Project 75I

– By Alan Jai Kuriako & Sunith S Mani

Initial Scope of Project 75I

The Project 75I is a new generation submarine acquisition plan of the Indian Navy in order to build 6 more submarines as a technological successor of the previous Kalvari Class (Project 75). The new project aims for two objectives. The first objective is for a second assembly line to be created for SSK submarines other than the Mazagon Docks (MDL) – which is currently building the Kalvari Class, so that there is no delay in the supply of submarines to the Indian navy, which is at an all-time low fleet level. The second is to build a new type of submarine with more enhanced features, with the Navy hoping that the lessons from these two SSK projects will be fused together while formulating the design for the indigenous SSK of the future (Project 76).

The contenders currently include; SMX 3.0 (final design unsure as of now – Naval Group), Amur 1650 (Rubin Design Bureau), S80 (Navantia), HDW Type 214 (TKMS), KSS-III (Daewoo). Saab’s A26 offer was removed due to the frustrations that the company had faced with the procurement policy of the government. TKMS is also looking at a possibility of not offering its submarine as well due to similar policies.

The policy involved is actually the biggest issue of this entire deal. For a reasonably small quantity of submarines (6 x units), there are numerous issues that the potential winner will face. Firstly, at a 51% ownership for the local vendor removes any control for the foreign firm in a joint venture. This means that the government will still blame the foreign entity for any malfunctions faced by the project (similar to what killed the first Rafale deal of the UPA era). This can be extremely hard for a foreign entity, especially in this particular deal where the testing is done purely in theory (some of the vendors don’t even have the production prototype that meets the requirements of the Indian Navy – such as the VLS module). In this case, the risk factor for foreign vendors are extremely high.

New capabilities that might be of interest to the Indian Navy includes;

  • More advanced AIP system
  • VLS module for missiles (they could include; Brahmos, LRLACM, Rudra Series)
  • Drone launch system (for AUV)
  • Camera Mast instead of traditional periscopes that allow the commander to have situational awareness anywhere on the ship
  • Enhanced stealth features (shrouded propellers – pump jet)

Most of these capabilities do not honestly require a completely new platform but could be added into existing platforms since modern submarines have a modular design profile. Russia also has already hinted that they are not interested in helping India to integrate the Brahmos family of weapons into any foreign submarine design. Therefore, India’s reasonable choice is to either purchase the Amur Class or the more optimum choice of building on the Scorpene submarine platform, either by enlarging the existing design available to India or by adopting the newer SMX 3.0 as part of a natural upgradation of the design language.

Revamping the Kalvari for P75I and P76

For Project 75I, there are many benefits of adopting the Kalvari as the base platform. Modernising the design while replacing a number of systems as well as the software with Indian alternatives help keep the design synonymous with the original P75 submarines and therefore make it easier for sailors to transition, instead of a completely unfamiliar design that would make training costlier as different training systems need to be purchased.

Project P75I
Source : Alpha-Defense

Currently, the DRDO AIP system is planned for the Kalvari class submarines. Submarines which boasts of advanced air-independent propulsion systems (AIP) can submerge for a longer periods of time. This will also potentially increase the operational range of these submarines. The MESMA system was originally offered by the French shipyard (DCNS) for the Kalvari Class. It is a closed-cycled steam turbine system that is essentially a modified version of their nuclear propulsion system with heat generated by ethanol and oxygen.

Although MESMA can provide higher output power than the other alternatives, its inherent efficiency is the lowest of the four AIP candidates, and its rate of oxygen consumption is correspondingly higher (Undersea Warfare Magazine). The DRDO AIP on the other hand is a fuel cell based system which is the latest generation of AIP systems.

The Kalvari has a modular architecture system which means that the length of the vessel can be extended by adding different mission modules. The DRDO AIP is one such module that is going to be added during the mid-life refit of the existing Kalvari fleet. By designing an Indian VLS module for the modernised Kalvari design for the future P75I and P76, there are numerous benefits that can be attained. This include the ability to retrofit any indigenous/foreign missile as well as the ability to add the same module to the existing Kalvari submarines to augment it further.

Drone launch systems can also be added to the existing Kalvari submarine as well as to the future projects as well. For example, L&T had already built a collection of autonomous underwater vehicles (Maya, Amogh and Adamya). These can already be tube launched from existing submarine torpedo tubes, but a recovery system still need to be retrofitted (like the drone recovery system on the SMX 3.0 SSK). These AUVs allow the submarine to standby offshore, while it takes recon operations of the coast or at a port of interest. 

Another retrofittable next generation technology that can be added into the entire SSK line-up is a digital optronic mast. The benefit of this system is that as compared to traditional periscopes, it allows the commander to have complete situational awareness wherever he is on the ship, without the need to be in the command centre. There is already an indigenous mast built by Tonbo Imaging by the name of Varuna. Varuna features a multi spectral, multi aperture constant staring array of visible light and advanced thermal cameras. An interesting feature of this mast is that it can generate a full-panoramic view in just 2 secs including the mast exposure time. This allows the submarine to get a good view of the surface within the shortest amount of time, thus limiting its exposure to enemy vessels.

These retrofittable systems will make the entire Project 75, 75I and 76 more homogenous in nature. Additional features (such as pump jet propulsion) can be added to these submarines in a phased manner that will make the project groups slightly distinct from each other. A continuous relationship with an innovative firm such as DCNS ensures that India will continue to get upgradable next generation technology that will cement its position as the premier submarine power in the Indian Ocean Region.

By Alpha Defense

Alpha Defense initially a solo venture but now a defense group by people from various demographics of India covering defense news and updates. We believe in unbiased analysis of every subject in hand. Our mission is to provide simplfiied defense information to the public.

One thought on “Project 75I”
  1. This saga will take another 10 years. In our country govt take defence needs as 10 -15 year plan to fulfil. This tender was first announced back in 2007 and still nothing is done. We made scorpene submarine in similar fasion but how much tech did we able to obsourb really. I strongly feel making more scorpene submarines like super scorpene is the only way forward if we are really serious about being indepedent in terms of submarime building. China is incresing its submarine numbers in rapid pace to time to act fast. P75i will take rime atleast 5 years after the contract signing so we have to continue making more scorpenes and try to obsorb as much as we can. PSU acxoutability is also very important otherwise all these efforts will be off no use.

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