This torpedo is powered by an electric propulsion system with multiple 250 kW (340 hp)Silver Oxide-Zinc (AgOZn) batteries.[10] It can achieve speeds in excess of 40 kn (74 km/h; 46 mph), weighs around 1.5 tonnes and can carry 250 kg (550 lb) of conventional warhead. This torpedo has more than 95 per cent indigenous content. Varunastra has conformal arraytransducer which enables it look at wider angles than most common torpedoes. It also has an advanced autonomous guidance algorithms with low drift navigational aids, insensitive warhead which can operate in various combat scenarios. It is the only torpedo in the world to have a GPS-based locating aid.[2][11][12] The exercise variant of Varunastra has integrated instrumentation system for recording all the dynamic parameters of the weapon, redundancy in recovery aids in case of emergency shut down or malfunction.[2]
In May 2014 it was reported that theIndian Navy is scheduled to carry out User Evaluation Trials (UETs) during the mid-year period. The assembly of the prototype was done by a team fromBharat Dynamics Limited at the Talwar facility of NSTL inVisakhapatnam.[13]
In thefinancial year 2015-16, the torpedo underwent 130 technical trials while 14 user trials were conducted between January and March 2015. In September 2015, MoD granted final approval for the torpedo's User Evaluation Trials (UETs) and eventually it was accepted for induction into Services.[12]
The development of the first variant — ship-launched, anti-submarine variant — of the torpedo was completed in July 2016. The overall development period was 11 years.[14]
The variant of Varunastra torpedo was formally inducted in the Indian Navy by defence ministerManohar Parrikar on 26 June 2016.[1][14] The minister in his speech said that theGovernment is in favour of exporting the torpedo to friendly nations includingVietnam.[15][16] With some minor modifications the submarine variant of the torpedo is to be test fired shortly.[17]
DuringAero India 2017, it was reported that DRDO has begun test-firing of a submarine-launched variant of the torpedo. ASindhughosh-class submarine is being used as the launch platform for the development. The variant was reportedly accepted and ready for production.[18][19]
On 5 June 2023, Varunastra was fired by aKamorta-class corvette at an Under Water Target System (UWTS) laid byINSJalashwa. This was the first trial where the torpedo was equipped with High Explosive (HE) live warhead.[20] On 6 June, the Navy successfully conducted a combat trial of Varunastra where the torpedo was fired from a submarine and successfully hit an underwater target.[21][12][22]
4 July 2016: Order for the first batch of 73 torpedoes at a cost of₹8,760crore (equivalent to₹130 billion or US$1.5 billion in 2023) was placed. The technology was formally handed over to BDL for production. The torpedo will have an indigenous content of 95%. The torpedo was also inducted by the Navy.[14][24] All future anti-submarine warfare ships will be capable of firing Varunastra.[25][26]
11 April 2018: BDL signed a Licensing Agreement for Transfer of Technology with NSTL for the production, testing and maintenance of Varunastra torpedoes.[27][28]
14 June 2019:Ministry of Defence awarded a contract worth₹1,187 crore (equivalent to₹15 billion or US$170 million in 2023) to BDL to supply 63 Varunastra torpedoes to the Indian Navy.[29][30]
February 2020: Reports suggested that first batch of torpedoes from second order would be delivered soon.[30][31]
20 March 2025: Defence Acquisition Council (DAC) cleared the Acceptance of Necessity for an additional batch of ship-launched variant of Varunastra Torpedo (Combat).[32]
Shakti heavyweight torpedo uses thermal propulsion technology in contrast to the Varunastra torpedo which uses electric propulsion. The torpedo employsmonopropellant fuel, which allows combustion to take place without aerial oxygen, and apumpjet. Its propulsion unit generates 400 kW of power for faster acceleration. A newer propulsion unit is under development which will be producing 500 kW of power .It can operate at a maximum depth of 600 metres (2,000 ft), a maximum speed of 60 knots (110 km/h; 69 mph). The first image emerged publicly inTwitter on 9 June 2023 which hinted that the torpedo is going sea trials.[33][34][35][36]
Takshak torpedo is the advanced version of the Varunastra torpedo which employs an electric battery for propulsion. It has a length of 6.4 metres (21 ft) which is shorter from the previous variant, enabling to be launched from submarines. It also featuresring laser gyroinertial navigation system (RLG INS) as well asGPS/NavIC-based guidance. Takshak has 2 variants: submarine-launched with optical fiber guidance and ship-launched with autonomous guidance. The torpedo, as of May 2024, is ready for sea trials with the Indian Navy which will pave way for induction for deployment.[37][38]
^Chauhan, AVSM & Bar, VSM, Retd Vice Admiral Pradeep (9 February 2017)."India's Submarine Arm — Returning to Even-Trim".Center for International Maritime Security. Retrieved30 December 2024.{{cite web}}: CS1 maint: multiple names: authors list (link)
Indian Navy
