The Kolkata class destroyers are the largest surface warfare ships that India has built indigenously as a follow on project to the Delhi Class destroyers. The project is coded as Project 15A. There are 3 ships under this class that are INS Kolkata, INS Kochi and INS Chennai. The hull of the Delhi Class has been kept as is and there has been huge changes to the superstructure of the ship to incorporate modern sensors, armament and stealth. The construction of the first ship i.e INS Kolkata started in September 2003 at Mazagon Docks Mumbai.
As mentioned earlier the ship is currently the largest destroyer made in India and displaces around 7400 tons at full load. The length of the ship is 163m with the beam length of 17.4m. The propulsion of the ship is handled by the twin Zorya M36E gas turbine plants with 4xDT-59 reversible gas turbines and 2xRG-54 gearboxes. This propulsion enables the ship to attain speed in excess of 30 knots(55 km/hr) and has a range of 800 nautical miles (1500km) while cruising at a speed of 18 knots(33 km/hr). The ships of this class has a crew strength of 325.
The Kolkata Class Destroyers are also the first Indian ships to be equipped with the AESA RADAR. IAI MF-STAR S-band AESA multi function radar replaces many other sensors and radars and takes up their complete functionalities itself. This enabled the ship designers to incorporate higher stealth element to the ship as there was more free space for them to improve the design of the superstructure. The MF-STAR has 4 static panels placed on a specially built mast.
It performs various functions like
- Long range surface surveillance
- Long range 3D air surveillance
- Gunnery control
- Target classification
- Simultaneous multi-engagement support
- Guidance for active and semi active missiles
A second long range RADAR is also used by the Kolkata class in the form of Thales LW-08 2D D-band air search radar which acts a surveillance radar for the early detection of targets.
Looking at the armament of these ships one can easily say that it is one of the most heavily armed warships in the world with a complement of 16 VLS cells of Brahmos missiles which are considered as the deadliest missiles in the world due to their supersonic speed which renders any present air defence systems obsolete.
Its kinetic energy at the time of the impact contains enough force to knock down any ship. The secondary armament for the Kolkata class is in the form of 76mm Oto Melara Super Rapid gun, which can fire 120 rounds in 1 minute up to a distance of 15 km against ground targets and 8 km against aerial targets. It is said that the ships in this class has a lot of deck space still available which will be used up in the next refit of the ships in order to add new missiles to the ships and it is expected that by that time the subsonic Nirbhay cruise missiles will be inducted and these ships would be armed with it in addition to the Brahmos.
In regards to the air defence capability of the ships then these ships have a 2 layered air defence system which is spearheaded by the loadout of 32 Barak 8 missiles which have been jointly developed by India and Israel and recently completed their development trials and are now being inducted into the Israeli Navy.
These missiles have a range of 90+km and can also engage targets at a range as low as 0.5 km where other SAMs of the same class can engage targets only upto a distance of 3-5 km. The secondary layer of defence is provided by the 4xAK-630 CIWS 6 barreled, 30mm Gatling guns which acts as a last ditch effort against the incoming missiles. Its effective range is up to 4 km. The 76 mm main gun also has excellent anti-air capability and can complement the CIWS with its effective range of 8 km against aerial threats. All these guns are open loop and depend on the sensors and radars mounted on the ship.
The ships in this class are also capable submarine hunters. These ships have been equipped with the sensors like the indigenously developed HUMSA-NG bow SONAR and BEL Nagin towed array SONAR. Armament wise the ships 4x 533m has torpedo tubes which can fire long range heavyweight torpedoes at a range of 40 km. In addition to this the ship is also equipped with the RBU-6000 rocket launching system. This unique system can launch a variety of ASW rockets fitted with mines, explosives or decoys. 2 launchers with a total of 24 rocket tubes and 192 reloadable rockets are carried. This system has a range of 6 km max which makes it effective against submarines in littoral and blue water regions. It can also act as a hardkill measure against incoming torpedoes if sufficient warning is there.
In addition to all the above feature the ships of this class are equipped with a hangar which can support up to 2 helicopters which can be used in the anti submarine warfare or any rescue operations. The helicopters can also act as targeting system for the ship. Currently Sea King or HAL Dhruv can be used on the ship.
It is a multi role ship and hence it can be used for any kind of mission at any given point of time. The major selling point of this class is its surface warfare capabilities and we can expect it to be more heavily armed in the next refits. Its sensor suits are also top notch with the AESA radar which handles many functions simultaneously thus incorporating better mission integration and presenting less load on the crew. Although the construction of these ships have delayed but these ships have added a feather on the cap of the Indian shipbuilding industry which is taking steps toward complete indigenisation of ship building.