Kalvari Class Submarines - Updates & Discussions

randomradio

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Nov 30, 2017
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P75I must be enhanced scorpene.Barracuda shortfin is too costly .We dont need more types and repeat current mess.Only reason i guess current order of 6 was not extended was data leak.

I think they are waiting for DRDO to finish development of the AIP before adding the last 3 to the Scorpene order.
 
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_Anonymous_

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Dec 4, 2017
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Barracuda is too costly and not optimized for shallow waters.
Enhanced scorpene is the choice for commonality and cost.
If we want brute ability choice is german type 216,its optimized for shallow waters,is the quietest and the best capability wise.But also costly and will require a new infra setup.
I didn't get your point. There are Kilos & HDW for all through the 2030 - 35. Let's assume these are for the littoral waters. The Scorpenes for immediately beyond that & the SSN's for the IOR.

When the Kilos & HDW retire, we can press the Scorpenes into their role, the Barracudas for an intermediate role.

Why go in for a separate design and complicate the logistics?
 

Austerlitz

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Jun 2, 2018
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I didn't get your point. There are Kilos & HDW for all through the 2030 - 35. Let's assume these are for the littoral waters. The Scorpenes for immediately beyond that & the SSN's for the IOR.

When the Kilos & HDW retire, we can press the Scorpenes into their role, the Barracudas for an intermediate role.

Why go in for a separate design and complicate the logistics?

HDW will be done by 2030.By 2030 you will have around 5-6 kilos left on their last legs and obsolete.
I advocate either enhanced scorpene if we want cost cut and commonality or type 216 if we want capability.Either will do.
Barracuda is too costly and still not as good as type 216 for shallow waters of arabian sea and bay of bengal.
The budget allocated is around 1.1 billion per boat,you cant get barracuda for that.
 

randomradio

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Nov 30, 2017
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Barracuda is too costly and still not as good as type 216 for shallow waters of arabian sea and bay of bengal.

Dunno why you say that.

The budget allocated is around 1.1 billion per boat,you cant get barracuda for that.

In case they need to exceed budget, they can do that, it's not such a big problem for strategic programs. It's non-strategic programs that suffer from such redlines, like the refuellers contract. When it comes to strategic programs, capability is of greater priority than budget.
 

sid4587

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Dunno why you say that.



In case they need to exceed budget, they can do that, it's not such a big problem for strategic programs. It's non-strategic programs that suffer from such redlines, like the refuellers contract. When it comes to strategic programs, capability is of greater priority than budget.
Yes and moreover instead of 6 we can have 4 with france assistance and rest we can build, i mean that kind of negotiation can happen. But if the thing is that it wont run in shallow water then no use. Experts can comment more on that. And as far as barracuda being costly we dont know that yet bcz so far conventional version is not yet priced for any country, correct me if i am wrong.....
 

Gautam

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Operational air-independent propulsion for Kalvari submarines: A critical technology for underwater stealth

By: Huma Siddiqui | New Delhi | Updated: November 11, 2019 6:52:37 PM

The Made in India AIP system is therefore already planned to be retrofit onboard first submarine which enters a major refit. The indigenous AIP system is still at a developmental stage whilst pending four Submarines under the project are scheduled for commissioning in the next two years.
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Kalvari class submarines are powered by conventional diesel-electric propulsion systems, as per the original plans, the last two submarines were to be equipped with an indigenously developed AIP technology Photo courtesy: Indian Navy.

The recent announcement by Defence Research and Development Organisation (DRDO) about the Land-Based testing of the indigenous Air-independent Propulsion (AIP) is going to take time before it gets operationally ready to be fitted on the submarines of the Indian Navy.

Before a Defence Quality Assurance (QA) approved ‘productionised’ version is available for operational exploitation onboard Kalvari-class submarine , the Ministry of Defence/Indian Navy have options open to procure AIP system from an international supplier. “While the preference will be given to the indigenously made AIP, keeping the submarine performance issues in mind in the face of the hostile situation in the waters, options are always open to buy urgently from vendors who meet all parameters,” said a top source.

Six Kalvari class (Scorpene) diesel-electric attack submarines (SSKs) under Project 75 are being built by Mazagon Dock Limited (MDL) with the support and technology transfer (ToT) from French company Naval Group (former DCNS). As has been reported earlier, two out of six submarines have been commissioned.

What is the function of AIP ?

“An Air-independent Propulsion (AIP) system onboard a submarine allows conventionally powered submarine to operate without access to the outside air. A Kalvari Class submarine when fitted with an AIP system onboard shall be able to run its electric propulsion motor and electrical network while bypassing the conventional batteries. This shall allow it to remain submerged for a longer duration by reducing the need to surface often to take in the air for running diesel engines for charging conventional batteries” explains Milind Kulshreshtha, a C4I expert.

Though the Kalvari class submarines are powered by conventional diesel-electric propulsion systems, as per the original plans, the last two submarines were to be equipped with an indigenously developed AIP technology. This state of the art Fuel-cell based AIP design was taken up by the DRDO for indigenous development since such technology from abroad was extremely expensive. The fuel cell-based AIP uses hydrogen and oxygen to generate electricity has almost no moving parts (making them quieter) and produces minimal waste.

The indigenous AIP system is still at a developmental stage whilst pending four Submarines under the project are scheduled for commissioning in the next two years. The Made in India AIP system is therefore already planned to be retrofit onboard first submarine which enters a major refit.

Tests & Trials of Indigenous AIP System

It has to undergo a well-defined stringent Testing & Trial stage prior to being qualified even for installation onboard (an operational ship or submarine). According to Kulshreshtha, “A system like AIP shall initially be undergoing multiple Land Based Test Site (LBTS) trials to prove its efficacy ashore. This ashore system version shall be re-designed for fitment onboard a Kalvari class submarine and subsequently installed for experimental trials. The risk here with an R&D version system fitted on an operational vessel is that it may keep going for sea trials as part of multiple iterative improvement cycles, leading to a very undesirable operational situation.”

Indian Navy shall be always eager to enhance the submarine’s operational capabilities (especially in hostile waters) for an active role like intelligence gathering etc. but stuck with an experimental system. Further, it is all too well known that getting an operational vessel tied down ashore for experimental work (as a priority over and above its Operational commitments) is not easy.

Once the R&D version fitted onboard achieves all the desired parameters as per laid down Naval requirements (like noise signatures, efficiency etc.), a ‘production’ version design of indigenous AIP will evolve.

“Then the design shall be handed over to a manufacturing partner (like a Defence PSU) under a ToT for further supply to the Indian Navy. The local Industrial agency shall setup an AIP production division and the first of the system manufactured shall undergo a rigorous Director General Quality Assurance (DGQA) Test Schedule. This procedure includes specialised tests like Type Testing and Environmental Tests. A Type Test procedure establishes the suitability of the manufactured system for Defence application,” the expert adds.

Environmental Checks for Indigenous AIP

As per DGQA procedure, the first AIP system shall undergo Environmental checks like Vibration Test, High Temperature, Damp test, Drip Proof and Tropical test as laid down in the Joint Services Standard (JSS) 55555. While being verified against the laid down Environmental specs, the system usually gets ‘Yellow Banded’ i.e. earmarked as ‘not fit’ for use onboard and kept in the workshop as a reference set.

Installation & Commissioning of AIP

Installation on board a submarine is an involved activity and follows some tough guidelines. The supplier has to provide System Specialists to assist in supervising the work and inspection of work throughout onboard fitment including Connectorisation, Setting to Work, Harbour and Sea Trials. T

Explaining the process, Kulshreshtha adds, “Board of officers from Naval Headquarters, submarine, and Dockyard with assistance from OEM, Shipyard or other suitable agencies shall be constituted for the promulgation of Feasibility of fitment document. This will be further approved by the HQtrs so as to ensure a smooth retro fitment of AIP system. Final acceptance of the system shall be the responsibility of a designated Naval Trial & Testing team for handing over of a completely proven system to the Submarine staff for exploitation and maintenance onboard.”

Operational air-independent propulsion for Kalvari submarines: A critical technology for underwater stealth
 

RISING SUN

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Dec 3, 2017
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HDW will be done by 2030.By 2030 you will have around 5-6 kilos left on their last legs and obsolete.
I advocate either enhanced scorpene if we want cost cut and commonality or type 216 if we want capability.Either will do.
Barracuda is too costly and still not as good as type 216 for shallow waters of arabian sea and bay of bengal.
The budget allocated is around 1.1 billion per boat,you cant get barracuda for that.
Bay of Bengal is deep. Arabian Sea is shallow. I have read reports which clearly states, once submarine leaves the bay from Visakhapatnam, within few miles there is deep sea.
 

Gautam

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Is there any new torpedo procurement for the Kalvari class on the horizon or are we going to continue using the old SUT torpedoes?
Conversations on with Naval Group for the F-21 HWT. They were offering to work with DRDO to modify the torpedo to our needs along with making the thing in India, this is of course if they get a order to make the F-21 the entire submarine fleet standard like the ASRAAM for IAF. I know nothing more at the moment.
 

Aniruddha

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Oct 3, 2019
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Conversations on with Naval Group for the F-21 HWT. They were offering to work with DRDO to modify the torpedo to our needs along with making the thing in India, this is of course if they get a order to make the F-21 the entire submarine fleet standard like the ASRAAM for IAF. I know nothing more at the moment.
Varunastra in its submarine launched form seems to be a good option. Only thing is that the current range of 40kms needs to be increased to 50kms.
 

Gautam

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Indian Navy Scorpene submarines to get DRDO’s “air-independent propulsion” from 2024

By Ajai Shukla, 3rd Dec 19
1575485847525.png

But six new subs being built under Project 75-I will have imported AIP.

The state-of-the-art “air independent propulsion” (AIP) system that the Defence R&D Organisation (DRDO) is indigenously developing will be ready to drive the Indian Navy’s submarines from 2024 onwards.

Consequently, this AIP will not power the six new submarines that the navy is tendering in a Rs 45,000 crore programme called Project 75-I. Instead, those six boats (as the navy traditionally refers to submarines) will have AIP systems that the foreign vendor must offer.

A Request for Information (RFI), which the navy sent out to global vendors under Project 75-I, kept alive both options – an indigenous AIP, as well as a foreign one. Now, top navy sources confirm, a decision has been taken for an imported AIP.

Meanwhile, the DRDO’s AIP system will, from 2024-25 onward, be “retrofitted” into six Scorpene submarines that are currently being built in India under Project 75, say the sources.

The first Scorpene submarine, INS Kalvari, which was commissioned two years ago, is scheduled to undergo its first “mid-life refit” in 2024-25. In this expensive and time-consuming process, the submarine is cut open and each part inspected and, if needed, replaced. During this process, a DRDO-designed AIP will replace Kalvari’s current diesel-electric propulsion system.

The second Project 75 boat, INS Khanderi, was commissioned in September and another four are still to be delivered by Mazagon Dock Ltd, Mumbai (MDL). All these will be retrofitted with DRDO AIP systems as they follow the Kalvari into mid-life refit at two-year intervals.

Ideally, a submarine should undergo a mid-life refit only after sailing for 12-15 years. But with MDL running six years late in Project 75, the Scorpene boats will go in for mid-life refit after sailing for just about eight years.

The bright side of that, say navy sources, is that the Scorpenes will provide a ready platform for the indigenous AIP.

AIP System :

An AIP system powers a submarine without using air from the atmosphere, which is essentially for conventional diesel-electric submarines. In the latter, large banks of electric batteries power electic motors that turn the submarine’s propellers. But the batteries quickly get discharged and the boat must surface every day or two to run onboard diesel generators (which require atmospheric air) to recharge their batteries. During this process, the surfaced submarine is vulnerable to detection since enemy radars quickly detect submarine masts or snorkels protruding above the surface.

To avoid detection, the ideal solution is nuclear propulsion. Nuclear reactors require no oxygen, which allows these submarines almost indefinite underwater endurance. However, nuclear propulsion has technology challenges and India is struggling to build a reactor small enough for an attack submarine.

AIP provides the next best solution, allowing submarines to remain underwater for up to two weeks, which provides the enemy with less opportunity to detect a surfaced boat.

The most common AIP systems use “fuel cell technology”, which generates power through the reverse electrolysis of oxygen and hydrogen, with the two elements chemically combining to generate electricity to charge the submarine’s batteries. However it is dangerous to store highly inflammable hydrogen on board.

The DRDO’s AIP system relies on the innovative Phosphoric Acid Fuel Cell (PAFC) technology. This is more rugged, tolerant of fuel impurities, and offers longer life and efficiency, which makes it cost-effective.

A month ago, navy chief, Admiral Karambir Singh, visited the Naval Materials Research Laboratory (NMRL) at Ambernath, Maharashtra – the DRDO laboratory that is developing the indigenous AIP – to witness progress. Navy officers say he was demonstrated a land-based prototype (LBP) of the AIP, which has demonstrated the ability to generate power, independent of air, for up to two weeks.

The DRDO’s current challenge is to develop this LBP into a “marinised” AIP system, which can fit into an actual submarine and operate underwater in live conditions. Navy and DRDO sources are confident that can be achieved in three-to-four years.

The navy had the option to fit French AIP systems into the Scorpene submarines that were contracted in 2005 under Project 75. However, the French offered a relatively untried system called “Module d'Energie Sous-Marine Autonome (MESMA). The navy decided not to take the risk and ordered a conventional diesel-electric system instead, with the DRDO charged with developing an indigenous AIP.

Pakistan’s navy ordered the MESMA AIP system for its Agusta 90B submarines. There have reportedly been problems with its reliability and effectiveness.

Broadsword: Indian Navy Scorpene submarines to get DRDO’s “air-independent propulsion” from 2024
 

Gautam

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Navy to get third Scorpene submarine in December

By Dinakar Peri
LUCKNOW, February 06, 2020 04:02 IST


The third Scorpene submarine, Karanj, will be delivered to the Indian Navy by December and all six submarine deliveries would be completed by 2022, Nicolas de La Villemarque, Vice President India, Asia and Pacific of Naval Group, said on Wednesday.

Mr. Villemarque said discussions were on to fit Air Independent Propulsion (AIP) modules on all Scorpenes beginning 2023. “The Scorpene submarine has the ability to be equipped with an AIP system. The first AIP will be equipped during the first refit of the first Scorpene,” he said in a conversation with The Hindu at Defexpo 2020, which began here on Wednesday.


Talks were underway with the Defence Research and Development Organisation (DRDO), Mazagon Dock Shipbuilders Limited (MDL) and the Navy. A design agreement was expected to be signed with the DRDO by the year end, he stated.

Karanj was launched into water in January 2018 and is currently in advanced stages of sea trials. The first Scorpene, Kulvari, was commissioned in 2018 and it would go for a normal refit after six years in 2023, during which time time the AIP would be installed. Second Scorpene Khanderi was inducted in September last.

An indigenous fuel cell-based AIP module is currently under development by the DRDO. The project reached a milestone in October 2019 with the successful operation of a land-based prototype engineered to the form-and-fit of a submarine. The DRDO has expressed confidence that the module will be ready in time for installation on Kulvari.

An AIP module gives stealth and extended endurance to diesel-electric submarines by allowing them to stay submerged longer.

Mr. Villemarque said they would do design simulations to “work out the technicalities of the project which involves Jumboisation, the process of cutting, joining and putting various blocks together.”

Project-75I

Naval Group is among the five Original Equipment Manufactures (OEM) shortlisted for the Navy’s project for advanced submarines under Project-75I being processed through the Strategic Partnership (SP) model of defence procurement. MDL and Larsen & Tourbo are the two Indian companies shortlisted under it and the Request For Proposal (RFP) would be issued to them.

Mr. Villemarque said they awaited a interest from the Indian companies to discuss potential tie-ups. “Our submarine is bespoked to the Indian Navy requirements. It was based in both Scorpene and Barracudda class platforms,” he added.

The Naval Group last month responded to the Navy’s long-pending tender for heavy weight torpedoes, which would equip the Scorpenes.

Delayed plan

Earlier, the Navy planned to install AIP modules on the last two of the six Scorpenes as they rolled out of the production line. However, it could not be realised due to developmental delays.

MDL is manufacturing the submarines with technology assistance from the Naval Group under a $3.75 bn deal signed in October 2005.

https://www.thehindu.com/news/natio...in-december/article30744577.ece?homepage=true
 
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Ankit Kumar

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Same things will happen in 75-- I

Better buy more KILO class for numbers

A lot of time , money and efforts have gone here. And now the production and delivery are becoming stable. Not wise to buy another kind of submarine now.

Apart from obvious advantages in weapons, service rates, operational safety , ordering more Scorpenese will keep our MDL SSK production line running.

Else it will be Type209 story all over again.
 
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Bon Plan

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Same things will happen in 75-- I

Better buy more KILO class for numbers
And what about the make in India?
If you want to produce Kilo (a good product) in India, it will takes time. Some years...
On the other hand Scorpene is there, efficient, modern, with a mature production line. The choice seems easy.

But in India things never happen in a full logic mode :eek: