India’s indigenous Air Independent Propulsion (AIP) system for diesel-electric submarines has achieved a significant milestone with the inauguration of the Setting to Work (STW) Phase-2 activity of its Energy Module at LNT’s AM Naik Heavy Engineering Complex in Hazira, Gujarat, on Saturday.
Developed by the Defence Research and Development Organisation’s (DRDO) Naval Materials Research Laboratory (NMRL), the AIP system is designed to enhance the underwater endurance of the Indian Navy’s conventional submarines by reducing their dependence on atmospheric oxygen.
Defence Secretary, Secretary of the Department of Defence R&D and DRDO Chairman Rajesh Kumar Singh inaugurated the activity virtually. Vice Admiral B Sivakumar, Chief of Materials, Indian Navy, and Dr R Balamuralikrishnan, Director General (Naval Systems & Materials), DRDO, attended the ceremony at Hazira.
Addressing the event, the DRDO Chairman congratulated the DRDO team and industry partners, acknowledging their scientific efforts and industrial collaboration in advancing the indigenous AIP programme. He also recognised the Indian Navy’s support throughout the programme, including its role in testing and validating the system at different stages of trials.
He stressed the need to progress through the subsequent phases in line with the Navy’s planned induction timelines, while maintaining stringent safety standards for hydrogen and fuel-cell technologies.
In the next phase, the AIP Energy Module will be energised for power generation and subjected to rigorous testing in accordance with Indian Navy protocols. Following successful testing, it is scheduled to be handed over to Mazagon Dock Shipbuilders Limited (MDL) for integration with a Kalvari-class submarine in early 2027.
The milestone marks further progress in India’s efforts to develop indigenous submarine technologies and strengthen the operational endurance of its conventional underwater fleet.
