INS Arihant (ATV) News and Discussion -2

[RayC]

cool down guys -there is enough religious sh-- all over the political spectrum -lets not put BR in that shit pan too

Arihant is a beautiful name and has no religious over tone as i look at it -lets keep it that way

OK.

it was named after my grandson, His name is Arahant.

And Sureesh Mehta is my coursemate!

To avoid charges of nepotism, he named it Arihant and not Arahant!

End of discussion!

[Drevin]

Its a 7500tonn SSBN/SSGN with submerged displacement of 9000-11700 tonns.and a length of over 110m with a diameter between 13-14m.Currently the boomer cum attack submarine is equipped with a low-powered( limitation is such that an efficiency factor of only 80% ) local built PHWR which can let the boy to speed upto 25 knots submerged.

ur posts r always unique.

Also, guru log .... 1m^3 = ? tons of displacement.

[Shankar]

Arihant -A displacement analysis

first the questions

the sumarine section which have been see by the press is the exposed part of the pressure hull and a very small part of the main ballast tank which surrounds the pressure hull and comes to play only when the ship submerges

The size of the main ballast tank and its diameter will depend on the fully loaded weight of the submarine and mostly under water at the time of the launch

So the diameter being referred to is the diameterof the pressure hull = 11 meter plus
add 2 meter on dia for the main ballast tank which surround the pressure hull below the water line '

we reach a figure of 13meter plus say 13.5 meter that is the diameter required for VM5/OK 650 reactor

The hull shape on top is some what flat where the crews have access to outside and also used during entering and exiting port .The hull starts bulging and curving out below the surfaced water line

that us why the sketches made during laucnh are not accurate and create confusion

you can guess the true dia of the submarine only when it is on surface fully exposed

cunning yindoos made sure no one gets that view by keeping it submerged during laucnh

[Philip]

Tx Igorr for clarifying the Brahmos size requirement which is why the Scorpene and Amur 950 cannot accomodate the missile.Sandeep in his IT feature has given the sub's reactor design as an indigenous version of the Russian "VM-4".Some sources give the Charlie-2 reactor designation as "VM-5" for a dpl. of 5400t.The same VM-4 reactor variants have also been used aboard the Victor series of attack subs,as well as Delta SSBNs (2).It appears to be a very successful type used over decades.Therefore,appropriately used for the Arihant also being of medium size around 6,000t.However,take a close look at the "MIKE" class,of which the Komsomolets was tragicaly stricken after an expolosion (torpedo compartment).The sub,meant to carry both torpedoes and cruise missiles with N-warheads too,was around 5750-t surfaced and upto 8,000t submerged.The Mike's dimensuons were also around the Arihant's given dimensions,120m L X 11m B.The Mike had an inner hull of titanium which gave her a terrific diving depth,far in excess of US subs.We have no idea if the Arihant is similarly builtit would be an expensive option,but a design detail that could be used in future subs if we have mastered titanium welding tech with Russian assistance and can afford them.The sail design of the Mike is similar to that sketched by Sandeep,also similar to other Russian SSBNs.Years ago,the IN was also supposedly impressed with the Sierra design.

PS:Glorious Jain culture! INS Arihant is well named.

The first sight of the unparalleled Mt.Abu temples is so unassuming that when one enters, one is struck speechless encountering the beauty equal to the Taj.I spent hours at the temple and along with my companions simply lying on the floor to marvel at the unequalled marble carved domed ceilings .I read many years ago that the sculptors used only abrasive cords to carve the sculptures,no chisels at all, and were paid by the amount of marble dust collected at the days end!

As for poor Oz,there only seaworthy Collins clas ssub conked out recently! Crossposted in the Intl.Navy thread.
http://www.abc.net.au/news/stories/2009 ... =australia

[Ashutosh Malik]

I would recommend Rear Admiral Raja Menon's take on the Arihant.

"Just One Shark In The Deep Blue Ocean
INS Arihant won’t end the N-submarine debate. It’s just started.
RAJA MENON"

http://www.outlookindia.com/article.aspx?261048

Best regards

[enqyoob]

1m^3 = ? tons of displacement.

If 1m^3 of water is displaced, u r pushing up/holding up 1m^3 of water, which has a mass of 1000 kilograms which is 1 Metric Ton (1MT) Generally close to weight of 2200 lbs.

So 1m^3 displacement = 1MT weight of submerged object. To float with 6000 MT displacement, the sub can weight only 6000 MT, and part of it may thus stick out. Then by adding load and by putting right amount of water in ballast tanks, the total weight is changed to whatever is the displacement of the whole thing when submerged. If more water gets in and cannot be pumped out, AhA! - what happened to PNS Ghazni (which also experienced vacuum inflation). Unlike winged aircraft which support their weight using aeroDYNAMIC forces (due to motion through air), submarines (and lighter-than-air airships) operate by hydroSTATIC forces, i.e,, buyoancy. So as soon as as someone publishes the precise exterior geometry, the max Displacement is known.

From the above discussions, I conclude that all pictures of subs in the open literature are bogus, except for this rare REAL picture of Pakistani submarine here - operated by Djinn Flying Carpet technology.

[kaangeya]

Australians live in latent fear of two IOR countries. India and Indonesia. All their antics will be trying to "counter-balance" perceived "threats" from those two countries, particularly since they see themselves as donning the mantle of the former colonial masters! It is more like the dog barking more than the master!

Oz foreign policy has been remarkably erratic for years neither self-centred nor idealistic. But being a huge richly endowed landmass in the middle of nowhere has allowed it to get away with big mistakes. Years of cozying up to Amrikhan interests - acting as a darwan in Vietnam, and then Indonesia etc., and also acting as a self-appointed chamcha of the Amrikhan caustically criticising India post-Pokhran in 1998 - led the nation nowhere. But these things made no difference to its security or well-being. But now from being an Amrikhan kooja, official Oz has become a rabid Chinese stooge with a severity that would make N.Ram blush, thanks to its new PM Kevin Rudd who is so deeply into this Chini-Chamcha thing that he is said- to get his L and R mixed up. Belatedly a few Oz liberals (ie the Labour Party supporters) are discovering that anti-Americanism doesn't mean much if it means becoming a Chinese stooge. After China arrested a Rio Tinto executive recently there is some questioning in Oz about what the heck is going on.

Ayesha Siddiqa can't have written that article, it must have been dished up by a badly trained copy editor taking down points from Dr.Siddiqa over the phone.

Bizarre science

This capability alone makes a nuclear submarine an extremely lethal weapon because it could sneak beneath a country’s territorial waters and fire a conventional or nuclear warhead. Also, since they are longer, nuclear subs can carry larger torpedo tubes that are useful for firing nuclear warheads.

Mixed, mangled, and mashed up metaphor

The real danger of the launch of a nuclear submarine by India is that it might force us to follow suit. If our admirals close their eyes they might just see their counterparts sticking out their tongues at them. This could prove to be a dangerous bait and bleed us financially.

[rakall]

..

self-deleted

[enqyoob]

The corollary to the "1m^3 = 1MT" fact is:

1. If you post the full contour, I can immediately calculate the MAXIMUM weight. The sub will not in fact go very close to this, because if it does, then the rate of diving/ coming up is greatly decreased. When the captain says, "SURFACE!" it may take a few days to do so because there is not much water to blow out of the tanks to increase buoyancy. But I can make my calculation of what is reasonable upward acceleration to maintain, so I can estimate the sub's ACTUAL max weight.

2. If you tell me its EMPTY displacement, or, better still, just allow me to see a photo of it sitting on the surface, I can figure out exactly where the water line is, so with that contour that you so kindly gave me, I can calculate its weight RIGHT THERE. If I know the maximum that it is ever seen above water, I know its empty weight - which means before weapons and other stores are loaded.

3. You have also told me how many weapon tubes it has, and what their sizes are. I know from elsewhere what missiles India has, and how big they are, and their range vs. warhead size.

4. So, with all this info, FOR ANY GIVEN MISSION, if my friendly Paki at the docks sends me a picture titled:

Arihant departs for mission

, showing it cruising out on the surface out of the harbor, then I can immediately tell what its weapon load is.

5. Now I go back to tsarkar's kind post:

Arihant is PURE SSBN! It will NOT carry ANY other weapons!

and my job is made easy. I know EXACTLY how many ballistic missiles are on board.

6. I plot the estimated cruise speed, and I can tell where it could have reached on any given day (esp. since missile range is not very large).

So I can estimate exactly which of my military installations are threatened, and so I have gained a great advantage in deciding exactly when to attack India.

7. I can also estimate exactly how many planes I need on patrol with hypersonic interceptors, or warships with ABMs, to counter the threat.

So, THANKS! tsalkal! You have been vely vely verly herpfur! The gleat Peopre's Lepubric thanks you!

But if Arihant is an SSGN with all sorts of multiple missions entrusted, this is not the case.

[enqyoob]

Thanks for the mention of "doubre shlouded ploperrel". Now I can estimate noise signature and propulsion efficiency much better!

[Drevin]

saar i don't know one bit of subs .... thanks for answering my question though. inquisitive student onlee.

[Arun_S]

I don't know why jingoes are obsessed with SSBN thingie, even only as an SSN it is a formidable asset. SSBN is required if the adversary has power to destroy a very substancial part of our land based nuclear assets in first strike. It does not seem that CHina has this power yet, so by the time they have this power, our SSBN fleet would be ready. Till that time we can use our SSN fleet to project power. If CHina tries any mischief, then its sea assets all over the world would be under threat by our SSN.

The above is a simplistic assessment that assumes a two-some engagement between India and another country.

The reality is something else; As Bhishma Pitamah of Indian strategic thinkers has often said in private communications that Indian nuclear confrontation is NOT a "Two-some game" I.e. is a four-some engagement, and then one can see that if there is a nuclear attack it will be a overwhelming first strike.

Here is an excerpt from the article "WAY TO A CREDIBLE DETERRENT © Arun Vishwakarma" in the January-09 issue of IDR:

Nuclear escalation with Pakistan can’t be considered in isolation. Pakistani nuclear weapons and posture is a proxy extension of China. As noted by senior Indian strategists that India-Pakistan nuclear scenario is not a two-some game. Meaning that in case of Pakistani first-strike the nuclear exchange will not be limited between India and Pakistan. A first-strike by Pakistan can only happen at Chinese behest , thus an Indian retaliatory second strike will be simultaneously addressed to Pakistan and China that unfolds into a wider and destabilizing scenario. Thus a nuclear retaliatory attack on China will involve Chinese taking down other challengers that will drag USA in the expanded nuclear exchange, with growing global destabilization. This could prompt global nuclear powers to destroy Indian nuclear capability by a collective first strike before India escalates and launch a second strike . India could thus be inviting a debilitating global strike even before it manages to launch a second strike. Thus Indian counterstrike has to be large dispersed force that can handle simultaneous threats from all directions and be unusually robust against simultaneous first strike by multiple nations.

These would require more, high yield payloads and long range delivery vehicles on survivable platforms. It would require MIRV development and fielding ATV and Agni-III class systems. The challenge to Indian diplomacy and the political class is to prevent the emergence of this situation. The main limitation to handle this situation is access to fissile material and the strength of the economy. Low cost technology initiatives to maintain this option are- regular PSLV launches of multiple satellites, production facilities for advanced fusion materials, a robust command and control system, and ballistic missile nuclear submarines

[vasu_ray]

I can also estimate exactly how many planes I need on patrol with hypersonic interceptors, or warships with ABMs, to counter the threat.

Are you implying that su-30mki with a load out of AAD and its subsequent versions can be in the air manning the coast during war time? cued by the ABM radars?

[negi]

Narayanan garu...so now we are not even spared in the MIL dhaga ? ,on a serious note do you really think discussing Arihant dimensions will compromise its mission or IN's capability ? specially when DDM has reported 'n' different versions and even estimates on BRF are mere speculations. I believe indulging in bit of Jingogiri is allowed...na ?

Coming to SSBN vs SSGN debate I believe we have to look at it from India's pov; unlike the P-5 India does not operate several N submarines and hence does not have a luxury of fielding dedicated SSN,SSGN or even SSBN's as of now . I am sure when push comes to shove ARIHANT will have to fulfill the role of a SSN for in absence of sister ships she will be all alone by herself and at the same time her small HUMP has enough stuff for enemy to classify it as a SSBN/SSGN type threat .

[Arun_S]

I would recommend Rear Admiral Raja Menon's take on the Arihant.

"Just One Shark In The Deep Blue Ocean
INS Arihant won’t end the N-submarine debate. It’s just started.
RAJA MENON"

http://www.outlookindia.com/article.aspx?261048

This is a very insightful and one of the best articles that I have read in a long time:

.... . . . . These problems bring us to the calamitous news that India does not have a ‘nuclear staff’. It has a strategic force commander (SFC) with his own strong staff, but the PM, the NSA, and the chairman COSC have no nuclear staff. This is because New Delhi is one of the few capitals of the world where turf battles don’t just end in bloodshed but in the annihilation of an entire group—the military, the only people with operational staff knowledge, annihilated by the victors, the N-physicists, bureaucrats, intelligence-wallahs and DRDO scientists.

The Arihant has a diameter of about 10 metres. Submarine diameters are the key dimension. The US, which has the best rocket technology, is able to put its 8,000-mile ICBM within a 12.8 metre hull. The Russians were unable to confine an ICBM within a 12-metre hull and so their missile tubes protruded two metres outside the pressure hull. The future of India’s nuclear submarine project is entirely in the hands of the rocket scientists. Even if they get 5,000-km (3,000-mile) missiles inside a 10-metre hull, it would be an ‘adequate’ success. In terms of diving depth, submarines built in India are not inferior to the average submarines being built abroad. So although the Arihant has captured the imagination of India as a missile-firing submarine, professionals everywhere in the world will want to know what India’s industrial achievements are in this project. Little noticed may be the fact that the Arihant will have an entirely Indian-designed sonar. Will the Chinese Jin class also have a Chinese sonar, or a reconstituted French one? Since India began building the ATV, submarine reactor design has leapfrogged. The British Astute class and the upgraded Los Angeles will all carry lifetime reactors, unlike the Arihant’s 10-year lifecycle power pack.

The media has enquired whether the Arihant will qualify India for the Security Council. A nuclear navy and an slbm second strike force will undoubtedly take us there, but we aren’t there yet. For a start, we now need to declassify the nuclear submarine project and either build a bigger yard to reduce the interval between boats or build on the west coast too. An slbm force can’t be less than six. Killer submarines cannot number less than eight for a country of India’s size. To build 14 subs from 2010 onwards at the current rate of accretion would take till 2038, by which time Arihant would be due for pension. This isn’t the path to the Council.

The government needs to write a white paper on India’s Nuclear Submarine Force, deploying for it a panel of strategists, industrialists and nuclear engineers, preferably with bipartisan political support. A number of issues need to be addressed, including the indigenisation of high-quality steel, advanced reactors, financial support, management structure, diplomatic cover for overseas deployment, the navy’s hrd and safety issues in Indian and foreign ports.

Only the professionals remember that the outstanding achievement of the US navy’s submarine fleet came from path- breaking management of the N-reactor, submarine construction and the missile programme. The heads of these programmes went on to become international figures, having pioneered many techniques used today in industrial management. Our expat community is being hired worldwide for their competence. So we surely don’t lack talent. Why can’t we hire the best Indians to manage a national project?

[John Snow]

With all humiity I think India can launch evey six months one hull for a submarine conventional or nuclear, If and only If the following entities get their act to gether (I am not including the Nuke power pack i.e. reactors)


Public Sectors
1) BHEL
2) HEC
3) HS & Garden Reach
4) BHPV
5) HMT
6) BEML
7) MEACON
8 ) MAZAGON DOCKS
9) INSTRUMENTAION iNDIA LTD (Pallakad Valves pumps etc)


CONTROL Systems & Instrumentation
1) IIL (Kota) I
2) BEL I
3) ECIL



there are many private sector leaders in weldment and welding electrodes and SPM suppiers.
to make this happen.

If only we could duplicate a Kalam saar to dedicate and develop vendors to deliver....

I wish I hd time to write up how rich and careless Indians are in squandering the installed capacity. THe cahps at Public sector gianst are squating flies when billions are sent away to other countries in the name of arms purchase.

There is no shortage of equipment, brains or technology, we dont have leadership or pride (enough) to move at the speed of business elsewhere...
BRF should have a thread for idea generation on how to bring about these industry giants to make a contribution to defense sectors.

[Rahul M]

Rahul – I view it as a pure strategic asset, ie, SSBN.

In my opinion, it will primarily be used to fine tune the subsystems and assist in developing an operational doctrine (political/military/strategic/tactical)
.................
India’s large number of survey ships will do route surveys in Arabian Sea, Bay of Bengal and the Indian Ocean. Mission planners will identify patrol billets for Arihant using the survey data. Thereafter Arihant will practice its tradecraft – stealthily carrying its package, avoiding detection and deploying it when ordered. In between, design flaws/enhancements will be identified and worked upon. And hone our political/military/strategic/tactical operational skills. Submarines are always single role ships. They’re dead meat in the hands of aircraft and surface ships if they try too many stunts. A non-swimout torpedo launch is a noisy affair and a dead giveaway from miles away.

insightful post. I had missed it yesterday.

might I ask what would be the minimum necessary to ensure 2 and 3 wrt PRC ?
how important is the 3rd leg of triad for us in ensuring this ?

Strategic deterrence for India, in my opinion, at a very basic and primitive level, will require –
1. Preventing a conventional war like 1962 by threatening a nuclear escalation (this is ruled out by our NFU policy).
2. Restricting a conventional war like Kargil by threatening a nuclear escalation (this was very successfully implemented. The Pakis couldn’t reinforce their logistics once India upped the stakes and they blinked first).
3. Prevent our opponents from using their nuclear weapon by threatening MAD.

[enqyoob]

negi:

Hi time the MILForum Mijjile Admira(tion)ls were subjected to some of the fine in-depth logic and reasoning of the BENIS dhaga. The sheer immaturity and indiscipline here would shock any mullah worth his 6 goats.

(OT)

Are you implying that su-30mki with a load out of AAD and its subsequent versions can be in the air manning the coast during war time? cued by the ABM radars?

I don't think it needs to be Su-30MKIs. My preference would be a set of large tanker/communication motherships of 777 / A380 class, cruising for say 10 hours on each patrol at 12,000 meters at say mach 0.8, each carrying, say, 4 small rocket/turboramjet Mach 3/ Mach 5 interceptors (carried under wings?) that can get up to 33,000 or maybe 40,000 meters, and each capable of launching 4 ABMs. With this, I believe that the defender has a huge advantage over any incoming BALLISTIC missile attack, because the reaction time to climb to 50,000 meters intercept is very short. Compare to all the ground-based stuff that is advertised, and u will c that this is the way to go. Curiously, NO ONE talks about this, which means that it must be the chosen way - it's the only way that ABM makes any sense except in a surprise / last-ditch desperate city defense. This in brief is why I say that the day of land-based ICBM mijjile, even with MIRV, decoys etc, is over. Its a dinosaur.

[a_kumar]

(BTW these DCNS guys should be punished in some way for arming Pakistan)

DCNS I thought until recently was old news, but seems like if Zardari has his way, they are back.

2-weeks old, but interesting article.. France and Germany "vie" to sell Pakistan subs

A "Thank You" card on its way to the 3.5 from PA (sorry.. from IDPs?) for the $1.5Billion

Pakistan appears to be losing patience with Germany over a deal worth some $1.5 billion to boost its 10-strong fleet of submarines, or it is playing a reluctant Berlin administration against Paris.

An agreement to supply three U-214 U-boats reportedly has been awaiting a final German signature since details were worked out in a visit to Germany by a Pakistani navy delegation in April. Quoting Pakistani government sources, the Financial Times Deutschland says President Asif Zardari may overrule his military's preference for the German subs to take up a "better offer" from France

One of those rare moments of sanity in the West..

In response to a preliminary inquiry in 2006, the Council gave a further sale of submarines to Pakistan a tentative green light. That approval raised a storm of political protest for fear that such a sale would add to the existing arms race between India and Pakistan. Last year a number of non-governmental organizations protested the supply to Pakistan of Drone aircraft and torpedoes. Pakistan is also interested in acquiring further German-made tanks and armored vehicles.

In Germany, concerns about supplying arms to Pakistan -- a nuclear power -- are increasing, attracting fears that the country could be destabilized by or even fall into the hands of militant Islamists. There are worries over the reliability of the armed forces with some element of the army said still to be sympathetic to the Taliban.

The issue is potentially divisive even within the governing coalition of Angela Merkel. In 2005 the Defense Ministry led by Franz Josef Jung -- a member of Merkel's center-right Christian Democrats -- negotiated a wide-reaching agreement with Pakistan to cooperate on armaments. A corresponding declaration of intent by the German government was blocked after opposition from Foreign Minister Frank Walter Steinmeier, a Social Democrat and his party's candidate to be chancellor at forthcoming elections, due on Sept.

With weapons for Pakistan currently a hot political potato -- and only likely to get hotter -- the Federal Security Council has deferred taking any decision on the sale, pending the election.

In the meantime, French do what they do best.

I take it Sarkozy attending the republic day parade (2008) and Manmohan attending the Bastille day Parade (2009) doesn't mean much.

The French have reportedly offered to supply three submarines and to sweeten the deal by upgrading and overhauling older submarines that are already part of the Pakistani fleet. Two years ago French President Jacques Chirac reportedly wrote a personal letter to Pakistan's president, Gen. Pervez Musharraf, urging his administration to buy French and offering the prospect of French government support and finance for new hotels and a car manufacturing plant.

And here comes the moment..

Meanwhile India is in the process of acquiring a nuclear submarine fleet using technology from France, joining the select club of countries with submarine nuclear capability.

[Igorr]

And here comes the moment..

Meanwhile India is in the process of acquiring a nuclear submarine fleet using technology from France, joining the select club of countries with submarine nuclear capability.

I call it 'journo-lamerism'

[a_kumar]

Meanwhile India is in the process of acquiring a nuclear submarine fleet using technology from France, joining the select club of countries with submarine nuclear capability.

I call it 'journo-lamerism'

Thats what I thought, when I posted the article.

But I am beginning to wonder if its psyops. Not sure what the source is, but are they trying to justify selling 3-more subs to Pakistan?

"Hey.. if we are helping India with Nuclear submarines, then why can't we make money selling 3-subs to Pakistan!!"

[Igorr]

But I am beginning to wonder if its psyops. Not sure what the source is, but are they trying to justify selling 3-more subs to Pakistan?
Hey.. if we are helping India with Nuclear submarines, then why can't we make money selling 3-subs to Pakistan!!"

yeah... it's very French

[Arun_S]

The submarine will carry four of an under-development submarine launched ballistic missile (SLBM) ‘K-X’ with 3,500-km range, each with several warheads called multiple independently targetable re-entry vehicles (MIRVs).

So K-X of only 3,500km range and MIRV is ab-initio version of Agni-3SL without the second stage. I.e. Agni-3SL's first stage and SUM stage along with MIRV payload.

Now that we know Arihant is 11 meter diameter (and not just 10 meter), thus including the hump behind the sail where the missile tubes are stowed, it is clear that there will be no 1.5 stage Agni-3SL but it will be full fledged Agni-3SL with 2.5 stages comprising:

• 1'st stage A3FS-S25
  2nd stage A3CUS-S4
  3rd stage A3SUM 100-10 (1.0m dia, 1150kg mass)

and the payload versus range is what I posted earlier.


It is clear that Indian warhead of ~550Kg is the most credible one that will be fielded on this craft. India must do what it takes to make, demonstrate and field credible light weight TN warheads for the Arihant to be meaningful by the time it enters service 2 years later. Right now the range at stuck with 1,650 Kg MIRV FBF warheads.

[rahulm]

spinrao,

Inox India Ltd is another excellent pressure vessel fabricator and a good candidate for submarine hull building. They compete aggressively and successfully with BHPV in the cryogenic storage segment. Infact, the design head is (at least until recently was) ex BHPV.

Inox have fabricated the cryogenic storage & lines for the SLP at Shriharikota http://www.inoxindia.com/jan081.html.

[John Snow]

Public Sector was listed.

Typical Dimensions of reactors as per FAS



**************
Russian Naval reactors table

MODEL POWER FUEL ENRICHMENT
(% Uranium-235) VESSELS
2 PWR*/VM-A 70 MWt 20% Hotel, Echo, November
1 PWR/VM-4 70-90 MWt 20% Charlie
2 PWR/VM-4 70-90 MWt 20% Victor II and III, Delta, Yankee
2 PWR/OK-650 190 MWt 20-45% Typhoon, Oscar
1 PWR/OK-650 190 MWt 20-45% Akula, Sierra, Mike
2 PWR/VM-5 m 177 MWt unknown Papa
2 LMR**/VT-1 73 MWt weapons-grade November 645
2 LMR/OK-550 or BM-40A 155 MWt weapons-grade Alfa
1 PWR/type unknown 10 (X-Ray) unknown X-Ray, Uniform, AS-12
2 PWR/KN-3 300 MWt unknown Kirov (battle cruiser)
2 PWR/type unknown 171 MWt unknown Kapusta (auxiliary ship)
2-3 PWR/OK-150 and OK-900 90 MWt 5% Lenin (icebreaker)
2 PWR/KLT-40 135 MWt up to 90% Arktika (icebreaker)
1 PWR/KLT-40 135 MWt up to 90% Sevmorput (auxiliary ship), Taymyr (icebreaker)

[Shankar]

ow that we know Arihant is 11 meter diameter (and not just 10 meter), thus including the hump behind the sail where the missile tubes are stowed, it is clear that there will be no 1.5 stage Agni-3SL but it will be full fledged Agni-3SL with 2.5 stages comprising:

1'st stage A3FS-S25
2nd stage A3CUS-S4
3rd stage A3SUM 100-10 (1.0m dia, 1150kg mass)

thanks Arun for clear presentation of ARIHANTS capabilities and agree with you as always it is meant to laucnh full sized Agni 3 SL and not sagarika as touted by the DDM

[Shankar]

1 PWR/OK-650 190 MWt 20-45% Akula, Sierra, Mike

-Arihant now thats our baby

[Singha]

would it be fair to say that due to physics and limitations of the power and drive train machinery, for
a give shape and size of submarine the increase in speed from adding a more powerful reactor curve tends to flatten out as the speed axis and power axis both increase. i.e beyond a point there is no point in adding a more powerful reactor?

that would imply a huge diff in top speed between say a 100mw and 190mw reactor but not so between
a 190mw and 300mw reactor (if anyone could fit it in same space) ?

there must be a sweet region in this curve that provides most bang for buck

[vavinash]

There was some news that the Agni-3SL had been tested once. Was it test fired using a pontoon launcher? When and where was this test done?

[Shankar]

would it be fair to say that due to physics and limitations of the power and drive train machinery, for
a give shape and size of submarine the increase in speed from adding a more powerful reactor curve tends to flatten out as the speed axis and power axis both increase. i.e beyond a point there is no point in adding a more powerful reactor?

the hydraulic drag do not increase linearly with speed and so the increment in power output of a reactor by 100% will not increase the submerged speed of the submarine by 100% but by say 50 % as a rough approximation . So in Arihant if we have a 80MW reactor the maximum speed will be around 25 knots submerged with 190 MW it will be close to 40 knots .The speed is also a function of shape and more importantly the shape of sail which generates maximum hydraulic resistance .Smaller the sail faster the sub will be with same reactor power output assuming the transmission gear have same efficiency over the entire power band

[Shankar]

ohio class can do 30 knots but at this speed its agulity is close to zero
la class does 35-40 knots and still retains its agility of sharp banking and cornering
virginai class also does 35-40 knots at full power but no so agile as la class

sea wolf class is the fastest till date at 40-45 knots on full reactor power and still retaining same degree of agility but not so muc as la class

akula 2 are generally assumed faster than la class at full power and alsmost as quite so I would assum Arihant will be doing 40 knots once in a while when in real danger

[Raj Malhotra]

Power & speed has a relationship of factor of three, i.e. to say power has to increase by power of three for increase in speed.

My guess is that Arihant has a backend of Akula mated to truncated front end of Borei

[Shankar]

now that Arihant is in water -our first priority should be to set up an extensive and robust communication infrastructure .This should include all of the following on a time bound basis
* Extreme-Low-Frequency, ELF 3-30Hz, submarine at depth
* Super-Low-Frequency, SLF, 30-300Hz, submarine at depth
* Ultra-Low-Frequency, ULF, .3-3KHz, submarine communications
* Very-Low-Frequency, VLF, 3-30KHz, submarine communications
* Low-Frequency, LF, 30-300KHz, atmospheric reflected communications
* Middle-Frequency, MF, .3-3MHz, long range strategic communications
* High-Frequency, HF, 3-30MHz, off-line-of-sight (OLOS) tactical ground communications
* Very-High-Frequency, VHF, 30-300MHz, ground-to-air and line-of-sight (LOS) tactical ground communications
* Ultra-High-Frequency, UHF, .3-3GHz, satellite and tactical ground-to-air communications
* Super-High-Frequency, SHF, 3-30GHz, satellite communications
* Extremely-High-Frequency, EHF, 30-300GHz, satellite communications
* Blue-Green-Laser-Frequency, BGLF, 625THz, submarine communications

[Shankar]

My guess is that Arihant has a backend of Akula mated to truncated front end of Borei

would like to agree with you on that say 70% akula 30% borei

[Austin]

Does any country uses Blue Green Laser for proper submarine communication ?
Or this is just myth

[Shankar]

to the best of my knowledge no country has yet perfected the green laser based communication system but as usal US is most advanced int he area.Company called Qpeak is supposed to give a technology demonstration on solid stet laser communicator some time later this year.The laser source brass board demo is scheduled for this year end followed by water cooling system for the brass board and air cooled amplifier module followed by simulated operation around 2011 .Si byt he time Arihant class is fully operational the green laser technology for sub surface communication as well as blue green laser technology for submarine detection may reach operational stage with US navy

[Shankar]

some more details

The Navy needs lasers for applications in high-data-rate communication between mobile platforms both above and below water. Given the transmissive properties of water and the desire to obtain large data rates, the lasers must operate in the blue-green wavelength region and be pulsed with nanosecond durations at rates ranging from 100's to 1000's of kHz. The nature of the communications operating platforms requires the lasers to be low in power consumption, small, lightweight, rugged and reliable. Q-Peak proposes to develop an innovative, scalable, all-solid-state laser configuration that will meet the stated requirements through a unique combination of components and technology.

http://www.navysbir.com/06_1/157.htm

[Shankar]

and others are in the fray too

A high efficiency, high power blue-green laser capable of providing short lses useful for underwater communication and detection systems. To provide the desired blue-green lasing, a solid state laser is pumped by a matched high-efficiency laser having a relatively long duration output pulses. Q-switching of the solid state laser is used to shorten the duration and increase the peak power of the pulses. Material found especially useful for practice of the invention are Holmium+3 and Praseodymium+3 as the solid state laser and a dye laser pumped by a mercury capillary lamp as the pumping laser.

http://www.freepatentsonline.com/4054852.html

[Shankar]

#

High-Power, Tunable Solid State Blue and Blue-Green Lasers

- Sponsor: Navy

- Objectives: Demonstrate high-power blue-wavelength source for non-acoustic underwater sensing and communications.
http://www.psicorp.com/locations/sub_qpeak.shtml

this technology surely even they will not give to thier newest ally -we need to develop ourselves and quickly -no point in having anuclear sub and making it vulnerable everytime it comes up near surface to communicate

[Shankar]

Just for you Austin - current level of research in India

For the specific purpose of satellite to submarine communication where the
requirements for the laser are very demanding two special types of excimer lasers are
being developed4. One is the Raman shifted Xe CI laser and the other is the Hg,
Blue Green Lasers 187
BrlHgBr dissociation laser. Theselasers are designed to give multi joule output
(1-10J pulse) at a rep rate exceeding 100 Hz with high efficiency (> 1% overall) and
long operating life (MTBF > 10,000 hrs).
Xe CI laser has been operated to give 5-10 J per pulse at 308 nm with 2-4%
efficiency utilising X-ray preionisation or electron beam pumping. A very narrow
line width of 0.01 5 nm is possible with injection locking and more than a million
shots can be obtained before the power drops to one half. To obtain output in the blue
green, the UV output at 308 nm is down converted to 459 nm in single step Raman
shift in lead vapour and to 500 nm in 3 step process in molecular hydrogen.
Stimulated Raman conversion to 459 nm has been demonstrated with overall efficiency
of 40 to 50%. The lead vapour Raman active cell however has to be operated at
1200°C to 1300°C. Long time operation of this cell is still a problem. The hydrogen

Raman medium however can be operated at room temperature and net efficiency of
30% for the third stokes radiation has been observed. Raman down conversion of
the UV to blue green is an area of current interest and experimentation is in progress
to improve the performance.
The HgBr dissociation laser giving output at 502 nm and 504 nm is the most
promising of the high power blue green lasers. Its operation (Fig. 3) is similar to the
Figure 3. Energy levels for the Hg Br,!HgBr dissociation laser.
rare gas halide excimer in which the excited state is strongly bound while the ground
state is only weakly bound. However the difference lies in that the ground state HgBr
does not dissociate but rather combines with bromine atoms to form Hg Brz with a
high probability. Pumping is through the dissociation of the stable molecule
HgBr, by electron impact in the electric discharge. Using UV preionisation lase^
output upto I J/liter with lo/, overall efficiency in a 100 cm3 volume has been obtained.
Line width of 0.05 nm with injection locking is possible. The laser medium is
corrosive but an operating life of million shots to half power is available. Further
development is aimed to upscale the pulse energy, efficiency and operating life.

http://publications.drdo.gov.in/gsdl/co ... ir/doc.pdf