Project-76 Indigenous Diesel-electric Submarine (SSK) Program

[Parthu]

Has the design for Project 76 already been finalised?

As per last update, it's in detailed design stage.

I'm not sure if that was such a wise decision before absorbing the Tech from German Type 214 with Indian specific upgrades, maybe we can built the Project 76 submarines in phases where we can incrementally upgrade the submarine while absorbing the tech or implement it in Project 77. Anyway, it's good that things are progressing at this level.

And what happens if the P-75I deal falls through and the TKMS boat never comes? We lose both P-75I and P-76 and become fully dependent on French? That's not ideal now is it.

I feel the P-76 will be pursued in parallel with P-75I for the most part, but with fully indigenous tech. And that would be as per design, this dual-mode approach was originally envisioned back in the 90s' sub plan. I may not agree with it fully but that's still the plan it seems.

So now x shape rudder, stealth outer shaping(like p75i),

This was to be expected actually.

nor any iep(hence no pumpjet) ,

Nothing to do with each other in this case. It's possible we implement IEP. Likely in fact.

Pumpjet is pretty much an unnecessary extravagance for a diesel boat anyway. The Shortfin Barracuda's pumpjet was pretty much a way to fleece more money out of the Aussies. A non-nuclear boat is never going to sustain the kind of transit speeds where a pumpjet's cavitation-suppression capabilities can justify the cost.

Nuclear boat is a different matter. There's a reason why even the gold-plated SSKs like Type-212CD, Orka or Blekinge-class don't bother with pumpjets.

and it still has aip insted of fully li-ion

Fully li-ion (better of solid state batteries are possible) is far far superior while giving much more flexibility and much usable in any war

No, full li-ion in place of AIP (new Japanese approach) is a way to leverage technology to reduce complexity & cost. But AIP+Li-ion (which is what we're likely to adopt) is far superior performance-wise as it gives you the best of both worlds.

 

[Tatvamasi]

You're treating shipbuilding like a factory output problem, while I'm treating it like a naval capability problem. Faster delivery is a valid advantage, but it doesn't automatically outweigh better endurance, more mature AIP technology, greater growth potential, and stronger technology absorption. A submarine expected to serve for four decades should be judged primarily on what it can do over those four decades, not just on which one leaves the dockyard first. That's why the Navy selected P-75I in the first place.

P75I is for better "tech" as you said. But P75 follow on is to continue the current line in the MDL. Since the entire program delayed we are probably going for evolved version of the already inducted product which gives us balance of speed and everything else you listed above. This is just entering production with indonesia. But it looks likes frenchies tried to mlik us one last time now here we are.

 

[PhotonVish]

No, full li-ion in place of AIP (new Japanese approach) is a way to leverage technology to reduce complexity & cost. But AIP+Li-ion (which is what we're likely to adopt) is far superior performance-wise as it gives you the best of both worlds.

Nope. A full li-ion can give similar undewater endurance at similar speed comapred to a good aip

But problem with aip:
-> once its consumed, u need to go to harbour to refill it
-> u can not use it recklessly and go on sprint

Advantage of li-ion:
-> li-ion can be fully refilled and can be used for high speed underwater use and then when threat level is low, just recharge it without going to harbous(which is becoming more and more dangerous as seen in russia ukrain war)

-> u can use your whole battery within 2-3 days of demanding conflict, move to secure/distant place. Refill batteries and then again go to combat (Far superior tactics and response time, suprising enemy)

Fully li-ion dont need u to go to harbour while aip need u to go when used hence very constrained usage and tactics

 

[Parthu]

Nope. A full li-ion can give similar undewater endurance at similar speed comapred to a good aip

But problem with aip:
-> once its consumed, u need to go to harbour to refill it
-> u can not use it recklessly and go on sprint

Advantage of li-ion:
-> li-ion can be fully refilled and can be used for high speed underwater use and then when threat level is low, just recharge it without going to harbous(which is becoming more and more dangerous as seen in russia ukrain war)

-> u can use your whole battery within 2-3 days of demanding conflict, move to secure/distant place. Refill batteries and then again go to combat (Far superior tactics and response time, suprising enemy)

Fully li-ion dont need u to go to harbour while aip need u to go when used hence very constrained usage and tactics

Bro, having AIP doesn't remove LIBs.

AIP is useful to keep as a source for hotel load/slow speed maneuvering while retaining LIB in reserve for high-speed burst. As I said, best of both worlds.

The KSS-III already uses this AIP+LIB setup.

 

[batman]

P75I is for better "tech" as you said. But P75 follow on is to continue the current line in the MDL. Since the entire program delayed we are probably going for evolved version of the already inducted product which gives us balance of speed and everything else you listed above. This is just entering production with indonesia. But it looks likes frenchies tried to mlik us one last time now here we are.

That's why I specifically said,

ideally we could make both and absorb the tech if possible for future indigenous platforms.

 

[Anupu]

https://twitter.com/x/status/2063139052753449402

View attachment 52042

I don't think it has VLS, or at least not Brahmos VLS. Look at the beam-to-length ratio; it's 10.

That means if we want to fire an 8.4m Brahmos, with such a flush VLS, we would need a beam of 9 meters, the very least, which would make it 90 meters long. That is longer than taiga. Easily 5000 tons class category.

 

[Parthu]

I don't think it has VLS, or at least not Brahmos VLS. Look at the beam-to-length ratio; it's 10.

That means if we want to fire an 8.4m Brahmos, with such a flush VLS, we would need a beam of 9 meters, the very least, which would make it 90 meters long. That is longer than taiga. Easily 5000 tons class category.


View attachment 52058

If VLS is indeed present, by the timelines we're looking at, it would probably be the 6m BrahMos-M/NG in question anyway.



LRLACM would also be the same 6m.

We'll see.

 

[PhotonVish]

Bro, having AIP doesn't remove LIBs.

AIP is useful to keep as a source for hotel load/slow speed maneuvering while retaining LIB in reserve for high-speed burst. As I said, best of both worlds.

The KSS-III already uses this AIP+LIB setup.

But aip do take money, space and weight and volume

Why not just use those resources and add a bigger li-ion battery ?

Thats what Japanese did.

Anyways what u said, "Best of both world" is already in any aip subs except of li-ion its lead acid and its low energy dense

As lead acid was low energy dense hence having seperate aip was good idea but now with li-ion(and then ssb) , we can get 2-3 weeks of underwater as low speed with only li-ion

But aip do take money, space and weight and volume

Why not just use those resources and add a bigger li-ion battery ?

Thats what Japanese did.

Anyways what u said, "Best of both world" is already in any aip subs except of li-ion its lead acid and its low energy dense

As lead acid was low energy dense hence having seperate aip was good idea but now with li-ion(and then ssb) , we can get 2-3 weeks of underwater as low speed with only li-ion

Infact i would say, semi sold state batteries are produced at industrial scale

We should get them,
they are much safer than li-ion or aip or any thing else

They also offer much better energy density and much better cycle life

My opinion:
go with semi sold for first 6 boat and fully solid with next 6(obv x shape rudder and all other things are necessary too)

We dont want/need 2000s submarine(scorpion) in 2035

 

[Tatvamasi]

That's why I specifically said,


ideally we could make both and absorb the tech if possible for future indigenous platforms.

Again complete hogwash statement.

You cant make cake and eat it too. This "Ideally" is not possible. Which is the entire point. Nine SSKs are lined up for decommissioning.

 

[batman]

Again complete hogwash statement.

You cant make cake and eat it too. This "Ideally" is not possible. Which is the entire point. Nine SSKs are lined up for decommissioning.

"Nine SSKs are retiring" is an argument for replacing submarines quickly, not an argument against technology absorption or future capability. Those are different problems, not mutually exclusive ones.

 

[Tatvamasi]

"Nine SSKs are retiring" is an argument for replacing submarines quickly, not an argument against technology absorption or future capability. Those are different problems, not mutually exclusive ones.

Its obviously mutually exclusive. Thats why i used the phrase.

You need to prioritize. Here the priority is capability gap. Its the same for every procurement. Why didnt we sink billions without offsets for S400 ? Immediate needs. Why build Talwar when we have Nilgiri? All choices are about how to spend taxpayer money wisely for optimal utilization.

Writing we should get fanciest and coolest looking shit at cheap cost with full tech absorption and fast delivery is lazy as f thinking.

 

[batman]

Its obviously mutually exclusive. Thats why i used the phrase.

You need to prioritize. Here the priority is capability gap. Its the same for every procurement. Why didnt we sink billions without offsets for S400 ? Immediate needs. Why build Talwar when we have Nilgiri? All choices are about how to spend taxpayer money wisely for optimal utilization.

Writing we should get fanciest and coolest looking shit at cheap cost with full tech absorption and fast delivery is lazy as f thinking.

You're arguing against a much stronger claim than the one I made. I didn't say India should buy the fanciest submarine available, get full tech transfer, pay less, and receive everything tomorrow. I said that ideally we should maximize technology absorption while building fleet strength.

The funny thing is that every example you gave S-400, Talwar, Nilgiri shows India balancing immediate requirements with long-term capability building, not choosing one and abandoning the other. That's the exact point I was making.

 

[Tatvamasi]

You're arguing against a much stronger claim than the one I made. I didn't say India should buy the fanciest submarine available, get full tech transfer, pay less, and receive everything tomorrow. I said that ideally we should maximize technology absorption while building fleet strength.

The funny thing is that every example you gave S-400, Talwar, Nilgiri shows India balancing immediate requirements with long-term capability building, not choosing one and abandoning the other. That's the exact point I was making.

You said exactly that, you want everything on a sub and now rolling back.

we should be looking to procure more modern and advanced tech and built the fleet from there, ideally we could make both and absorb the tech if possible for future indigenous platforms.

Faster delivery is a valid advantage, but it doesn't automatically outweigh better endurance, more mature AIP technology, greater growth potential, and stronger technology absorption.

You should "ideally" stop making vague hogwash statements which is not conducive to constructive discussions.

It appears that you are from a corporate environment and got used to this kind of language. This is not a email thread with your HR.

 

[Lolwa]

This is nothing to do with Hangor. Its the same old 24 sub requirement.

6 P75 + 6 P75I + 3 follow on of either according to above report + 9 P76 = 24

Services do not work in a vacuum, nor are they reactionary as you expect. All is part of their long-term plan because you need to gain the confidence of other stakeholders when proposing an acquisition.

Sure, that's why we are buying the R-37 in 2026. And I never said about the requirement of P-76 being a response to Hangor but the timing of the sanctioning of the order.

 

[Ashwin]

Sure, that's why we are buying the R-37 in 2026. And I never said about the requirement of P-76 being a response to Hangor but the timing of the sanctioning of the order.

R-37 is a missile not a platform. You cant plan consumables. When the warfare changes you will need amendments.

Also, there is no confirmation of R-37, and there is no order placed for P-76. It will take 3-4 years.

 

[Ankit Kumar]

Why not order 3 more each of Type 216 variant and Scorpene. Instead of my monthly tax of 15,000 going to cursed cockroachs under various ladli and berozgar yojnas, I would rather have it be used for subs. I can bear waterlogging in gurgaon for a few more years if it means we get more subs.

PS: May death be upon the 80 billion leaches.

 

[Lolwa]

Why not order 3 more each of Type 216 variant and Scorpene. Instead of my monthly tax of 15,000 going to cursed cockroachs under various ladli and berozgar yojnas, I would rather have it be used for subs. I can bear waterlogging in gurgaon for a few more years if it means we get more subs.

PS: May death be upon the 80 billion leaches.

The biggest irony is that our scorpenes still don't have AIP. While the pakistanis have 2 submarine classes with AIP's.
And we have members here who are crying about the French milking us instead of pointing out the ridiculous procurement process.
Also our scorpenes still don't have any actual offensive capabilities.

 

[Ankit Kumar]

The biggest irony is that our scorpenes still don't have AIP. While the pakistanis have 2 submarine classes with AIP's.
And we have members here who are crying about the French milking us instead of pointing out the ridiculous procurement process.
Also our scorpenes still don't have any actual offensive capabilities.

I am waiting for the EHWT test from Scorpene. We had an agreement with NG for it.

And hopefully by 2027 we should be getting the Black sharks too.

Hopefully we get sub launched land attack cruise missiles integrated to this too. Will complete the system.

Hope is a beautiful thing and a terrible thing simultaneously.

 

[batman]

You said exactly that, you want everything on a sub and now rolling back.

Nope, try reading it again until you understand it.

You should "ideally" stop making vague hogwash statements which is not conducive to constructive discussions.

It appears that you are from a corporate environment and got used to this kind of language. This is not a email thread with your HR.

The word "ideally" literally acknowledges that constraints exist. It's strange that you've interpreted a statement about balancing priorities as a demand for unlimited budgets and zero trade-offs. That's your reading, not what was written.

 

[batman]

Why not order 3 more each of Type 216 variant and Scorpene. Instead of my monthly tax of 15,000 going to cursed cockroachs under various ladli and berozgar yojnas, I would rather have it be used for subs. I can bear waterlogging in gurgaon for a few more years if it means we get more subs.

PS: May death be upon the 80 billion leaches.

Just a small correction: I think you meant type 214 rather than type 216.
As far as I'm aware, type 216 never progressed beyond the conceptual stage.

While Germany and Italy operate the Type 212A which is more stealthy because of it's non magnetic hull, the type 214 has much longer range, depth and endurance suited for our needs along with being longer. Our Type 214 might also incorporate technologies from the Type 212CG being developed for the Norwegian and German Navies.

That said, I do agree it's worth discussing a mix of additional Scorpènes and German submarines would provide the best balance between fleet numbers, capability, and technology absorption.