Visakhapatnam-class destroyer

In 2009, the Defence Acquisition Council (DAC) - India's top arms-procurement agency subordinate to the Ministry of Defence (MoD), approved of the procurement of four 6,800 tonne destroyers - classified as "Project-15B", as a complement to the Kolkata-class destroyers, which was then under construction.[10] No competitive tender was issued for the construction of the aforementioned destroyers, since Mazagon Dock Shipbuilders Limited (MDL) - a leading naval shipyard, was the only firm capable of constructing guided-missile destroyers at the time.[11]

The objective of the project was to a line of destroyers similar to the earlier Kolkata-class destroyers (Project-15A), but only slightly different "incrementally" - in terms of weaponry and sensors - this was envisaged to minimize the construction-period of the specified class and to reduce costs.[10]

In January 2011, the Indian Navy contracted MDL for the construction of the four designated destroyers.[12]

The keel of the first ship, Visakhapatnam, was laid in October 2013 and it was launched in April 2015.[13][14] Visakhapatnam successfully concluded its basin trials in December 2020, and commenced sea trials in 2021; she was delivered to the Indian Navy on 28 October 2021.[15][16][17] She was commissioned on 21 November 2021, at the Indian Navy's Western Naval Command, headquartered in Mumbai.[18][19]

Mormugao was launched in September 2016. She completed its basin trials on 14 December 2021 and put to its sea trials on 19 December, coinciding with the 60th anniversary of Goa Liberation Day.[20][21] Mormugao is expected to be commissioned by 2022.[22]

Imphal was launched in April 2019.[23][24] Surat, the final ship of the class, was laid down in July 2018.[25]

The vessels of the class are equipped with a OTO Melara 76 mm naval gun. Originally, the Indian Navy had planned to equip the vessels of the class with the Mk-45 127 mm naval gun, manufactured by BAE; however, this plan was reported to have been scrapped, on grounds of financial issues.[26] For point defence, the vessels are equipped with four AK-630M close-in weapon systems (CIWS), with two systems on either side of the superstructure.[27]

For anti-air warfare (AAM), the destroyers are equipped with 32 Barak-8ER surface-to-air missiles (LR-SAM), in four 8-cell VLS.[28] For anti-surface warfare (ASuW), the destroyers are equipped with 16 BrahMos anti-ship missiles (AShM) (also used as land-attack missile (LAM)), enclosed in two 8-cell VLS at the bow.[3]

For anti-submarine warfare (ASW), each destroyer is equipped with two twin torpedo launchers - presumably for launching the Varunastra heavyweight torpedo, developed by the DRDO.[3][29] The destroyers are also equipped with two RBU-6000 (RPK-8) anti-submarine rocket launchers, for firing ASW rockets[3]

Each destroyer is equipped with a helicopter hangar to accommodate two medium-sized helicopters – primarily the HAL Dhruv, or the Westland Sea King Mk. 42B; the ships are equipped with a "rail-less" helicopter traversing system, meant for securing the helicopter, in case of adverse weather conditions at sea.[3]

The destroyers feature the IAI EL/M-2248 MF-STAR S band active electronically scanned array radar, for tracking both air and surface targets.[3] The destroyers are also equipped with the Thales LW-08 D-Band air-search radar, for tracking/monitoring aerial targets.[30]

For underwater surveillance, the destroyers are equipped with the BEL HUMSA-NG bow sonar, and the BEL Nagin active towed array sonar.[31]

The destroyers feature the "Shakti" electronic warfare (EW) suite - developed by the Defence Electronics Research Laboratory (DLRL), for defense against anti-ship missiles and for the interception, detection, classification, identification and jamming of conventional radars.[32] "Shakti" is equipped with wide-band electronic warfare support measures (ESM), electronic countermeasures (ECM), an integrated "Radar Finger Printing System (RFPS)" and a data-recording replay feature for "post-mission analysis".[33][34] The destroyers also reportedly feature the "Deseaver Mk-II" ECM suite, manufactured by Elbit Systems.[31]

As for the class' defensive abilities, each destroyer is equipped with two Kavach anti-missile decoy systems – for neutralizing aerial threats.[27]

The P-15A (Kolkata-class) destroyers and the P-15B (Visakhapatnam-class) destroyers have no major physical differences, except for the differing bridge layouts; the bridge of the P-15B destroyers starkly differs to that of the P-15A – they were designed in such a way so as to reduce radar cross-section (RCS), and to improve survivability.[3][35]

The P-15A and the P-15B destroyers differ from each other, in terms of equipment.[36][37]

• The Visakhapatnam-class is armed with a Mk-45 127 mm naval gun, while the Kolkata-class is armed with an OTO Melara 76 mm naval gun. (The plan to equip the Visakhapatnam-class with the Mark 45 127 mm gun was scrapped on grounds of financial issues, and was replaced with the OTO Melara 76 mm gun).[26]
• The sonar will be relocated from the hull to the bow.
• A revised bridge layout and mast design to reduce radar cross-section (RCS).
• A "rail-less" helicopter traversing system to secure the helicopter, in case of adverse weather conditions at sea.
• A network-centric layout with a Ship Data Network (SDN), an Automatic Power Management System (APMS) and a Combat Management System (CMS).