Prime Minister Shri Narendra Modi commissions three indigenously designed and built naval ships – INS Dunagiri, INS Sanshodhak and INS Agray at Syama Prasad Mookerjee Port, Kolkata, West Bengal

I now have sufficient Tier 1 facts. Writing the study note.


Study Note: Commissioning of INS Dunagiri, INS Sanshodhak & INS Agray (21 June 2026)


1. At a Glance


2. Why in the News


3. Background & Evolution

Indian Naval indigenisation trajectory: - Post-1965 war, India began building warships domestically; GRSE (est. 1884, under MoD) emerged as a premier warship builder. - 1999–2000: Defence Procurement Procedure (DPP) laid the foundation for categorised indigenous procurement. - 2015: Make in India in defence announced; indigenisation targets set for ordnance, platforms, electronics. - 2020: Aatmanirbhar Bharat defence reforms — positive indigenisation lists published; GRSE designated key shipyard. - Warship Design Bureau (WDB) — formerly Directorate of Naval Design — entrusted with in-house design of all three vessels.

Project milestones:

Year Milestone
2015 Project 17A (Nilgiri class frigates) contract signed with MDL & GRSE
2019 First P17A ship Nilgiri launched at MDL
Jul 2022 Dunagiri (Y-3023) launched by Raksha Mantri at GRSE [S6]
Jun 2023 Sanshodhak (4th SVL) launched at L&T Kattupalli, Chennai [S7]
Mar 2024 Agray and Akshay (5th & 6th ASW SWC) launched at GRSE [S8]
Jan 2024 INS Sandhayak (1st SVL) commissioned at Visakhapatnam [S9]
Mar 2026 Dunagiri delivered to Indian Navy at GRSE
21 Jun 2026 INS Dunagiri, INS Sanshodhak, INS Agray commissioned by PM Modi, Kolkata [S1]

4. Core Static Facts

INS Dunagiri

Parameter Detail
Class Nilgiri Class (Project 17A)
Yard No. Y-3023
Type Advanced Stealth Guided Missile Frigate
Position in class 5th of 7 Project 17A ships; 2nd built at GRSE
Builder GRSE, Kolkata
Displacement ~6,700 tonnes
Predecessor class Shivalik Class (Project 17)
Propulsion CODOG (Combined Diesel Or Gas) — Diesel Engine + Gas Turbine; Controllable Pitch Propeller (CPP)
Features Reduced radar cross-section; advanced stealth shaping; Integrated Construction philosophy
Indigenous content >75%
Delivery to Navy 30 March 2026

INS Sanshodhak

Parameter Detail
Class Survey Vessel Large (SVL)
Position in class 4th of 4 SVL ships
Builder L&T (Kattupalli) / GRSE, Kolkata
Displacement 3,400 tonnes
Length / Beam 110 m / 16 m
Mission Full-scale coastal & deep-water hydrographic survey; oceanographic & geophysical data collection
Applications Navigation chart updates, port/harbour approach surveys, defence & civil use
Indigenous content >80% by cost
Launch 13 June 2023, Kattupalli, Chennai

INS Agray

Parameter Detail
Class Arnala Class
Type Anti-Submarine Warfare Shallow Water Craft (ASW SWC)
Project 8 × ASW SWC project (GRSE)
Position in class 4th ship delivered by GRSE; launched as 5th of the project
Builder GRSE, Kolkata
Length ~77 m
Weapons & Sensors Lightweight Torpedoes; Indigenous Rocket Launchers; Shallow-water SONAR
Mission ASW in coastal waters; Low Intensity Maritime Operations (LIMO); Mine Laying
Launch 13 March 2024, GRSE, Kolkata

Common Facts


5. Multi-Dimensional Analysis

Strategic / Geopolitical

Scientific / Technological

Economic / Industrial

Environmental / Hydrographic

Administrative / Governance


6. Recent Developments (Last 12–18 Months)


7. Prelims Hooks

  1. INS Dunagiri belongs to Nilgiri Class, which is the Project 17A family of stealth frigates — not Project 17 (Shivalik Class). [S3]
  2. INS Dunagiri is the 5th ship of Project 17A and the 2nd P17A ship built at GRSE (the other P17A ships are built at MDL, Mumbai). [S3]
  3. All three ships were designed by the Warship Design Bureau (WDB) of the Indian Navy — not DRDO, not GRSE's own design wing. [S1]
  4. INS Sanshodhak is the 4th and final ship of the Survey Vessel Large (SVL) programme; the 1st SVL was INS Sandhayak, commissioned in January 2024. [S7][S9]
  5. INS Agray belongs to the Arnala Class of Anti-Submarine Warfare Shallow Water Crafts — designed for coastal ASW, LIMO, and mine-laying. [S8]
  6. All three platforms commissioned at Syama Prasad Mookerjee Port, Kolkata — formerly known as Kolkata Port Trust. [S1]
  7. The commissioning date 21 June also marks World Hydrography Day — specifically noted by PM Modi in relation to INS Sanshodhak. [S1]
  8. Indigenous content: >75% for all three vessels; INS Sanshodhak specifically exceeds 80% by cost. [S1][S7]
  9. Over 200 MSMEs participated in the construction of these three ships. [S1]
  10. INS Dunagiri uses CODOG (Combined Diesel Or Gas) propulsion with Controllable Pitch Propellers (CPP). [S3]
  11. INS Agray is approximately 77 metres in length; INS Sanshodhak is 110 metres long with a displacement of 3,400 tonnes. [S8][S7]
  12. The Arnala class ASW SWC programme comprises 8 ships total, all being built by GRSE, Kolkata. [S8]
  13. Project 17A frigates displace approximately 6,670–6,700 tonnes — about 5% larger than the predecessor Shivalik class. [S3]
  14. INS Agray is equipped with Lightweight Torpedoes, Indigenous Rocket Launchers, and shallow-water SONAR. [S8]
  15. GRSE (Garden Reach Shipbuilders & Engineers) is a Miniratna Category-I Defence Public Sector Undertaking under the Ministry of Defence. [S2]

8. Mains Relevance

GS Papers: - GS-II: Government policies and interventions for development in various sectors; India's defence procurement policy; bilateral/multilateral strategic relations. - GS-III: Defence indigenisation; Indian economy and industry; science and technology — achievements of Indians in science & technology; awareness in the fields of IT, space, computers, robotics, nano-technology, bio-technology.

Specific Syllabus Headings: - Indigenisation of defence production; Aatmanirbhar Bharat in defence. - Security challenges and their management in border areas; role of external state and non-state actors in creating challenges. - Achievement of Indians in science & technology; indigenisation of technology and developing new technology.

Plausible Mains Question Stems:

  1. "The simultaneous commissioning of INS Dunagiri, INS Sanshodhak and INS Agray marks a qualitative shift in India's naval self-reliance. Analyse the strategic and economic significance of indigenous warship construction for India's national security architecture." (GS-III / 250 words)

  2. "Hydrographic survey vessels are as critical to national security as combat platforms. Evaluate this statement in the context of India's Survey Vessel Large (SVL) programme." (GS-III / 150 words)

  3. "India's defence indigenisation journey has been incremental rather than transformative. Critically examine, with reference to the shipbuilding sector." (GS-II/III / 250 words)


9. Related Topics to Study Next

Topic Connection
Project 17A (Nilgiri Class) Full Programme INS Dunagiri is the 5th of 7 ships; understanding the full programme is essential for tracking India's surface combatant fleet build-up.
Mazagon Dock Shipbuilders (MDL) Co-builder of Project 17A ships; paired with GRSE for the full 7-ship order — often confused with GRSE in exams.
Defence Acquisition Procedure (DAP) 2020 Policy framework governing all three ships' procurement; Buy (Indian-IDDM) category definitions are directly testable.
Positive Indigenisation Lists (PIL I, II, III) Components of these ships fall under PILs; critical for understanding Aatmanirbhar Bharat in defence.
Indian Ocean Region (IOR) Security Geopolitical theatre where these ships will operate; connects to China's String of Pearls, QUAD, SAGAR doctrine.
World Hydrography Day & IHO Directly referenced in PM's commissioning speech; IHO membership, India's hydrographic obligations, NCOG.
Arnala Class ASW SWC Programme The 8-ship programme of which INS Agray is a part; GRSE's largest warship contract by number of hulls.
GRSE & DPSUs in Defence GRSE, MDL, BEL, HAL — their roles, Miniratna/Navratna status, and privatisation debate are recurring Prelims themes.

10. Common Errors / Trap Areas

  1. Confusing INS Dunagiri's class name with its predecessor: INS Dunagiri is Nilgiri Class (P17A) — not Shivalik Class (P17). A previous INS Dunagiri existed (Leander-class frigate, decommissioned 2010); the current one is the name reused.

  2. Wrong builder for INS Sanshodhak: It was launched at L&T's Kattupalli shipyard (Chennai) but delivered and commissioned through GRSE, Kolkata. Aspirants often write L&T as the sole builder or GRSE alone — the correct answer is L&T/GRSE collaborative construction. [S7]

  3. Mixing up SVL ships: INS Sandhayak = 1st SVL (commissioned Jan 2024 at Vizag); INS Sanshodhak = 4th and last SVL (commissioned Jun 2026 at Kolkata). Do not confuse the two — both names begin with 'S'.

  4. Wrong port name: The commissioning occurred at Syama Prasad Mookerjee Port — not "Kolkata Port" or "Haldia Port." The port was renamed in 2021 from Kolkata Port Trust; UPSC has tested renamed institutions.

  5. Overstating Agray's position in its class: PIB sources alternately describe INS Agray as the "4th ship delivered by GRSE" and the "5th ship of the 8-ship project." The resolution: it is the 5th hull in the overall Arnala class order but the 4th delivered by GRSE. Do not assert it is the 4th ship of the class unconditionally.


11. Sources