A torpedo's looming endurance test

The Varunastra is being developed for range and speed to take on future submarine threats in the region

3 min read
Updated On: Oct 14 2025 | 3:45 PM IST
An advanced heavyweight torpedo, Varunastra, weighing around 1850 kilograms and has acoustic-homing abilities which enables targeting of silent submarines (Photo: Indian Navy)

The advanced heavyweight torpedo, Varunastra, which weighs around 1,850 kilograms and has acoustic-homing abilities, can target silent submarines (Photo: Indian Navy)

The Varunastra, named after the sea god in Hindu mythology, is an advanced heavyweight torpedo that is fitted on Indian warships.

The electrically propelled torpedo can be fired from ships at submarines, both in deep and shallow waters.

The torpedo weighs around 1,850 kilogrammes (kg) and can reach depths of 600 metres while travelling between 40 and 50 knots. It has a range of around 40 kilometres. It was inducted in 2016 after being designed by the Defence Research and Development Organisation (DRDO), the government agency, as part of the Indian Navy’s underwater weapons suite.

It is being developed further for range, speed, and to enable it with artificial intelligence. The torpedo is likely to be deployed on all future anti-submarine ships in India.

“It remains the weapon of choice,” a former high official of the Indian Navy said, adding that the torpedo’s role in warfare will continue to be crucial, especially with submarine-based threats expected to rise in the future.

Increasing the torpedo’s “great endurance” will boost the Navy’s overall weapons capability, a current source said. A combat variant of the Varunastra was successfully test-fired at sea, using a live warhead, in 2023.

“There are various ways of initiating the explosion,” the Navy source said, without providing details.

The warhead is thought to be at least 250 kg. The weapon itself was 1,500 kg in the 2016 version.

The torpedo’s acoustic-homing ability makes it capable of targeting silent submarines, according to Bharat Dynamics Ltd, the public company that makes it. The first batch of 73 torpedoes cost the Navy ₹8,760 crore ($987,153), a previous media statement by the government said. Many more were ordered after that.

In March, the Defence Acquisition Council cleared the “acceptance of necessity” for a newer batch of the ship-launched variant of the Varunastra. Trials for a submarine-launched variant are ongoing.

Pakistan is buying diesel-electric attack submarines from China. Based on the Chinese Navy’s Yuan-class platform, three such submarines have been delivered until August, and one is awaited. Four others will be reportedly made in Pakistan under a transfer-of-technology arrangement.

These purchases will affect the regional power dynamics, according to defence analysts.

With such scenarios in mind, the DRDO’s naval design unit and the Indian Navy have increased the focus on developing advanced weapons; underwater decoys, including anti-torpedo; water mines (different kinds such as moored and ground); ship-fire control systems; sonars; supportive marine vehicles; and stealth technology for naval platforms.

 

Premium ContentPremium ContentSubscription ExpiredSubscription Expired

Your access to Blueprint has ended. But the story is still unfolding.

No longer a subscriber? There’s a new reason to return.

Introducing Blueprint - A magazine on defence & geopolitics

Introducing Blueprint - A magazine on defence & geopolitics

Like what you read? There’s more in every issue of Blueprint

From military strategy to global diplomacy, Blueprint offers sharp, in-depth reportage on the world’s most consequential issues.

Exclusive pricing for Business Standard digital subscribers

Choose your plan

Exclusive Pricing

Choose your plan

58% off
₹6,000

Blueprint Digital

₹2,500

annual (digital-only)

₹208/Month

70% off
₹12,000

Blueprint Complete

₹3,500

annual (digital & print)

₹291/Month

41% off
₹6,000

Blueprint Digital

₹3,500

annual (digital-only)

₹291/Month

62% off
₹12,000

Blueprint Complete

₹4,500

annual (digital & print)

₹375/Month

Here's what's included:

  • Access to the latest issue of the Blueprint digital magazine

  • Online access to all the upcoming digital magazines along with past digital archives

  • * Delivery of all the upcoming print magazines at your home or office

  • Full access to Blueprint articles online

  • Business Standard digital subscription

  • 1-year unlimited complimentary digital access to The New York Times (News, Games, Cooking, Audio, Wirecutter, The Athletic)

Written By :

Satarupa Bhattacharjya

Satarupa Bhattacharjya is a journalist with 25 years of work experience in India, China and Sri Lanka. She covered politics, government and policy in the past. Now, she writes on defence and geopolitics.
First Published: Oct 07 2025 | 12:34 PM IST

Next Story