Sixth Nilgiri-class frigate joins fleet, boosting naval firepower

INS Mahendragiri, the sixth ship of the Nilgiri-class (Project 17A) advanced stealth guided-missile frigate programme, was delivered to the Indian Navy at Mu...

What Happened

INS Mahendragiri, the sixth ship of the Nilgiri-class (Project 17A) advanced stealth guided-missile frigate programme, was delivered to the Indian Navy at Mumbai on May 1, 2026.
The delivery occurred at Mazagon Dock Shipbuilders Limited (MDL), which built and handed over the vessel.
INS Mahendragiri is the sixth Project 17A ship delivered within less than 17 months of the first ship in the series, INS Nilgiri, which was delivered in December 2024.
The frigate is equipped with an advanced sensor suite and a comprehensive weapons package capable of anti-surface, anti-air, and anti-submarine warfare (ASuW, AAW, and ASW).
The vessel was designed by the Warship Design Bureau (WDB) and overseen by the Warship Overseeing Team in Mumbai, exemplifying India's indigenous warship design and construction capability.

Static Topic Bridges

Project 17A (Nilgiri-Class Frigates) and Indigenisation

Project 17A is a programme to build seven advanced stealth guided-missile frigates for the Indian Navy at a total cost of approximately ₹45,000 crore, sanctioned by the Defence Acquisition Council. The ships are built at two public sector shipyards — Mazagon Dock Shipbuilders Limited (MDL) in Mumbai and Garden Reach Shipbuilders & Engineers (GRSE) in Kolkata. Approximately 75% of the components are indigenously sourced, making it a landmark programme under India's "Aatmanirbhar Bharat" defence manufacturing initiative.

Project 17A frigates are successors to the Shivalik-class (Project 17) frigates and are larger, stealthier, and more capable
Displacement: 6,670 tonnes; Length: 149 metres; Maximum speed: ~32 knots; Range: 5,500 nautical miles
Crew: 226 personnel (35 officers, 191 sailors)
Propulsion: CODAG (Combined Diesel and Gas) system — two LM2500 gas turbines and two MAN diesel engines

Connection to this news: INS Mahendragiri is the sixth in this seven-ship series, with delivery within 17 months of the first ship, demonstrating the accelerating pace of indigenous warship construction in India.

Multi-Domain Naval Warfare Capabilities

Modern frigates are designed to operate across three warfare domains simultaneously. Anti-Surface Warfare (ASuW) targets enemy surface ships; Anti-Air Warfare (AAW) defends against aerial threats including missiles and aircraft; Anti-Submarine Warfare (ASW) detects and neutralises submarines. The Nilgiri-class integrates advanced systems for all three domains into a single hull.

ASuW: 8 × BrahMos supersonic cruise missiles (Mach 2.8–3), VLS-launched
AAW: 32 × Barak-8 Long-Range Surface-to-Air Missiles (LR-SAM); AK-630 CIWS for close-in defence
ASW: BEL HUMSA-NG hull-mounted active/passive sonar; Shyena lightweight torpedoes; RBU-6000 rocket launchers
Combat Management: CMS-17A system with inter-platform data links
Electronic Warfare: DRDO-developed Shakti EW suite with ESM/ECM capabilities and Radar Finger Printing System (RFPS)

Connection to this news: INS Mahendragiri's induction directly expands the Indian Navy's capacity for multi-domain blue-water operations in the Indian Ocean Region — a strategically critical zone given increased maritime competition.

Naval Stealth Technology

Stealth in modern warships refers to reducing the vessel's detectability across multiple signatures — radar, infrared, acoustic, and magnetic. The Nilgiri-class incorporates a comprehensive stealth package developed and customised for Indian conditions.

Radar Cross-Section (RCS) reduction: composite materials, radar-absorbent coatings, flush deck-mounted weapon systems, and minimised antenna count
Infrared (IR) signature reduction: Venturi effect exhaust cooling and fluid injection to reduce exhaust plume temperatures
Acoustic signature reduction: specially designed low-cavitation propellers and hull acoustic enclosures for machinery
Magnetic signature reduction: degaussing systems

Connection to this news: The Nilgiri-class represents the most capable stealth surface combatant India has designed and built domestically, and INS Mahendragiri's induction adds this stealth and combat capability to the operational fleet.

Warship Design Bureau (WDB) and India's Defence Ecosystem

The Warship Design Bureau, an in-house design organisation of the Indian Navy, is responsible for design of naval vessels. Operating under the Integrated Headquarters of Ministry of Defence (Navy), WDB has designed a succession of progressively more capable warships, enabling India to reduce dependence on foreign ship designs.

WDB has designed all classes of major Indian warships since the INS Nilgiri (original, 1972)
Project 17A is one of the most technically complex designs by WDB
Defence shipyards MDL and GRSE are the primary builders under DPSUs (Defence Public Sector Undertakings)

Connection to this news: The delivery of INS Mahendragiri is the outcome of WDB's design and MDL's construction, validating India's end-to-end indigenous capability in advanced warship design and building.

Key Facts & Data

Project 17A total programme cost: approximately ₹45,000 crore (7 ships)
Seven ships in class: Nilgiri (F33), Himgiri (F34), Udaygiri (F35), Taragiri (F41), Dunagiri (F36), Vindhyagiri (F42), Mahendragiri (F38)
INS Nilgiri (first ship) delivered: December 20, 2024; INS Mahendragiri (sixth) delivered: May 1, 2026
All six delivered within 17 months — faster than comparable programmes globally
Displacement: 6,670 tonnes; indigenous content: ~75%
Built at: MDL (Mumbai) and GRSE (Kolkata)
BrahMos missile: Mach 2.8–3 speed, range up to 450 km (extended range variant)
MFSTAR radar (EL/M-2248): Active Electronically Scanned Array (AESA), 450+ km detection range
The seventh and final Project 17A ship is yet to be delivered