The Delhi class Destroyers were the first destroyer class ships that India designed and built indigenously which was started as the Project 15 in 1977. There are 3 ships under this class that were manufactured for the Indian Navy and the last ship was delivered to the Indian Navy in 2001. All the ships were constructed at the Mazagon Docks Limited at the cost of ₹ 7 billion for each ship. The three ships have been named as INS Delhi (D61), INS Mysore (D60) and INS Mumbai (D62). The Delhi class has both Soviet and Western design influences, incorporating elements from the Sovremenny, Rajput and Kashin-II class destroyers and the Godavari class frigates.
The Delhi class destroyers at the time of its designing and building was the largest ship that was to be built for the Indian Navy in India. It’s total displacement stands at 6,200 tons at full load. It has a hull length of 163m and a beam width of 17.4m. The propulsion of the ship is handled by 2 × M36E gas turbine plants with 4 × DT-59 reversible gas turbines which can churn out power of 48,000 kW and can propel it to a speed of over 28 knots (52km/hr). The ships of this class has a range of 8,000 km and has a complement of 350 sailors (incl. 40 officers).
The Delhi Class destroyers are equipped with various sensors and suites which makes it a multi role platform making it capable of operating in any kind of environment and for undertaking any kind of missions. The primary RADARs fitted in these ships are the MR-775 Fregat MAE air search radar and the Bharat RAWL (Dutch Signaal LW08) surface search radar. There are 3 more secondary radars in the form of MR-212/201 Vaygach-U navigation radars. All the RADARs on the ship enable it to have a surveillance range of 350 km. For the anti submarine roles these ships are fitted with the indigenously developed HUMSA SONAR and also has a Garden Reach Model 15-750 variable depth sonar or Thales ATAS.
These ships are classified as the guided missile destroyers and hence has their main weapons as the 16 * Kh-35 Switchblade which are the main offensive weapons of the ship against any enemy ship. The Delhi class ships lacks VLS cells for the main missiles and hence these missiles are fitted in the 4 × quadruple KT-184 launchers. The Kh-35 Switchblade is a subsonic cruise missile having a range of 130 km and can travel at a cruise speed of 0.8 km. The secondary armament for these ships is in the form of the 100mm AK-100 gun which has a maximum fire rate of 60 rounds per minute, firing a 26.8 kg munition in HE anti-air or HE fragmentation varieties.
At the time of its construction the Delhi class was equipped with the Shtil SAM system which were responsible for the air defence of the ship. A pair of 2 3S-90 launchers – one installed forward of the bridge and the other atop the dual helicopter hangar are fitted on the ship and launch the Russian Shtil missiles from below decks magazine which contains 24 missiles each and thus each ship carries 48 missiles Shtil missiles at a time. The launchers elevate up to 70° but have a limited firing arc of 30° within the centreline. The Delhi class is being upgraded with the Rafael Barak 1 point air defence missile system, which overcomes the limited firing arc of the Shtil system. It has an eight-cell vertical launch system and the missile command-to-line-of-sight (CLOS) radar guidance with a range from 500 m to 10 km. The missile’s maximum range is 32 km. The secondary layer of air defence is provided by the 2 × 30mm K-630 gatling guns which acts as the last ditch effort against the incoming anti ship missiles.
For the Anti submarine warfare these ships are fitted with the 2 × RBU-6000 anti-submarine mortar arrays which has a range of 6 km and has maximum engagement depth of 500m thus making it ideal for hunting submarines in littoral waters. These ships also has 5 × 10 533-millimetre (21 in) torpedo tubes. These torpedo launchers can also be used to launch SS-N-15 ‘Starfish’ or possibly SS-N-16 ‘Stallion’ ASW missiles, so is capable of hitting targets ranging from 50 km to 120 km. For ASW and rescue mission roles the Delhi class can hold 2 helicopters in its hangar bay. Currently the Sea King helicopters are being used from these ships.
The Delhi class is a potent multirole platform and thus can act in a fleet or as standalone ship in the enemy waters due to its capability to engage every possible threats. These ships were the largest ships to be designed and built in India and thus acted as a stepping stone to the Kolkata Class destroyers which are the modern derivative of these ships incorporating same hull.