INS Kolkata

The keel of Kolkata was laid down in September 2003 and she was launched on 30 March 2006. Her commissioning was originally planned for 2010, but this was delayed to 16 August 2014 as a result of a series of project delays. During her construction at MDL, she was given the designation Yard-701.

Sea trials

The commissioning of Kolkata was delayed from 2010 to 2014 due to delays in her construction and technical problems which were found during her sea trials. The issue detected was the generation of additional noise, which occurred when the engine, gearbox and shaft were operated together, but which worked issue-free when run independently. The issues were fixed and the sea trials were completed by February 2014, when the ship returned to MDL to undergo minor work before delivery.

2014 carbon dioxide leak

On 7 March 2014, during a complete check-up of the ship's machinery to fix the problems found during sea trials, a naval officer was killed and several workers were injured when a valve on a CO₂ bottle malfunctioned during a test of the vessel's carbon dioxide fire-fighting unit at the Mazagaon dockyard. For the test, fire-retarding carbon dioxide gas was to be released into a compartment; the test was part of the destroyer's delivery trials. Kolkata's engineering officer-designate, Commander Kuntal Wadhwa, inhaled a large amount of gas and was rushed to St George's Hospital, where he was pronounced dead. Two dockyard officials who also inhaled the gas were also taken to hospital for treatment. MDL stated that the incident will not delay the scheduled commissioning of the ship.

Weapon trials

As part of her pre-commissioning weapon trials at sea, Kolkata test-fired a BrahMos missile off Karwar's coast on 9 June 2014, and the test met all parameters. On 15 February 2015, a BrahMos missile was test fired from INS Kolkata during the Tropex exercise in the Arabian Sea.

On 29 December 2015 and 30 December 2015 the Indian Navy successfully test-fired the Barak 8 missile from INS Kolkata. Two missiles were fired at high speed targets, during naval exercises being undertaken in the Arabian Sea.

Operation Sankalp: 2023-24 anti-piracy patrols

Against the backdrop of an increase in attacks on commercial ships transiting the Red Sea, the Gulf of Aden, and the Arabian Sea, on 21 December 2023, the Indian Navy increased maritime surveillance efforts in the Central and North Arabian Sea by deploying the P-8I Neptune maritime patrol aircraft and the SeaGuardian drone. The Indian Navy deployed a large flotilla of destroyers to safeguard international security.

On 4 March 2024, INS Kolkata, deployed to the Gulf of Aden, responded to a request from MSC Sky II, a Liberian flagged container vessel, that had reportedly been attacked by a drone or missile, at about 1900 h (IST) on 4 March 24, 90 nm southeast of Aden. The ship's master reported smoke and flames onboard following the attack. INS Kolkata was quickly redirected to provide the required support, and by 2230 hours (IST), it had reached the incident site. The Kolkata then escorted the ship from the area of the incident into the territorial seas of Djibouti at the master's request. Early on 5 March, a 12-person specialised firefighting team from Kolkata boarded the Sky II and extinguished the remaining fires. In addition, an explosive ordnance disposal team boarded the Sky II to evaluate residual risk. The 23-person crew, 13 of whom were citizens of India, were safe, and the ship continued sailing towards its next destination.

On 6 March 2024, INS Kolkata responded to another situation in the Gulf of Aden. About 55 nautical miles southwest of Aden, a drone or missile struck the Barbados-flagged bulk carrier MV True Confidence, igniting a fire and seriously injuring multiple crew members. When INS Kolkata arrived on the site, it used its onboard aircraft and boats to successfully rescue 21 crew members, including one Indian national, from life rafts. The injured crew members received vital medical attention from the ship's medical experts.

According to the US Central Command (CENTCOM), an anti-ship ballistic missile had struck the Barbados-flagged Liberian-owned MV True Confidence. Three people were listed as critically injured, three as fatal, and at least four injuries were reported by the ship's crew. There was significant damage to the ship.

On 17 March 2024, INS Kolkata rescued 17 crew members and captured 35 pirates from the ex-Malta flagged MV Ruen, which had been hijacked on 14 December 2023, after a 40-hour long operation. As an Indian helicopter approached the hijacked ship, the pirates opened fire at it, shot down a ship-based UAV used for monitoring, and attacked the INS Kolkata as it intercepted the hijacked vessel. The interception was carried out about 2,600 km from the Indian coast. INS Kolkata disabled the ship's steering system and navigational aids, forcing the hijacked vessel to stop. Videos of the operation released by the Navy show the pirates using the crew members as human shield as warning shots were fired from the Kolkata. The entire operation was supported by INS Subhadra, UAVs, and P-8I aircraft. A platoon of 8 MARCOS commandos were air dropped from a C-17 Globemaster of the Indian Air Force. The warship called upon the pirates to surrender and to release the vessel and the crew from Bulgaria, Angola and Myanmar who were being held hostage. No injuries were sustained during the operation, and the ship was checked for illegal arms, ammunition, and contraband. The Navy reported that the ship, carrying approximately 37,800 tonnes of cargo worth over $1 million, would be brought safely to the nearest port after assessment of seaworthiness and essential repairs were undertaken by the naval technical team, for making the ship fit for further voyage. INS Kolkata, carrying the 35 pirates, later docked at Mumbai Harbour and handed over the pirates to the Mumbai Police, marking the conclusion of Operation Sankalp. The pirates would later be taken for medical examination. After that, they will be produced before a court on 24 March 2024.

• INS Kochi - sister-ship and second of the class.
• INS Chennai -sister-ship and third of the class.
• HMS Calcutta