Arihant-class SSBN - News & Discussions

How many intermediate class missiles are featured in SSBN worldwide ? most are near or over 2m dia class.
My point was regarding it's ejection mechanismand not about it being intermediate or Intercontinental.

No submarine ever fires its missile from deep down. The max depth for such missile launches is just abt 80m.
read my post again I said about necessary depth.... What other purpose do u think that nose fearing is for if not for providing necessary push to missile from sea.
 
Clear or not but this is one system we got to see a decent part of the initial sequence in the video, then if you merge it with the previously released k-4 video you get a very good launch video, on par with some conventional missiles and agni videos.


Both are old videos.
Posted in number 542.
 
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Considering that it's been 10+ years since K4 was first tested in 2013, don't know why there's still so much secrecy around the missile. Tests are well publicised but pics and vids are not forthcoming. I know this is our strategic deterrent but....
Uhhh...

I see it like this.

K4 development was done by 2020. Like fully done. Even navy was happy with it. Arighaat got operational in Aug 2024 and immediately went ahead with K4 integration and test firing of that missile from sub. So we see this.

Next is Aridhaman hopefully getting commissioned in 2025 with 8 K4s, enough to severely damage China in war. I believe K5 will be test fired in 2025 or early 26 with integration starting with induction of S4*. It may also happen that K-5 may not be single warhead version at all but fully mirv from get go and K-5 will be capped at 5-6000 KM . And that will remain India's status quo for many years to come, with K6 in basement.

K-5 with MIRV will be a massive deterant to china.

12-16 K5s with 3-5 warhead each is enough to push China back to 1800s.
 
I guess for now we'll just have to imagine a blunt nose RV on the ASAT interceptor (which featured the 2 stage booster from the K4) until the DRDO releases the first pics.

Next is Aridhaman hopefully getting commissioned in 2025 with 8 K4s, enough to severely damage China in war.

12-16 K5s with 3-5 warhead each is enough to push China back to 1800s

I hope we've moved on from the 250kT boosted fission warhead design though. We need atleast double the yield imo.

Dr.Santhanam's claims of the 1999 N-test being a dud would have undermined the credibility of our deterrent capability in the minds of our adversaries. It's time for another test to restore it.
 
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@marich01 @Speedster1 @randomradio
What we know about K5 and K6 as of now?

K-4 is much more Pakistan specific and does not provide full deterrence against China. K-5 is likely an upgrade over the K-4 and will target all of China from BoB. My guess is Agni III/K-4 and Agni V/K-5 provide us different options as we climb up the escalation ladder; one targets Chengdu, the other targets Beijing.

K-6 is a new S-5 specific missile with a larger diameter for global targeting. This missile will put the US and Europe in our crosshairs. And of course, better penetration capabilities against Chinese targets. I guess the S-5+ will allow our SSBNs to leave the BoB and venture deeper into the IOR, making it harder for adversaries to reach, hence the requirement of a full scale ICBM.
 
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K-4 is much more Pakistan specific and does not provide full deterrence against China.
I dunno. Sub sitting in Andaman sea can hit hongkong and Shenzen....
Thats not at all a bad deterrence. Thats like threatning to hit Mumbai in India.

Shenzen Shanghai Hongkong.

effectively, this whole is covered... And thats like more than 90% of China. The China that matters,

1733216198997.png


Put 80 nukes here... And China will be dead.
 
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I hope we've moved on from the 250kT boosted fission warhead design though. We need atleast double the yield imo.

Dr.Santhanam's claims of the 1999 N-test being a dud would have undermined the credibility of our deterrent capability in the minds of our adversaries. It's time for another test to restore it.
Well, a well place 100 KT nuke is more than enough to cripple likes of Shenzen. 3-4 RVs carring a 100 KT nuke each is end of Shenzen, Hongkong all together. And there goes a lot of Chinese economy.

I am pretty sure with 40 KT they tested, scaling to 100 KT is not really hard. Mostly how much to boost. Plutonium design boosted with tritium. I am assuming a 500 KG RV (including bomb) is enough. I think putting 100KT in a 400 KG package is not really that hard. It has been done several times in past.

Swan for instance was a 15 KT 48 KG design of 1956 vintage.
 
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a well place 100 KT nuke is more than enough to cripple likes of Shenzen
True. The decent CEP of the Agni-series should allow us to hit industrial and military sites with low-yield warheads for reduced collateral damage. However, to wipe out entire cities- or at least to build a MAD narrative vs China - I'd say yields of at least 200kT would be required. About time DRDO/AEC provided some tid bits on warhead yields for audiences in India and abroad. The Pakistani SPD via their mouthpiece Lt Gen. Kidwai is regularly engaging in nuke sabre rattling at every available opportunity.
 
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My point was regarding it's ejection mechanismand not about it being intermediate or Intercontinental.
hence my question as well, a rocket with bare 1.4m dia class can not be powerful enough to be launched from underwater and maintain the similar form factor of a much higher dia class traditional slbm in service worldwide.

It is very evident from the notam area coverage as well which are released to mark the unsafe area over the sea and air. You can see the post launch hazardous zone is around 1600-1700km area, which is on par with area coverage you need for 1.2-1.4m dia class first stage motor burnout so in case any accident happens the fallout would not affect an area more than that. But a missile like A5 and the future missiles of same or higher dia class motor stages need much greater area coverage like 3500km long area excluding the rv fallout zone (which is further 1500-2000km far away marked later) because the motors are way more powerful and if explosion happens during flight it would cover a far larger area due to being more powerful.

So think from that angle, K4 got a less dia less powerful rocker motor compared to traditional slbm, hence they made the mechanism with the nose mounted pseudo first stage which takes the missile over the sea, clears the surface to a height and nose cap ejected with the main motor firing. A very good launch method for an IRBM class slbm. During the transition, the aerodynamic fins are needed for stability. I have heard K4 being unique as well so there is chance its not just some vanilla slbm, it is something more.
 
K-4 is much more Pakistan specific and does not provide full deterrence against China. K-5 is likely an upgrade over the K-4 and will target all of China from BoB. My guess is Agni III/K-4 and Agni V/K-5 provide us different options as we climb up the escalation ladder; one targets Chengdu, the other targets Beijing.

K-6 is a new S-5 specific missile with a larger diameter for global targeting. This missile will put the US and Europe in our crosshairs. And of course, better penetration capabilities against Chinese targets. I guess the S-5+ will allow our SSBNs to leave the BoB and venture deeper into the IOR, making it harder for adversaries to reach, hence the requirement of a full scale ICBM.
Project K5 itself is made as a large dia article, bigger than A5 which is till now our most potent system. Its end rings on which the canister is held tight on is 2.8m dia, for A5 class the same end rings are - 2.4m. We have to see whether they went for increased dia on A5 daisy 2 motor itself to satisfy ssbn launch or not, but either way you need to qualify a large dia rocket motor first. It is also likely this rocket motor is crmc, not maraging steel made like the other 2 when built initially. So if you are qualifying a large dia crmc like that, it is also likely the same can be used for future land based systems too.

K6 or K8 whatever the next phase can be , so far no hint. It is of course possible as mk2 of K5, but what about the feasibility part ? if you build K5 large and powerful enough with mirv, it should negate the need for K6 ? Otherwise you face additional logistics of handling another near par system for a critical platform like an SSBN?
 
have heard K4 being unique as well so there is chance its not just some vanilla slbm, it is something more.
Like its predecessor K-15, it's safe to assume K-4 is not a pure ballistic missile. It probably flies a depressed trajectory staying within the atmosphere all the way to the target. Likely has both MIRV and MARV capability like the Agni series.
 
Like its predecessor K-15, it's safe to assume K-4 is not a pure ballistic missile. It probably flies a depressed trajectory staying within the atmosphere all the way to the target. Likely has both MIRV and MARV capability like the Agni series.
Possibly yes and as a 2nd strike option that is preferable perhaps. But its kinda hard to imagine this doing the same over such a very large distance. B-05 you can say is dual capable but proper mirv need a bit more thrust ability perhaps or limited rv carrying capacity , even less if you pack decoys in. i have not seen any pic of the rv yet so not sure what exact type it is. Perhaps an Oreshnik type system itself.
 
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Missile tests are publicized through the media for strategic signaling. The K-15/B-05 validated the sub launch, composite motor and guidance tech that eventually made its way to the K-4 follow-ons (including A4,5). And they did release missile schematics and launch pics for K-15/Shaurya.

Perhaps they haven't released pics from the latest K4 test because DRDO is still verifying the data from the launch.
k-15 is different thing, it is the first underwater project and as stated by the scientist himself, DRDL knew nothing of underwater at the time. But once the ssbn atv came into project stage, they obviously decided if the sub was being made it needed an attack capability hence B-05 took form. Now there are both B-05 and B-05LV and yet it is being remade with modern tech ie likely crmc overhaul. This particular article also had aerodynamic design where it depends on spinning to dissipate heat , not sure if they going to change it in the new form or not. But on the use case , it can be both retaliatory 2nd strike as well as preventive strike capable given Pak doctrine is first use. So a critical strike option is important where you destroy pak liquid fuel missile inventory that need some time to prepare.

K4 itself is probably the first to get that 1.4m dia booster and they were so confident on this booster that it went into asat, and no doubt AD series would also benefit from it. The more large crmc you can qualify and validate , the more data you get for future versions.

As for the launch part, its indirect confirmation of what we knew, that these missiles are all non ballistic trajectory capable, it is made to fly how the user wants it to be flown. High resistance to enemy bmd system and electronic counter measure.
 
I dunno. Sub sitting in Andaman sea can hit hongkong and Shenzen....
Thats not at all a bad deterrence. Thats like threatning to hit Mumbai in India.

Shenzen Shanghai Hongkong.

effectively, this whole is covered... And thats like more than 90% of China. The China that matters,

View attachment 38539

Put 80 nukes here... And China will be dead.

In terms of range alone, it can target Beijing.
 
I hope we've moved on from the 250kT boosted fission warhead design though. We need atleast double the yield imo.
American, GB, French warheads are more in the 100 - 300 KT.
The goal was to have more but smaller warheads on the same missile.

Previously the warheads was bigger (MT) because less accuracy.
 
Project K5 itself is made as a large dia article, bigger than A5 which is till now our most potent system. Its end rings on which the canister is held tight on is 2.8m dia, for A5 class the same end rings are - 2.4m. We have to see whether they went for increased dia on A5 daisy 2 motor itself to satisfy ssbn launch or not, but either way you need to qualify a large dia rocket motor first. It is also likely this rocket motor is crmc, not maraging steel made like the other 2 when built initially. So if you are qualifying a large dia crmc like that, it is also likely the same can be used for future land based systems too.

K6 or K8 whatever the next phase can be , so far no hint. It is of course possible as mk2 of K5, but what about the feasibility part ? if you build K5 large and powerful enough with mirv, it should negate the need for K6 ? Otherwise you face additional logistics of handling another near par system for a critical platform like an SSBN?

A K-5 larger than K-4 will mean a new design and won't fit in the Arihant class. Or the S-4 will require a new VLS.
 
A K-5 larger than K-4 will mean a new design and won't fit in the Arihant class. Or the S-4 will require a new VLS.
K5 is way larger compared to K-4, and we do not know the silo dia of the boomers. This particular bit of info will be kept secret throughout the batches.
 
On Navy Day 2024, Chief of the Naval Staff Admiral Dinesh K Tripathi says, "As far as the nuclear weapons are concerned, our stated policy is of no first use. And therefore the government had decided about the nuclear triad. The SSBNs provide that option for the third leg of the nuclear triad, which some people feel is the most reliable because it remains underwater and therefore not likely to be detected easily. We have obviously commissioned the second ship in August, and it is carrying out various trials, and then we'll do whatever she's supposed to do. And similarly, next one, in the coming months and years, it will be a part of our navy and provide the nation with an alternative for deterrence as also the second strive capability as part of a nuclear triad."




 
K5 is way larger compared to K-4, and we do not know the silo dia of the boomers. This particular bit of info will be kept secret throughout the batches.

We know the Arihant's, 1.4m. That's why we can fit in 3 K-15s or 1 K-4 per cell. At 1.6m, we can fit 4 in. And we know the K-4 is 1.3m.

If K-5 is more than 1.3m, then it's meant for the S-5. It's more prudent to believe S-4's also of the same size as Arihant.

I'd actually argue K-5 is the definitive model of K-4. Perhaps with MIRV, although it's more likely to carry 1 warhead and a bunch of decoys.

Another interesting concept. If the K-5 is 1.3m, the same as the K-4, and if we assume S-5 will have 2.5m cells, then it could end up carrying 3 K-4/5s per cell.
 
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We know the Arihant's, 1.4m. That's why we can fit in 3 K-15s or 1 K-4 per cell. At 1.6m, we can fit 4 in. And we know the K-4 is 1.3m.

If K-5 is more than 1.3m, then it's meant for the S-5. It's more prudent to believe S-4's also of the same size as Arihant.

I'd actually argue K-5 is the definitive model of K-4. Perhaps with MIRV, although it's more likely to carry 1 warhead and a bunch of decoys.

Another interesting concept. If the K-5 is 1.3m, the same as the K-4, and if we assume S-5 will have 2.5m cells, then it could end up carrying 3 K-4/5s per cell.
This figure is an estimate based on the triple k-15 adapter size, which actually itself is larger by design because the end rings and seals need to be several hundredfold bigger to be able to absorb the shock of the launch tube. This is very critical part which is why Arihant silo dia will remain a well kept secret so everyone has to second guess what is inside a particular sub while on patrol.

Btw the figures I quote are from the article section drawings of ANSP, not from any open source estimate. It is also needless to try and guess the next class silo dia, I am curious to find out whether they stretch that adapter rack again or not given K-15 is getting range extension.
 
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