Kolkata-class Guided Missile Destroyer

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.

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
These are the largest warships ever constructed at Mazagon, the oldest Indian naval dockyard. The 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). Seven vessels of the Kolkata-class are under construction at MDL. Aimed at improving the country's naval capabilities, the Project 15 ships will incorporate enhanced stealth features and land-attack capabilities. Project 15 A was conceived as a follow-on of the earlier Delhi-class destroyers and has major advances in its weapons and sensors ans is propelled by four Zarya reversible gas turbines. There was a delay in construction due to defaults by Ukraine in delivering the propellers and shafts and the contract was later awarded to Russia.

Indigenous on-board equipment includes the HUMSA-NG (Hull Mounted Sonar Array – new generation) and the Nagin active towed array sonar. The vessels will also feature BrahMos cruise missiles and the Indo-Israeli Long Range Surface to Air Missile (LRSAM) which has a range of 70 km. Each vessel is expected to cost 38 billion (US$691.6 million), including the cost of spares and maintenance over the ship's life.

Project 15B
In January 2011, the Cabinet Committee on Security gave approval for nine more destroyers under Project 15B, which will be upgraded Project 15A ships. Even though Type 15B retains the hull form of Kolkata-class destroyers, there will be changes in the superstructure that will improve stealth and include better sound and infrared suppression systems. Project 15B differs from Project 15A because of the flush deck. The flush deck improves stealth as it is smoother with less angles and corners. The displacement of each Project 15B will be approximately 8,000 tonnes. As with most Indian designed ships, they will operate two helicopters. The Project 15B will be armed with the Nirbhay land attack cruise missile (1,000 km range), the hypersonic Brahmos-2 anti-ship cruise missile (300 km range) and Extended Range Surface to Air Missile (ER-SAM) also known as Barak 8 (70 km range).

Specifications

 * Type: Stealth Guided Missile Destroyer
 * Service Period: 2014-
 * Characteristics
 * Length: 535 feet (163.07 meters)
 * Beam: 57 feet (17.37 meters)
 * Draft: 21 feet (6.4 meters)
 * Displacement: 6,890 tons (Standard); 7,500 tons (Full Load)
 * Crew: 325
 * Power: 112,000 shp
 * Propulsion:
 * 2 x Zorya M36E gas turbine plants with 4 x DT-59 reversible gas turbines
 * 2 x RG-54 gearboxes
 * 2 x Bergen/GRSE KVM-diesel engines, 9,900 hp (7,400 kW) each
 * 4 x 1mWe Wärtsilä WCM-1000 generator sets driving Cummins KTA50G3 engines and Kirloskar 1MV AC generators
 * Range: 8,000 nautical miles (14,816 kilometers) at 18 knots (33.34 km/hr)
 * Speed: 35 knots (64.82 km/hr)
 * Sensor Suite and Countermeasures:
 * Thales LW-08 D-band air search radar
 * IAI EL/M-2248 MF-STAR AESA milti-function radar
 * IAI EL/M-2238 L-band STAR surveillance radar
 * BEL HUMSA-NG bow sonar
 * BEL Nagin active towed array sonar
 * BEL Electronic Modular Command & Control Applications (EMCCA Mk4) combat management system
 * Countermeasures:
 * Elbit Systems Deseaver MK II countermeasures systems and defensive aids suite
 * Armament:
 * 1 x 100mm gun
 * 4 x 4-cell BrahMos UVLM
 * 2 x 32-cell Barak-8 VLS
 * 2 x AK-630 gatling guns
 * 4 x 8-cell Barak-1 VLS
 * 2 x RBU-6000
 * Aircraft Carried: 2 x Helicopters
 * Aviation Facilities: Flight Deck and enclosed hangar

Unit Run

 * INS Kolkata (D63)
 * INS Kochi (D64)
 * INS Chennai (D65)