Delhi - class destroyer The " Delhi " class destroyers are guided - missile destroyer s of the Indian Navy . Three ships of this class are in active service . The " Delhi " class vessels are the largest warships to be fully designed and built in India , although they will soon be superseded by the " Kolkata " class destroyer s and the " Vikrant " class aircraft carrier . They were built at Mazagon Dock Limited in Mumbai . Development . The development of the ship began as Project 15 in 1977 . The ships were designed indigenously and built by Mazagon Docks Limited ( MDL ) at a cost of Rs 7 Billion each . The " Delhi " class has both Soviet and Western design influences , incorporating elements of the " Sovremenny " class destroyer , the " Rajput " class ( " Kashin - II " ) destroyer , and the " Godavari " class frigate . These vessels are fully fitted with flag facilities . The " Delhi " class is also capable of operating in a NBC environment . Radar cross - section reduction is presumed to be minimal , to the extent that some sharp angles have been flattened . In the main air defence role , a pair of 2 3S - 90 launchers - one installed forward of the bridge and the other atop the dual helicopter hangar - are fitted with the Shtil SAM system . The Shtil system consists of the Russian Shtil missile and 24 such missiles are carried in a below - decks magazine . The launchers elevate up to 70° but have a limited firing arc of 30° within the centreline . The launcher groups require a crew of 20 men and weigh about 50 tons . 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 500m to 10 km . The missile ' s maximum range is 32 km . The ship has a surveillance capacity of over 350 km and can sterilise an area of 250 km . The ships also have a quadruple 533mm torpedo launcher , which 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 . It is also equipped with two RBU - 6000 anti - submarine rocket launchers with 12 tubes . Their range is 6 km and the maximum engagement depth is 500m . Each ship can support two helicopter s , the Sea King or the HAL Dhruv . The Sea King helicopters are equipped with a Super Searcher radar and primarily used in air surveillance and anti - submarine roles . The helicopters are capable of flying four and half hours non - stop . The HAL Dhruv helicopters are primarily for utility roles . The INS " Delhi " has a crew of approximately 30 officers and 350 sailors . The ships are equipped with four chaff launch systems and the BEL Ajanta radar interceptor . The TQN - 2 jamming system is supplied by the Italian company , Elettronica . The ship ' s hull mounted active search sonar capability is based on the TSM2633 by Thales Underwater Systems or the APSOH by Bharat . The " Delhi " Class also has a variable depth sonar , Model 15 - 750 developed and manufactured in India by Indal and Garden Reach .