•The P-75I, it intends to design and build conventional submarines indigenously.
•An air independent propulsion (AIP) module developed by DRDO is now awaiting fitment on the Scorpene-class submarines.
•The first Scorpene-class submarine Kalvari is expected to go for refit in 2025.
•An AIP module acts as a force multiplier as it enables conventional submarines to remain submerged for a longer duration thereby increasing their endurance and reducing chances of detection.
•The DRDO-developed AIP module is phosphoric acid-based which is widely available, officials noted.
•An AIP module has a stack of fuel cells generating hydrogen.