DRDO Develops Air Independent Propulsion Technology for Indian Submarines

India’s Defence Research and Development Organization (DRDO) said it completed the final development test of Air Independent Propulsion (AIP) that allows diesel electric submarines to remain underwater for longer periods besides making them “quieter,” on Monday night.

“DRDO has achieved an important milestone in the development of AIP System by proving the land based prototype on 8 March 2021. The plant was operated in endurance mode and max power mode as per the user requirements,” the company announced.

The system is being developed by Naval Materials Research Laboratory (NMRL) of DRDO. The technology has been successfully developed with the support of industry partners L&T and Thermax.

AIP enhances the submerged endurance of the boat. Fuel cell-based AIP has merits in performance compared to other technologies. While there are different types of AIP systems being pursued internationally, fuel cell based AIP of NMRL is unique as the hydrogen is generated onboard.

It has now reached the stage of maturity for fitment into target vessels. The Indian Navy can now retrofit all of its Kalvari-class submarines with AIP during their first upgrade, expected around 2023.