Indian Navy Developments & Discussions

Blademaster

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I have heard about these incidents in various exercises where US vessels or aircraft gets locked on frequently.

However US forces work with minimum deterrence in these excursuses and purposely allow them to get locked on.
And obtain their acoustic signatures and also their firing process. USN purposely lose so they can gather intelligence and info about these subs.
 

swapcv

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Ya'll Nibbiars

And most of the time in the Malabar Exercise we sunk every Amerikan Submarine that participates.

The Back in 2015, Indian Navys Russian built Kilo.class diesel electric attack submarines managed to sink a nuclear-powered U.S. Navy Los Angeles.class attack submarine during exercises in October. The Indian submarine INS Sindhudhvaj S56 allegedly killed USS City of Corpus Christi SSN 705 during an exercise called Malabar that is held annually between India, Japan, and the United States several years back.

The submarines were assigned to track each other down in the Bay of Bengal. The way it happens is that the Sindhudhvaj recorded the Hydrophonic Effect HE simply put, underwater noise of the nuclear powered submarine and managed to positively identify it before locking on to it. Being an exercise what did not happen was the firing. The Indian vessel then sank USS City of Corpus Christi using 533mm torpedoes.
On the fence on this, its possible a USHUS equipped Kilo upgraded to the latest Pr.8773 managed to get a firing solution on the Flt-I Los Angeles but then Nuke subs were always at a disadvantage against such subs unless you're an Astute or Seawolf/Virginia.
 

swapcv

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And obtain their acoustic signatures and also their firing process. USN purposely lose so they can gather intelligence and info about these subs.
It depends, was it a front or angled aspect shot or a shot from Baffles? Kilo's (or any contemporary SSK for that matter), especially upgraded ones do stand up to their reputation as quiet boats and their Sonar noise signature is about 30-40% quieter than their Nuclear powered SSN counterparts (especially when these boats are just creeping along at 3-5kts). Thus if the shot was taken from the Subs baffles, the likelihood of detecting or even recording any Sonar signature even with a towed array deployed is very small. The most you'll record are muffled sounds and at the last moment a launch transient.
 

Blademaster

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It depends, was it a front or angled aspect shot or a shot from Baffles? Kilo's (or any contemporary SSK for that matter), especially upgraded ones do stand up to their reputation as quiet boats and their Sonar noise signature is about 30-40% quieter than their Nuclear powered SSN counterparts (especially when these boats are just creeping along at 3-5kts). Thus if the shot was taken from the Subs baffles, the likelihood of detecting or even recording any Sonar signature even with a towed array deployed is very small. The most you'll record are muffled sounds and at the last moment a launch transient.
Doesn't matter. All they need is the acoustic signature. Once they get it, they can pick it out from any ocean. Each boat has an unique acoustic signature and USN maintains the largest library of acoustic signatures. It's so top secret that they don't even share it with their allies. They will kill their own mothers before revealing the contents of the library.

For a better understanding, check out the French film, https://en.wikipedia.org/wiki/The_Wolf's_Call
 

swapcv

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Ya'll Nibbiars it was the magnetic anomaly.
Subs don't have a Magnetic Anomaly Detector (pretty much useless as your Sub acts as a source of interference) and for an Aircraft with MAD to detect a Submarine, it will have to be incredibly close and the submarine itself at a relatively shallow depth (just near or around the scattering layer) to detect the said Sub. Also before this even occurs, an aircraft has to know the general position of the enemy Sub which can only happen if the said Sub commander was careless and managed to trigger a Sonobuoy or Dipping Sonar from a nearby Helo.
 

swapcv

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Doesn't matter. All they need is the acoustic signature. Once they get it, they can pick it out from any ocean. Each boat has an unique acoustic signature and USN maintains the largest library of acoustic signatures. It's so top secret that they don't even share it with their allies. They will kill their own mothers before revealing the contents of the library.

For a better understanding, check out the French film, https://en.wikipedia.org/wiki/The_Wolf's_Call
That film is quite unrealistic btw, so I would'nt use it as a source of reference. But yes, all Navies do maintain a repository of sonar signatures. However these are also vulnerable to being outdated and sometimes might be more of a bane than a help when you're a Sonar operator and hunting for contacts. Eg: In the 80's, Soviets began launching Subs equipped with Skewback props that used sofisticated CNC machines surreptitiously purchased from CoCom countries in violation of sanctions. This had an unlikely effect in that for many years until the collapse of the Soviet Union, newer Soviet types like the Akula, Sierra, Oscar class and also older Victor class began to slip past both SOSUS and NATO sub patrols into the Atlantic and Pacific. The West was horrified that the Soviets had managed to build such props in the first place and only realize what had happened thanks to the Norwegian Police managing to intercept a shipment bound for the USSR. For more, see Toshiba-Kongsberg Scandal.

 

Blademaster

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That film is quite unrealistic btw, so I would'nt use it as a source of reference. But yes, all Navies do maintain a repository of sonar signatures. However these are also vulnerable to being outdated and sometimes might be more of a bane than a help when you're a Sonar operator and hunting for contacts. Eg: In the 80's, Soviets began launching Subs equipped with Skewback props that used sofisticated CNC machines surreptitiously purchased from CoCom countries in violation of sanctions. This had an unlikely effect in that for many years until the collapse of the Soviet Union, newer Soviet types like the Akula, Sierra, Oscar class and also older Victor class began to slip past both SOSUS and NATO sub patrols into the Atlantic and Pacific. The West was horrified that the Soviets had managed to build such props in the first place and only realize what had happened thanks to the Norwegian Police managing to intercept a shipment bound for the USSR. For more, see Toshiba-Kongsberg Scandal.

The film may be unrealistic but I am referring to the scene where the French Navy protects its library of acoustic signatures and how you would need top secret clearance just to be able to access it and you need to get permission each time to access the library.

It doesn't matter when you use high tech to make very silent props. Once you get its acoustic signature and enter it into the database, it's marked for life until it change out the props for a new set of props. It is like being fingerprinted or getting your DNA sample and being entered into the database.

Nowadays, USN and western navies have powerful supercomputers that maintain these libraries and check off any acoustic signature they encounter against the database they have and try to identify which sub it is.
 

swapcv

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The film may be unrealistic but I am referring to the scene where the French Navy protects its library of acoustic signatures and how you would need top secret clearance just to be able to access it and you need to get permission each time to access the library.

It doesn't matter when you use high tech to make very silent props. Once you get its acoustic signature and enter it into the database, it's marked for life until it change out the props for a new set of props. It is like being fingerprinted or getting your DNA sample and being entered into the database.

Nowadays, USN and western navies have powerful supercomputers that maintain these libraries and check off any acoustic signature they encounter against the database they have and try to identify which sub it is.
Yeah but you need to get one to begin with tbh. Kilo's especially later mods (Pr.636, 636.3) and newer Russian Subs (Yasen/Yasen-M, Borei-A/Borei-B) are still not identifiable completely because, well, your USN still hasn't managed to get a Signature of them properly, something that even Supercomputers at AUTEC of the NUWC working under the direction of USN's NAVSEA can't recreate or simulate even if they fed data from grainy photos of those props. Simulations also are still just an approximation of the real thing, not the real thing itself. So while you can keep everything under lock and key, you still are missing signatures of Subs that you're more likely to encounter in the future.
 

Tridev123

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Yeah but you need to get one to begin with tbh. Kilo's especially later mods (Pr.636, 636.3) and newer Russian Subs (Yasen/Yasen-M, Borei-A/Borei-B) are still not identifiable completely because, well, your USN still hasn't managed to get a Signature of them properly, something that even Supercomputers at AUTEC of the NUWC working under the direction of USN's NAVSEA can't recreate or simulate even if they fed data from grainy photos of those props. Simulations also are still just an approximation of the real thing, not the real thing itself. So while you can keep everything under lock and key, you still are missing signatures of Subs that you're more likely to encounter in the future.
Since we are discussing nuclear submarines and stealth, an idea occurred.
Now almost everybody knows that Luneberg lenses are used to increase the radar reflectivity of aircraft(for purposes of masking and misleading enemies about the actual stealth parameters of the aircraft).

Now suppose an nuclear submarine fields an marine equivalent of the Luneberg lens which purposely increases the acoustic and magnetic signatures of the submarine by a small percentage, say about 10% to 25%. The increase should be a small percentage only(marginal) as we don't want the submarine to appear like an gigantic piece of iron on enemy sonar screens.

Also the Luneberg lens equivalent attachment should be capable of being jettisoned when required.

The submarine's acoustic and magnetic signatures even with the Luneberg lens like attachments should be near the capability of enemy submarines. We don't want to create an inferior submarine.

Now imagine that an actual war breaks out. The role of SSN's and SSBN's will be crucial to determine and change the course of the war.

Now the enemy may have collected the acoustic and magnetic signatures of the submarine beforehand by shadowing and signal intelligence operations. These signatures would be stored in the appropriate threat libraries.

But imagine that when the real war starts the command is given to the submarine to jettison and throw away the Luneberg lens equivalent equipment. So suddenly the submarine will become more stealthier and harder to detect. Its present acoustic and magnetic signatures will not match the recorded performance parameters as stored on enemy databases.

The advantage will be short lived but could possibly influence the outcome of the war.

Now whether something like this is technically feasible is to be seen.
 

Okabe Rintarou

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Since we are discussing nuclear submarines and stealth, an idea occurred.
Now almost everybody knows that Luneberg lenses are used to increase the radar reflectivity of aircraft(for purposes of masking and misleading enemies about the actual stealth parameters of the aircraft).

Now suppose an nuclear submarine fields an marine equivalent of the Luneberg lens which purposely increases the acoustic and magnetic signatures of the submarine by a small percentage, say about 10% to 25%. The increase should be a small percentage only(marginal) as we don't want the submarine to appear like an gigantic piece of iron on enemy sonar screens.

Also the Luneberg lens equivalent attachment should be capable of being jettisoned when required.

The submarine's acoustic and magnetic signatures even with the Luneberg lens like attachments should be near the capability of enemy submarines. We don't want to create an inferior submarine.

Now imagine that an actual war breaks out. The role of SSN's and SSBN's will be crucial to determine and change the course of the war.

Now the enemy may have collected the acoustic and magnetic signatures of the submarine beforehand by shadowing and signal intelligence operations. These signatures would be stored in the appropriate threat libraries.

But imagine that when the real war starts the command is given to the submarine to jettison and throw away the Luneberg lens equivalent equipment. So suddenly the submarine will become more stealthier and harder to detect. Its present acoustic and magnetic signatures will not match the recorded performance parameters as stored on enemy databases.

The advantage will be short lived but could possibly influence the outcome of the war.

Now whether something like this is technically feasible is to be seen.
Sounds like a good idea. I remember ships in The Expanse use a similar method to mask the signatures on their fusion drives. But without thinking too deeply about it, I can think of a couple of stumbling blocks:-
The biggest noise maker on a sub is the prop itself, or the pumpjet. To mask its noise with another noise from a noisemaker device would definitely be costly in terms of energy output needed, not to mention that it would create an additional thrust vector on the submarine (given that to create such a noise, you'd need to move around a lot of water).
.
Also, wouldn't it be possible to run a Fourier analysis on whatever distorted signal that does produce and still get a signature that at least closely resembles the true wartime signature of the prop/pumpjet. Because the noisemaker device is simply masking, not modifying the pumpjet/prop's noise. So will simply get two noise signatures, sort of like two fingerprints overlaid on each other. In wartime, one of those fingerprints would be present, so they'd at least be able to use pattern matching, maybe AI based, to quickly find the closest match to the noise signature in their library. Which will allow them to ID our sub regardless.
I mean this might work against torpedoes, (although I think they already use sonic decoys for that) but an enemy submarine has sophisticated signal processing, so I don't think it would work.
.
And you can't create active noise cancellation either, for it will simply cause reduced thrust as well. Not to mention how it would lead to the water in the submarine's wake to heat up.
 

Tridev123

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Sounds like a good idea. I remember ships in The Expanse use a similar method to mask the signatures on their fusion drives. But without thinking too deeply about it, I can think of a couple of stumbling blocks:-
The biggest noise maker on a sub is the prop itself, or the pumpjet. To mask its noise with another noise from a noisemaker device would definitely be costly in terms of energy output needed, not to mention that it would create an additional thrust vector on the submarine (given that to create such a noise, you'd need to move around a lot of water).
.
Also, wouldn't it be possible to run a Fourier analysis on whatever distorted signal that does produce and still get a signature that at least closely resembles the true wartime signature of the prop/pumpjet. Because the noisemaker device is simply masking, not modifying the pumpjet/prop's noise. So will simply get two noise signatures, sort of like two fingerprints overlaid on each other. In wartime, one of those fingerprints would be present, so they'd at least be able to use pattern matching, maybe AI based, to quickly find the closest match to the noise signature in their library. Which will allow them to ID our sub regardless.
I mean this might work against torpedoes, (although I think they already use sonic decoys for that) but an enemy submarine has sophisticated signal processing, so I don't think it would work.
.
And you can't create active noise cancellation either, for it will simply cause reduced thrust as well. Not to mention how it would lead to the water in the submarine's wake to heat up.
You have gone deep technically into the idea and listing out the barriers.
Appreciate the effort.
I am reminded of DARPA in the US. A lot of radical ideas are generated. Only a few of them become technically possible. A small percentage.
There will be a lot of technical challenges. No doubt. Enabling a submarine to be in two states of stealth. Wartime or enhanced stealth and peace time stealth.

But I am putting my faith in the inexorable march of technology.
We should remember barely 50 years ago ballistic missiles especially long range ones were thought to be uninterceptable. The widely accepted MAD(mutual assured destruction) axiom kept the peace between the Soviet Union and the United States.

But now intercepting ballistic missiles is no longer considered an impossible science. Of course 100% success in interception is not possible. But even if 75% to 95% success is achieved the destruction could be minimised.

Anyway India has a long distance to travel in mastering the art and science of making very quiet submarines. But we have made the initial sprint and should invest in serious R&D to further the objective.
 

ladder

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Just wanted to point out, this is probably the weakest that Indian Navy would be in the foreseeable future.

We currently have 10 destroyers 12 frigates and few corvettes.
With the many ships under construction, the size and power of IN will grow, when they join the fleet.

Now, what is the point of this post? Platform induction and decommissioning are a part and parcel of every Navy.
But, planning ensures that the operative strength never declines, that too for a growing navy of an economically growing country.

That's where we are lagging. Starting from inertia in granting AoN to DAC clearance to CCS clearance.
Then RFI to RFP and even when tendering process is done and L1 selected, a considerable time is lost in the contract signing process.

The delay and cost overrun by the shipyard and delay by NDB is also a major contributor.

Once the hull is ready, the ship waits for its compliment of sensors and armaments, which are separately procured and are plagued with their own delay.

On top of that we have capacity constraints at shipyards. Except for L&T shipyard, many private players have become bankrupt. DPSU shipyard like MDL haven't been able to expand and absorb knowhow from OEM.
GRSE has expanded by acquisition of RAjabagan dockyard and probably is the largest DPSU shipyard after modernization of RDY.
Cochin shipyard, Goa Shipyard and Hindustan Shipyard should also expand and technical expertise to build frigate and destroyer level ships should be present with all of them.

This is a good time for the Navy and GoI to reflect on what went wrong. The perspective fleet strength of Navy has been brought down from 200 to 185 ships and probably to 175 ships, as things are progressing.
 
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Dharani

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Just wanted to point out, this is probably the weakest that Indian Navy would be in the foreseeable future.

We currently have 10 destroyers 12 frigates and few corvettes.
With the many ships under construction, the size and power of IN will grow, when they join the fleet.

Now, what is the point of this post? Platform induction and decommissioning are a part and parcel of every Navy.
But, planning ensures that the operative strength never declines, that too for a growing navy of an economically growing country.

That's where we are lagging. Starting from inertia in granting AoN to DAC clearance to CCS clearance.
Then RFI to RFP and even when tendering process is done and L1 selected, a considerable time is lost in the contract signing process.

The delay and cost overrun by the shipyard and delay by NDB is also a major contributor.

Once the hull is ready, the ship waits for its compliment of sensors and armaments, which are separately procured and are plagued with their own delay.

On top of that we have capacity constraints at shipyards. Except for L&T shipyard, many private players have become bankrupt. DPSU shipyard like MDL haven't been able to expand and absorb knowhow from OEM.
GRSE has expanded by acquisition of RAjabagan dockyard and probably is the largest DPSU shipyard after modernization of RDY.
Cochin shipyard, Goa Shipyard and Hindustan Shipyard should also expand and technical expertise to build frigate and destroyer level ships should be present with all of them.

This is a good time for the Navy and GoI to reflect on what went wrong. The perspective fleet strength of Navy has been brought down from 200 to 185 ships and probably to 175 ships, as things are progressing.
Hopefully, if Adm Hari Kumar becomes the next CDS, there would be a greater focus on beefing up IN.
 

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