The Project 17A Frigate programme is a major indigenous defence acquisition scheme of the Indian Navy to construct a series of advanced stealth guided-missile frigates, officially designated as the Nilgiri-class. The programme was approved by the Cabinet Committee on Security (CCS) in February 2015 with an estimated total cost of approximately ₹45,000 crore. It is a follow-on series to the three Project 17 (Shivalik-class) frigates, incorporating improved stealth features, advanced weapons, and sensors.
The project's primary mechanism involves the construction of seven frigates split between two public sector shipyards: Mazagon Dock Shipbuilders Limited (MDL) in Mumbai, which is building four ships, and Garden Reach Shipbuilders and Engineers (GRSE) in Kolkata, which is building the remaining three. The ships are designed in-house by the Indian Navy's Warship Design Bureau (WDB) and are the first major class of Indian-designed warships to use the Integrated Modular Construction methodology. This technique involves pre-outfitting large hull blocks before final assembly, which significantly reduces the overall construction time. The frigates, named after Indian hill ranges like INS Nilgiri and INS Mahendragiri, are multi-mission platforms with a displacement of approximately 6,670 tonnes and a length of 149 meters.
The frigates are equipped with advanced systems, including the Barak-8 surface-to-air missiles and BrahMos supersonic cruise missiles, and are the first Indian Navy frigates to deploy Vertical Launching System (VLS) cells for their surface-to-air missiles, a key difference from the predecessor Project 17. The programme is a crucial component of the Aatmanirbhar Bharat initiative in the defence sector, with the ships featuring approximately 75% indigenous content. The project connects to the broader goal of enhancing the Indian Navy's blue-water capability and ensuring maritime security in the Indian Ocean Region (IOR). The most recent development is the commissioning of ships like INS Mahendragiri in February 2026 and the delivery of INS Dunagiri on March 31. The programme is set to be succeeded by the more advanced Project 17 Bravo, which is currently in the Request for Proposal (RFP) stage.