Indian shipbuilder Mazagon Dock Limited (MDL) delivered “Vela”, the fourth Scorpene type submarine (Kalvari-class) to the Indian Navy. The submarine was launched by MDL on 6 May 2019. Vela is expected to be commissioned with the Indian Navy by year-end. The Kalvari class is a class of diesel-electric attack submarines based on the Scorpène-class submarine being built for the Indian Navy. The class and submarines take their names from the first submarines inducted in the Indian Navy. In 2005, India chose the Scorpène design; purchasing six submarines for US$3 billion (US$500 million per boat). Under a technology transfer agreement, the state-owned Mazagon Docks in Mumbai was to manufacture the submarines
The Kalvari class is capable of offensive operations across the entire spectrum of naval warfare including anti-surface warfare, anti-submarine warfare, intelligence gathering, mine laying and area surveillance. The hull, fin and hydroplanes are designed for minimum underwater resistance and all equipment inside the pressure hull is mounted on shock absorbing cradles for enhanced stealth. Special steel was used in its construction which has high tensile strength, capable of withstanding high yield stress and hydro-static force. Each submarine has 60 km of cabling and 11 km of piping.
It has a length of 67.5 m (221 ft), height of 12.3 m (40 ft), overall beam of 6.2 m (20 ft) and a draught of 5.8 m (19 ft). It can reach a top speed of 20 kn (37 km/h) when submerged and a maximum speed of 11 kn (20 km/h) when surfaced. The class displaces 1,615 t (1,780 short tons) when surfaced and 1,775 t (1,957 short tons) when submerged.The submarine has a range of 6,500 nmi (12,000 km) at 8 kn (15 km/h) when surfaced. Each ship is powered by four MTU 12V 396 SE84 diesel engines, has 360 battery cells (750 kg each), for power and has a silent Permanently Magnetised Propulsion Motor.
This class is equipped with six 533-mm torpedo tubes for a combination of 18 heavyweight wire-guided German-made Surface and Underwater Target (SUT) torpedoes and SM39 Exocet anti-ship missiles or 30 mines in place of both. The class is also fitted with mobile C303/S anti-torpedo decoys for self-defence. The weapon systems and sensors are integrated with Submarine Tactical Integrated Combat System (SUBTICS). It has a sonar system is capable of Low Frequency Analysis and Ranging (LOFAR) enabling long range detection and classification. Each submarine has a complement of 8 officers and 35 sailors.[