A file picture of 'INS Karanj' during its launch in Mumbai.

Discussions on to install AIP modules on Scorpenes from 2023

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.”


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.