Name Kolkata class Operators Indian Navy Succeeded by Visakhapatnam class | Builders Mazagon Dock Limited Preceded by Delhi class Built 2003 - 2015 | |
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The Kolkata class (Project 15A) are a class of stealth guided missile destroyers constructed for the Indian Navy. The class comprises three ships – Kolkata, Kochi and Chennai, all of which were built by Mazagon Dock Limited (MDL) in India, and are the largest destroyers to be operated by the Indian Navy. Due to delays in their construction, and a problem found during the sea trials, the initial commissioning date of the first ship of the class had been pushed back from 2010 to 2014. The final ship commissioned was Chennai, in November 2016.
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The destroyers are a follow-on of the Project 15 Delhi-class destroyers, but are considerably more capable due to major improvements in the design, the addition of substantial land-attack capabilities, and the fitting-out of modern sensors and weapons systems.
Development
In 1986, the Cabinet Committee on Political Affairs (CCPA) approved a follow-on class of the earlier Project 15 Delhi-class destroyers. The aim was that the follow-on class would incorporate a higher level of air-defence, land attack, anti-submarine and anti-ship capabilities than the preceding class. However, the Indian Navy did not initially take up the option. By the year 2000, the Indian Navy had redesigned the follow-on Kolkata class to incorporate even higher levels of technology (including modern stealth characteristics) and in May of that year, approval for the construction was given. Concept and function for Project 15A was framed by the navy's Directorate of Naval Design, while the detailed design was developed by Mazagon Dock Limited (MDL).
Construction
Construction of three Kolkata-class ships was sanctioned by the Government of India in May 2000, and steel for the lead ship was cut in March 2003. Construction began in September 2003 at Mazagon Docks, Mumbai, with an initial expectation that the first of the class would be handed over to the navy by 2010. However, since then the Kolkata class has suffered consecutive delays, slow construction procedures and technical problems which saw the first ship of the class enter service during mid 2014. The delays in the construction programme have been attributed to persistent design changes made by the Indian Navy to incorporate new weapons systems and sensors, failure by a Ukrainian shipyard to deliver the ship's propellers and shafts and the contract later being awarded to a Russian firm, and finally the delay in the delivery of the Barak 8 anti-air missiles, which are still in the final stages of completion with Israel Aerospace Industries and the Defence Research and Development Organisation.
The Kolkata class are the largest destroyers ever to be constructed at Mazagon Docks, and as of 2013, all three ships of the class have been launched and are being fitted out. Technical problems were found during the sea trials of the lead ship Kolkata, which delayed the project by six months to early 2014.
Design and description
The Kolkata class share similar dimensions to the previous Delhi class, however they have 2,363 modifications which include major upgrades in weaponry, sensors and helicopter systems. With a standard displacement of 6,800 t (6,700 long tons; 7,500 short tons) and a full-load displacement of 7,400 t (7,300 long tons; 8,200 short tons), they are the largest destroyers ever operated by the Indian Navy. Some media reports have even given a full-load displacement of 7,500 t (7,400 long tons; 8,300 short tons). These are the first stealth destroyers being built by India and marked a significant development in India's shipbuilding technology. The ships would incorporate modern weapons and sensors, and will have an advanced information warfare suite, an auxiliary control system with a sophisticated power distribution architecture, and modular crew quarters.
The class have a length of 163 m (535 ft), a beam of 17.4 m (57 ft) and a draught of 6.5 m (21 ft). The ship's power and propulsion features a standard Combined gas and gas system utilizing twin Zorya M36E gas turbine plants and four DT-59 reversible gas turbines. The class also features two KVM diesel engines. On-board Wartsila WCM-1000 generators and Kirloskar AC generators supply the ship's electricity. The two propellers are run via two RG-54 gearboxes. This configuration allows the ship to reach speeds in excess of 30 kn (56 km/h; 35 mph). Aviation facilities include a large flight deck, which was re-designed to handle larger helicopters than the Delhi-class, and an enclosed hangar for up to two maritime helicopters.
The primary radar sensor of the class is the EL/M-2248 MF-STAR multi-mission AESA. It is also equipped with Thales LW-08 long range volume search radar and EL/M-2238 S-band STAR surveillance radar from Israel Aerospace Industries. A Nagin active towed array sonar and a bow-mounted sonar HUMSA-NG (hull-mounted sonar array - new generation) are carried for sub-surface surveillance. To protect against anti-ship missiles coming from multiple directions, the ship carries the Elbit Systems Deseaver MK-II decoy control and launching system.
The ship's main air-defence armament is composed of two 4x8-cell vertical launching systems (VLS) allowing for up to 32 Barak 8 (medium-long range) air-defence missiles. In addition, four AK-630 CIWS are fitted for close-in defence.
The supersonic BrahMos anti-ship and land-attack missiles are the primary offensive armament of the Kolkata-class. The BrahMos missiles are fitted into a 16-cell Universal Vertical Launcher Module (UVLM) allowing one missile per launch silo, and all 16 missiles can be fired in salvo. Perhaps the most distinctive and noticeable armament of the Kolkata class is its 76 mm (3.0 in) naval gun located forward of the bridge. The 76 mm gun provides limited anti-shipping capability and anti-air capability in addition to its naval gun fire-support role for land based operations. For anti-submarine warfare, the Kolkata-class are equipped with a torpedo launching system via four torpedo tubes and two RBU-6000 anti-submarine rocket launchers. BEL's Electronic Modular Command & Control Applications (EMCCA) Mk4 provides combat management.
Four million lines of codes have been written to develop the advanced combat management system onboard INS Kochi. The system is designed so that all the data about the surrounding threat comes in one place, along with analysis about the kind of threat. The system also advises the commanding officer about the kind of weaponry he should use to tackle the threat. Obviously, all this happens in real-time. The Ship is equipped with sophisticated digital networks, such as Asynchronous Transfer Mode based Integrated Ship Data Network (AISDN), Combat Management System (CMS), Automatic Power Management System (APMS) and Auxiliary Control System (ACS). The AISDN is the information highway on which data from all the sensors and weapon ride. The CMS is used to integrate information from other platforms using indigenous data-link system, to provide Maritime Domain Awareness. The intricate power supply management is done using APMS, and remote control and monitoring of machinery is achieved through the ACS.
Ships of the class
Initially in 2008, the total program cost with long-term spare parts was expected to cost ₹3,800 crore (US$560 million), but the construction costs escalated about 225%, and by 2011, cost of the program became ₹11,662 crore (US$1.7 billion), with each ship costing ₹3,900 crore (US$580 million). The Defense Minister A. K. Antony cited the causes being the delay in supply of warship-grade steel by Russia, increase in costs of Russian specialists due to inflation during the build period, wage revision due from October 2003 and delay in finalisation of cost of weapons and sensors.