carefully prepared / treated.
Changing the propellor underway - what have you been smoking ? Changing a "propellor" takes a few hours in a dry dock with a crane and a gang of people who know what they're doing. This is not like a car's tyre - these things weigh tons. Even in a flat calm, I wouldn't consider doing this !
A great review of Screws and cavitation. Thank you
The secrets of submarines that enemy must not know, Thats why you tell the whole world smart.
Cool video. Maybe use better grammar for the video title though.
Hmm, very interesting . . . I learned something new today!
If it is top secret why they talk about it on here. I know about this many years ago.
" Must Not Know " and you publish it on UA-cam :)
If it's secret then why are you providing info about it.
It was a secret, but not after this video was seen.
Can’t they do the opposite and make the noise deafening to pings? Making detecting the submarine to a particular place impossible?
At Pearl Harbor they cover the screw, but left the sonar dome completely open for viewing.
'enemy most not know'? 😭😭😭
Don't you just love it when someone puts "Top Secret" stuff on UA-cam?
US could also build their own diesel electric AIP subs and station them in Europe or Southeast/East Asia instead of having to always send nuclear attacks subs SSNs like the Virginia class subs to those regions. Also to reduce military upkeep.
True. Though, there is the option of hydrogen energy also for the said above.
But AIP is much more practical....
Also U can use 2 stroke engine 😂
SSKs are too problematic and tactically vulnerable
SSN are only limited by food stores while SSK are limited by fuel which at most is 45 days ,
SSN carry way more weapons than SSK but most importantly, as power is not problem, they can carry a lot more equipment than SSKs
@@verdebusterAP Nope. German Type 206 subs and Swedish Gotland class subs were able to sink US carriers in a middle of a battlegroup and other NATO ships/subs in wargaming exercises. They have their uses. When operating on its batteries, they are quieter/stealthier than nuclear subs. US is already investing on diesel electric drone subs like Boeing's ORCA. But that is just an interim solution.
Also, the pitch of the blades figures in at what RPM is obtained before cavitation thus increasing speed.
" Secret " and the video is freely available on youtube 😂
They do now.
Bull crap
They need to think outside the box on this. Maybe they could design a kind of cold jet engine of sorts. Use the reactor to heat water in an expansion chamber where it would be ejected out faster than it entered. Surely they could speed up the exhaust water faster than current propellers. They could use radiators to heat incoming sea water and shape the flow path using Bernoulli's principle so the expanding water would keep the flow going through their undersea "jet" engine. Shape it like a jet engine combustion cycle.
You may be surprised by how much thinking in and out of the box has gone into quieter ways of moving submarines around. I don; really like your jet engine idea much though - Infra red tracking from satellites would quickly detect a submarine using such a propulsion technique. Or indeed an MPA /helicopter / drone equipped with infra red vision. Don't forget that much of the thrust of a het engine comes from the conversion of cold liquid fuel into hot gaseous combustion products. Warming the water up a few degrees won't produce much thrust.
So how do you know when its Top Secret? :D
Sub
Shhhhhh
Yes,we know already
Hydrojet
Thank you
Yeah, and we all are grateful that you reveal the greatest secret. Thank god that the enemy does not speak English, they will not understand what you are writing here. And since you must be in the highest security level, you will be able to deliver information that is always current🤣🤣🤣
It’s open source. Nothing the adversaries don’t know already.
The US makes the best sub technology
Except the Russians make the deepest diving Subs
Ay un dicho que aquí me sirve, no me acostare sin aprender una cosa más. Por ello os lo agradezco (cultura general para ....)
First comment :)
There is a saying that works for me here, I will not go to bed without learning one more thing. For that I thank you (general culture for ....)
I bet a lot of guys know the difference between every screw 😍
ThusTejas became the no.1 light fighter jet of world
Then why do the Indians fear the Chinese most 🥴🥴 even Bangladesh Air Force rejected the HAL Tejas for it's poor performance
@@shakikahnaf9783 🤣. Keep crying kid.
@@carcamp5451 why told you that I am crying ? 🥴 don't hide your tears behind your fake pride of calling India a super power
( fact : super powers don't submerge a nuclear powered submarine while keeping the hatch open 😂 I guess you what Indian navy did with the Akula class sub )
Must not be to top secret because it is on UA-cam already.