Indian Naval Discussion

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Nick_S
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Re: Indian Naval Discussion

Post by Nick_S »

SNaik wrote:Jesus, these effing journalists. The fireclay bricks themselves were ok, the material which was used as lining between the boiler surface and the bricks and as stick-together didn't stand the heat.
Was that the same insulation material which was shown as burning a couple months ago in Oleg's pic?
Last edited by Nick_S on 23 Sep 2012 17:05, edited 1 time in total.
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Re: Indian Naval Discussion

Post by adityadange »

John wrote:INS Makar has been commissioned
Image
Photo: Livefist
from the article "The ship is propelled by four Cummins engines as well as two bow thrusters."
can anybody tell me what exactly is this?
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Re: Indian Naval Discussion

Post by Bihanga »

pandyan wrote:What a beautiful ship!
The vessel is indigenously built by Alcock Ashdown Gujarat Ltd.
Image
Cannot believe my eyes, is it Made in India vessel!
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Re: Indian Naval Discussion

Post by kmc_chacko »

:D :D
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Re: Indian Naval Discussion

Post by SNaik »

Nick_S wrote:
SNaik wrote:Jesus, these effing journalists. The fireclay bricks themselves were ok, the material which was used as lining between the boiler surface and the bricks and as stick-together didn't stand the heat.
Was that the same insulation material which was shown as burning a couple months in Oleg's pic?
No that was before trials IIRC. Fuel residue burning in exaust pipe.
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Re: Indian Naval Discussion

Post by SKrishna »

Austin wrote:Bricks, destroying trials of "Vikramaditya", made ​​in China
Dyachkov announced that the repair will be completed in May 2013, and the deadline ship, according to preliminary data, will move to nine months. Official data on the cost of repairs were not called.

"The boilers were manufactured at the request of the Indian side in the Russian Navy used boilers, which are used as fuel oil. Indian side has made a request to use boilers that run on diesel fuel," - said Dyachkov meeting with Deputy Prime Minister Dmitry Rogozin, dedicated situation with the aircraft carrier.

According Djachkov work Boiler Design Bureau was conducted in the Russian Federation, and the boilers were manufactured at the Baltic Shipyard. "During the trial in the vessel wall boilers are not technically able to develop full speed. They were tested for a maximum capacity of 40%. When first entering the large capacity of up to 100% was observed partial collapse of refractory masonry in boiler furnaces," - he said.

Responding to a question Rogozin, which used materials Dyachkov said that it was "fire clay bricks made in China." "Unfortunately, the Russian production of this material has been lost," - declared the president of USC.
We have excellent refractory brick manufacturing facilities in India. Not sure why Chinese refractory bricks where chosen (cheaper)?
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Re: Indian Naval Discussion

Post by John »

adityadange wrote: from the article "The ship is propelled by four Cummins engines as well as two bow thrusters."
can anybody tell me what exactly is this?
As name implies they are thrusters on bow of the ship allowing it quickly turn.
The Hindu article has good picture of it

Image
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Re: Indian Naval Discussion

Post by RajD »

vasu raya wrote:On second thoughts, the 50 sub idea might be a phishing probe on an open forum since such large fleet would threaten or tax US sub resources in trying to keep track of them, so denial of reactors might also be on NPA's (a mask) agenda especially the Thorium ones since nuclear fuel isn't a constraint there anymore

Is Kudankulum related to any of this technological development path?
O/T on this thread but
The main reactor at Kudankulam uses Russian designed WER-1100 model with enriched Uranium and as source and an advance safety feature like passive heat removal. But what you say might be very much on cards because earth crust in the southern Indian peninsula is suppose to contain Thorium reserves sufficient for eon years to satisfy Indian needs for cheap and clean( less hazardous regarding nuclear waste management) electricity. Of late, Indian nuclear research is .concentrating heavily on Thorium based reactors and its fruition might be few decades away.
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Re: Indian Naval Discussion

Post by RajD »

[quote="RajD"]
The main reactor at Kudankulam uses Russian designed WER-1100 model /quote
Correction: It is V V E R -1000.
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Re: Indian Naval Discussion

Post by VinodTK »

Cross Posting from the Army news thread

Forces mulling 3 joint commands
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Re: Indian Naval Discussion

Post by SNaik »

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Re: Indian Naval Discussion

Post by adityadange »

cross posting from chinal military watch thread:
vina wrote:
Singha wrote:aye, once it gets the MFSTAR and barak8 arrays, will kick the behind of anything except the Type45(if they fund its full armament ever) and the Aegis/Kongo/Sejong troika.
Well. dunno. The Kolkata is a "finer" ship. Similar length as other two but with around 2000 ton less displacement from a smaller beam and hence "finer" and more hydrodynamically efficient.

Also, the has better anti ship capabilities than either with the Brahmos I think. The Japanese ship doesn't have a land attack capability at all , and carries no helo and hence rather limited in anti sub. The Korean ship does carry two helicopters like the Kolkata though.

Type 45 is most similar to Kolkata and has great anti air, decent anti sub, and limited anti ship. but no land attack. So from the looks of it, the Yindoo Banias seem to have packed a decent armament fit with nice all round, anti air, ship , sub and land attack capability, into a thin starving hull form!

The only quibble I have is with the Ukranian/ dated ex soviet power plants. The Type 45 does have a more upto date propulsion concept. But then, hey, what is the point in just getting there, if you dont have the armement eh, Brittania ?
if kolkata class is 2000 ton lighter that others, would there be compromise on ship strength? how much damage will a missile will cause to the ship compared to the heavier ones? or is it that we are using better metals?
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Re: Indian Naval Discussion

Post by Sabyasachi »

adityadange wrote:
if kolkata class is 2000 ton lighter that others, would there be compromise on ship strength? how much damage will a missile will cause to the ship compared to the heavier ones? or is it that we are using better metals?
Staying power is proportional to the cube root of displacement.
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Re: Indian Naval Discussion

Post by SNaik »

Sabyasachi wrote:Staying power is proportional to the cube root of displacement.
That statement is statistically valid for warships of less than 7000 tons displacement. More accurately, the staying power of small combatants against anti-ship missiles varies with the natural logarithm of the full load displacement.
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Re: Indian Naval Discussion

Post by John »

Putting the reply here
akshat.kashyap wrote:^^^

Kolkata class will not wait for LR-SAM to be operational, only launchers will be fitted for now. Missile test will happen afterwards, once it will be ready.
Where did you hear that from what i understood LR-SAM has undergone a few successful tests but it is integration with P-15A that is still a question mark, so in other words the launchers, fire control that is still not yet been hashed out and is holding up Kolkata?

The only quibble I have is with the Ukranian/ dated ex soviet power plants. The Type 45 does have a more upto date propulsion concept. But then, hey, what is the point in just getting there, if you dont have the armement eh, Brittania ?
Yes propulsion system is quite dated (but i don't think we have solid information on that yet) compared to even Shivalik which uses more modern and quieter design hopefully we address that with P-15B, i think it goes back to lack of many designs in that 8000 ton compared to 5000 ton category and Russians are relatively behind in that category till they come up with their own next generation destroyer.
if kolkata class is 2000 ton lighter that others, would there be compromise on ship strength? how much damage will a missile will cause to the ship compared to the heavier ones? or is it that we are using better metals?
IMO Final displacement of P-15A should be around 8000+ tons i would take the current projections' with grain of salt. I predicted P-17A will be around 6000 Tons full load (compared to projection of 4500 Tons) and i was wrong it was over that :lol:.
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Re: Indian Naval Discussion

Post by Shyam_K »

John wrote:
adityadange wrote: from the article "The ship is propelled by four Cummins engines as well as two bow thrusters."
can anybody tell me what exactly is this?
As name implies they are thrusters on bow of the ship allowing it quickly turn.
The Hindu article has good picture of it

Image
The picture seems to shows the outlet of the bilge pump. The bow thrusters would be below the water line.
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Re: Indian Naval Discussion

Post by Singha »

given the massive size of the ship fitting out it wouldnt be surprising if P15A weighs in @ 9000t full load.
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Re: Indian Naval Discussion

Post by Austin »

If the displacement of ship goes high then what it is designed for then it will impact its fuel economy , top speed and even perhaps its sea keeping qualities , there might be some design reserves but not beyond a point.

I think they maintained the same engine for P-15 ,A & B for logistical reason , the same will go for P-17 class.
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Re: Indian Naval Discussion

Post by Eric Leiderman »

http://www.flightglobal.com/news/articl ... ms-370233/

BAMS would be particularly useful for India because it is optimised to operate in conjunction with the Boeing P-8A Poseidon, of which India has ordered eight examples designated as the P-8I Neptune
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Re: Indian Naval Discussion

Post by Eric Leiderman »

Shyam_K

The water coming out of the bow will be for the bow thrusters, sea water cooling.Bilge pumps do not pump overboard any more, the water is processed and once below a certain contamination level is reached, it is pumped overboard.
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Re: Indian Naval Discussion

Post by John »

Austin wrote:If the displacement of ship goes high then what it is designed for then it will impact its fuel economy , top speed and even perhaps its sea keeping qualities , there might be some design reserves but not beyond a point.

I think they maintained the same engine for P-15 ,A & B for logistical reason , the same will go for P-17 class.
Austin,
Isn't it CODAG propulsion system (Bergen Diesel +Gas turbines) which should have excess of 70k Hp which is enough to push vessel that size.
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Re: Indian Naval Discussion

Post by member_23360 »

John wrote: Where did you hear that from what i understood LR-SAM has undergone a few successful tests but it is integration with P-15A that is still a question mark, so in other words the launchers, fire control that is still not yet been hashed out and is holding up Kolkata?
http://www.business-standard.com/india/ ... es/485383/

Meanwhile, three Kolkata-class warships which were to be fitted with these are held up, incomplete in Mazagon Dock Ltd, Mumbai (MDL). The shipyard is hoping for launchers (without missiles) to be delivered soon, so that construction can continue. The missiles could be delivered subsequently, even after the Kolkata-class destroyers enter service with the Navy.
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Re: Indian Naval Discussion

Post by John »

Yea akshat that is what i was saying it is LR-SAM launchers that is currently holding back P-15A.
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Re: Indian Naval Discussion

Post by Austin »

Rogozin: Vikramaditya Broke Down Due to Poland and British Equipment
During sea trials of aircraft carrier INS Vikramaditya upgraded in Russia for Indian Navy, serious failures were found in some systems produced in Poland and Great Britain, said Russian vice premier Dmitry Rogozin.

"Some defects were revealed in aggregates delivered by Poland and Britain. But aircraft flight tests passed successfully", Rogozin posted on his Facebook page.

Earlier on, president of United Shipbuilding Corporation (USC) Andrei Diachkov reported to Dmitry Rogozin on the situation around the ship. According to him, Chinese materials were used when assembling of boilers for the carrier. "The boilers were made on India's design. In Russian Navy, we use oil-fired boilers. But Indian partners wanted us to make boilers working on diesel fuel", reports Interfax citing Diachkov.

Answering Rogozin's question what materials were used for thermal insulation, Diachkov said that "fireclay bricks were made in China". "Unfortunately, Russia has lost production technology of that material", added the USC director.

As for him, boilers cannot work in full swing during dockside trials at the shipyard's mooring quay. "They were tested at 40% power", Diachkov said.

When the carrier reached full power for the first time at sea trials, fireproof brickwork in boiler furnaces was partially destructed, said the USC director.

"Alternatively disabling each boiler, we repaired the brickwork during sea trials, but nonetheless it broke again after next trial run at high-power modes", he noted.

Diachkov added that boiler installations used in Russian ships were insulated with asbestos boards; Indian party wanted this material to be excluded.

Trials of the aircraft carrier held in the White and the Barents seas revealed new defects, said Diachkov.

"There are some other broken down systems, including those purchased from NATO countries. They are three refrigerating machines, nitrogen generators and other equipment. Suppliers were offered by Indian side", Diachkov stressed.

He also pointed out that repair of INS Vikramaditya was planned to finish by May 2013.
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Re: Indian Naval Discussion

Post by vina »

adityadange wrote:if kolkata class is 2000 ton lighter that others, would there be compromise on ship strength? how much damage will a missile will cause to the ship compared to the heavier ones? or is it that we are using better metals?
I am not sure what you are asking here. Rather than structural failure, it is flooding damage that sinks ships in nearly all cases. Surviving flooding damage goes back to how the hull is subdivided and that of course feeds back into strength.

Commercial ships are designed such that the ship continues floating and has enough freeboard even if a bulkhead is breached such that two adjacent compartments flood. Warships will have more stringent standards to take battle damage.

Look up this pic of Kolkata Class under construction. You will see longitudinal bulkheads in addition to transverse bulkheads being built. In commercial ships, you will rarely if ever see longitudinal bulkheads.

That said, the Kolkata (going by Delhi class dimensions, must be the same.. given that it is a Delhi class follow on with better weapons and stealth) at a draft of 6.5m is a pretty "deep" ship and deeper the ship, stronger it is (depth of beam is a key determinant of strength).
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Re: Indian Naval Discussion

Post by vina »

John wrote:Isn't it CODAG propulsion system (Bergen Diesel +Gas turbines) which should have excess of 70k Hp which is enough to push vessel that size.
Per what I read, it has the same propulsion system (and indeed same hull form) as the Delhi class which is COGOG with Ukranian Zorya gas turbines (4 nos, arranged in pairs)
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Re: Indian Naval Discussion

Post by vina »

John wrote:IMO Final displacement of P-15A should be around 8000+ tons i would take the current projections' with grain of salt. I predicted P-17A will be around 6000 Tons full load (compared to projection of 4500 Tons) and i was wrong it was over that :lol:.
No. I don't think so. It is the same hull as the Delhi class and is just a derivative of that with a stealthy superstructure and a better weapons fit (Brahmos instead of the Uran/Switchblade and Barak-8 instead of Shtil) and far better Radars. Kolkata will be approximately Delhi's displacement as well.
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Re: Indian Naval Discussion

Post by vina »

Singha wrote:given the massive size of the ship fitting out it wouldnt be surprising if P15A weighs in @ 9000t full load.
Kolkata has the same hull as the Delhi class (same length, breadth, draft(my guess from wiki) and displacement!). It looks like a duck, squawks like a duck, walks like a duck and hence , well, it is a duck! So, the Kolkata too will come in at Delhi's displacement. Wont grow to some 2000 tons overweight. Very little risk here, it is a derivative design.

Austin wrote:If the displacement of ship goes high then what it is designed for then it will impact its fuel economy , top speed and even perhaps its sea keeping qualities , there might be some design reserves but not beyond a point.

I think they maintained the same engine for P-15 ,A & B for logistical reason , the same will go for P-17 class.
Delhi and Kolkata have the same power plants Ukranian (COGOG). Shivalik (P17) have LM2500+ Diesels (CODOG).

That said, I did a quick math for the Shivalik vs Delhi/Kolkata hull forms

[code]
Length Breadth Draft Displacement Blk.Coeff
Shivalik 142.5 16.9 4.5 6200 0.558
Kolkata 163 17.4 6.5 7000 0.370
[/code]


Kolkata is longer than the Shivalik by 20m, has nearly the same breadth and is 2 ms greater draft. The Shivalik is a stubbier ship (lower L/B.. bad for hydrodynamic efficiency) and less deep (higher B/T.. bad for structural strength) than the Kolkata! Just look at the block coeff. The Kolkata has a block coeff of only 0.37! The Kolkata /Delhi are obviously great hull forms and the Delhi's experience would have convinced the IN to persist with those/
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Re: Indian Naval Discussion

Post by Pratyush »

^^^

Regardless of the merits of the hull form and power plant. It is incumbent upon the GOI to order at least that many ships that make it possible for the IN to stare down the PLAN. Protecting Indian maritime interests wherever they may be. While retaining control of the escalation ladder.
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Re: Indian Naval Discussion

Post by adityadange »

vina wrote: I am not sure what you are asking here. Rather than structural failure, it is flooding damage that sinks ships in nearly all cases. Surviving flooding damage goes back to how the hull is subdivided and that of course feeds back into strength.

Commercial ships are designed such that the ship continues floating and has enough freeboard even if a bulkhead is breached such that two adjacent compartments flood. Warships will have more stringent standards to take battle damage.

Look up this pic of Kolkata Class under construction. You will see longitudinal bulkheads in addition to transverse bulkheads being built. In commercial ships, you will rarely if ever see longitudinal bulkheads.

That said, the Kolkata (going by Delhi class dimensions, must be the same.. given that it is a Delhi class follow on with better weapons and stealth) at a draft of 6.5m is a pretty "deep" ship and deeper the ship, stronger it is (depth of beam is a key determinant of strength).
Thanks vina for your post. What I want to say is if the hull is made 1 inch thicker it will add substantial weight to the ship. This may sound silly but I was under impression that warships hulls are made up of thick metal plates to protect from misile/torpedo attack (similar as of a tank although not as thick as a tank). And thicker the hull, better the protection. Also if the explosion makes bigger hole then chances are more to sink as more water gets inside the ship.

Here I am not able to get your theory of "deeper the stronger" ship. Can you please explain why a deeper ship is considered stringer? Again this creates a new question that wouldn't it make difficult to operate a deeper ship near coasts?
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Re: Indian Naval Discussion

Post by SNaik »

John wrote:Yea akshat that is what i was saying it is LR-SAM launchers that is currently holding back P-15A.
http://defense-update.com/20111121_bara ... -2012.html
This report from last November expects launch tests in Feb 2012. No indications that the tests have been conducted. Insofar Barak 8 has had just two confirmed launches back in 2010 both in the basic configuration without the booster.
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Re: Indian Naval Discussion

Post by Singha »

Hopefully bigger hull in the p15b atleast. Make it a strike cruiser of sorts with a huge 72 cell barak8 loadout ....keep 1 heli and pack the sides with decoys and barak1 cells
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Re: Indian Naval Discussion

Post by John »

vina wrote:Kolkata has the same hull as the Delhi class (same length, breadth, draft(my guess from wiki) and displacement!). It looks like a duck, squawks like a duck, walks like a duck and hence , well, it is a duck! So, the Kolkata too will come in at Delhi's displacement. Wont grow to some 2000 tons overweight. Very little risk here, it is a derivative design.
Super structure, mast and weapons load will definitely lead to higher displacement than Delhi, just look P-17s based on original projections of stretched talwar with some changes the displacement was projected around 5000 Tons but few changes here and there brought it to around 6200 tons. I know we had similar debate back then when i said P-17 displacement will be much higher than current projections, will know in time if same is true.
vina wrote:Per what I read, it has the same propulsion system (and indeed same hull form) as the Delhi class which is COGOG with Ukranian Zorya gas turbines (4 nos, arranged in pairs)
For some reason the sites quoting Kolkata specs seem to list Bergen diesel engines?
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Re: Indian Naval Discussion

Post by Sabyasachi »

SNaik wrote:
Sabyasachi wrote:Staying power is proportional to the cube root of displacement.
That statement is statistically valid for warships of less than 7000 tons displacement. More accurately, the staying power of small combatants against anti-ship missiles varies with the natural logarithm of the full load displacement.
It is a generic/rough model based on relationship between displacement, yield of ordnance hitting the ship and the probability of ship suffering mission kill. Its valid for all types of man-of-war and all types of attack implausible. Study to reach that conclusion was based on probability model using a numerical maximum likelihood estimate. The highest displacement study was Lexington ship with 47770 tons of displacement damaged during coral sea battle world war II.

The point another poster mentioned is correct but too difficult to comprehend for layman like me because complete modelling of any ship, its survival mechanisms in design (stealth), speed, battle zone awareness and surface reaction to ordnance detonating within the platform or outside is required to predict its staying power.

If you can not do extensive modelling of the ship and its systems, then bigger is better; both ship and ordnance :) .
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Re: Indian Naval Discussion

Post by SNaik »

Sabyasachi wrote:The point another poster mentioned is correct but too difficult to comprehend for layman like me because complete modelling of any ship, its survival mechanisms in design (stealth), speed, battle zone awareness and surface reaction to ordnance detonating within the platform or outside is required to predict its staying power.

If you can not do extensive modelling of the ship and its systems, then bigger is better; both ship and ordnance :) .
I was referring to AN ANALYSIS OF THE HISTORICAL EFFECTIVENESS OF ANTISHIP CRUISE MISSILES IN LITTORAL WARFARE by John C. Schulte, Naval Postgraduate School, Monterey, September 1994. This research is de-classified and available in the Web.
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Re: Indian Naval Discussion

Post by vina »

John wrote:Super structure, mast and weapons load will definitely lead to higher displacement than Delhi, just look P-17s based on original projections of stretched talwar with some changes the displacement was projected around 5000 Tons but few changes here and there brought it to around 6200 tons. I know we had similar debate back then when i said P-17 displacement will be much higher than current projections, will know in time if same is true.
Talwar dimensions - L*B*T is 124.8*15.2*4.2 Displacement is 4200t
Shivalik - L*B*T is 142.5*16.9*4.5 , Displacement is 6200 tos

So, from talwar to Shivalik, L grows 14.18%, B grows11.18%,T grows 7.14%, while displacement grows a whopping 53.6% .

The block coeff of the Talwar is 0.4940, while for the Shivalik is 0.55. No way the Shivalik is a "stretched" Talwar. It is a new design alright with a basically new hull form. Every dimension has grown apperciably and most importantly , the Shivalik is a "fuller" ship than the Talwar.

That is not the case from the Delhi to Kolkata. The hull is exactly the same. The extra weight if any will be well within design tolerance. I really see no case for growth in weight like the Talwar to Shivalik here. The basic dimensions remain exactly the same!
vina wrote:Per what I read, it has the same propulsion system (and indeed same hull form) as the Delhi class which is COGOG with Ukranian Zorya gas turbines (4 nos, arranged in pairs)
For some reason the sites quoting Kolkata specs seem to list Bergen diesel engines?[/quote]
Those Bergen diesels are for hotel load, not propulsion.
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Re: Indian Naval Discussion

Post by vina »

adityadange wrote:Thanks vina for your post. What I want to say is if the hull is made 1 inch thicker it will add substantial weight to the ship. This may sound silly but I was under impression that warships hulls are made up of thick metal plates to protect from misile/torpedo attack (similar as of a tank although not as thick as a tank). And thicker the hull, better the protection.
It is 2012 and not 1932 and these days , no ship, including capital ships are armored like the capital ships of yore! The days of ship slugging it out with large caliber guns (each salvo from all the guns would cumulatively launch the weight of a maruti 800 therabouts in the air in shell weight) are over. With that, the armor on the ships went the way of the dodo!
Here I am not able to get your theory of "deeper the stronger" ship. Can you please explain why a deeper ship is considered stringer? Again this creates a new question that wouldn't it make difficult to operate a deeper ship near coasts?
Oh, basic structures. Think of the ship as a box girder with the ends closed, supported on water (with max bending moment with the ship suspended on wave crests at the ends and the middle in the trough (sort of like a girder suspended on two points). Now a deeper girder has a has a stronger resistance to bending than a shallow girder.
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Re: Indian Naval Discussion

Post by SaiK »

http://www.bharat-rakshak.com/NEWS/news ... wsid=19656
At present, ICG is making do with just about 110 ``surface units'', including just six advanced and 11 other offshore patrol vessels, and 51 ``air units'' comprising 28 Dornier surveillance aircraft, 19 Chetak and four Dhruv helicopters.
Actually we need our dhruvs equipped with ASW devices and weapons, as new age drug cartels are using advanced mini submarine vehicles to ship drugs around the world.
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Re: Indian Naval Discussion

Post by nachiket »

vina wrote: Talwar dimensions - L*B*T is 124.8*15.2*4.2 Displacement is 4200t
Shivalik - L*B*T is 142.5*16.9*4.5 , Displacement is 6200 tos

So, from talwar to Shivalik, L grows 14.18%, B grows11.18%,T grows 7.14%, while displacement grows a whopping 53.6% .
That begs the question. If the size has increased substantially, why is there no substantial increase in the armament? In layman terms, what is the use of a significantly bigger ship if it doesn't carry more missiles?
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Re: Indian Naval Discussion

Post by Viv S »

What's the general opinion on the forum about India joining the Global Combat Ship program proposed by the UK, with Brazil and Australia in tow? Perhaps even a few others in a peripheral role; Malaysia and Canada come to mind. As a follow-on to the P-17A.


Unlike some of our other 'joint programs' where we just seem to be along for the ride (PAK-FA, MTA), warship design and construction is one field where India is at the leading edge of modern technology. That said, the price differential that we take for granted with Indian products appears to shrinking as far as naval ships go. Certain components are likely to remain imported even in 2020; the power plant being one, the main gun being another. Might help to buy in bulk. It will take some effort to harmonize multinational service requirements (the NFR-90 splintered because of different expectations), but in general there doesn't appear to be any major divergence in the approach towards building a stealthy warship. The FREMM would have been worth looking into, but it seems to be at a significantly more advanced stage of development than the GCS (which is still in the preliminary design stage).

Just to clarify I'm suggesting a collaboration on building similar but not identical ships - sensor and weapons suites will obviously vary widely with nation (Aster 30+Storm Shadow/LRSAM+Nirbhay/ESSM+Tomahawk) but I'd think it should be possible to retain enough commonality to lower the costs vis-a-vis an entirely indigenous design (albeit with significant imported content).
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