Indian subs will be fitted with AIP made in India: DRDO Chief

In a major boost to Atma Nirbhar Bharat initiative of the government, the Fuel Cell based Air Independent Propulsion (AIP) System of the Defence Research and Development Organisation will soon be ready to be fitted on board INS Kalvari.

In an exclusive conversation with Financial Express Online in New Delhi, Secretary, Department of Defence R&D and Chairman DRDO Dr G Satheesh Reddy said “When the boat comes up for retrofitting in 2025, it will be fitted with the indigenous AIP which has been made in India by DRDO and Indian industry.”

“Work is going on to develop a module which has to be fitted on the submarine when it comes. There are industry partners including Larsen & Toubro and Thermax, and the Naval Materials Research Laboratory (NMRL) of DRDO which has developed this.”

The AIP which is being developed here in India is based on the specifications and requirements shared by the end user – the Indian Navy.

Why is AIP needed?

Financial Express Online has reported earlier that AIP is a critical technology needed for the Kalvari class submarines that will make the diesel electric submarine more lethal by enabling it to stay under water for an extended period of time.

In 2021, in an official statement DRDO has said that the Fuel cell-based AIP has merits in performance as compared to other technologies.

How? Because it uses oxygen and hydrogen which is used for generating electricity and there are no moving parts involved which means it makes the submarine not only quieter than a nuclear submarine but also ensures there is minimal waste. In a nuclear submarine the reactor of the ship which is constantly pumping coolant to maintain temperatures of the engine makes a lot of noise. However, AIP equipped submarines remain silent, making them more deadly by enhancing the submerged endurance several fold.

Also with fuel-cell based AIP it will help in taking advantage of internal refraction in equatorial waters because of the differences in temperatures within the ocean and on the surface.

Plans of the Indian Navy

As has been reported in Financial Express Online all the submarines under Project 75 – Kalvari class will be fitted with AIP when they come up for their first upgrades starting 2025.

Earlier the date for the first boat to come up for upgrade was mentioned by top officials as 2023. Six 1615 tonne submarines have been built

by Mazagon Dockyards Limited (MDL) Mumbai, and in joint collaboration with the French Naval Group based on Scorpene design.

Which other countries have AIP technology in the world?

Germany, South Korea and France. And soon India will join this exclusive group.