Scorpene-Class Sub INS Kalvari is Commissioned

Kalvari-Modi l20171214119324
Prime Minister Narendra Modi on the INS Kalvari in Mumbai on Thursday. Image Credit: PIB

Following a delay of five years, the Indian Navy commissioned its first Scorpene-class submarine, INS Kalvari in Mumbai on Thursday. It’s the first diesel-electric submarine to join the Indian Navy since the Russian-made INS Sindhushastra was inducted in 2000.

The submarine was formally commissioned by Prime Minister Narendra Modi, who called it ‘a fine example of the fast growing strategic partnership between India and France’.

Scorpenes are designed by the French company Naval Group, formerly known as DCNS. They’re currently being built by Mazagaon Dock Limited (MDL) as part of an INR 24,000 crore deal for six submarines. Besides the Kalvari, a second Scorpene, the INS Khanderi, is presently undergoing sea trials and is expected to be commissioned next year. MDL is scheduled to deliver the remaining four Scorpenes by 2020.

The 67.5-metre-long Kalvari has a displacement of 1,585 tonnes and can travel at 20 knots when submerged. Kalvari is also highly automated, and will be able to run with a crew of just 31, leaving space for six special forces soldiers who can be deployed at sea by the vessel.

The submarines will be propelled by a French-made permanent magnetic synchronous motor that will be powered by 360 lead acid batteries, each of which will weigh 750 kilograms. The batteries themselves will get their charge from two 1,250 KW diesel engines.

INS Kalvari during torpedo firing trials earlier this year. Image Credit: Indian Navy via Wikimedia Commons

Delhi Defence Review’s Saurav Jha has a detailed description of the submarine’s features as well as an earlier piece describing plans to install an air independent propulsion (AIP) system. AIP systems offer an alternative source of electricity to the diesel engines, allowing submarines like the Scorpene to be very quiet underwater. DRDO’s Naval Materials Research Laboratory (NMRL) based in Ambernath, Maharashtra, is presently developing an AIP system based on a phosphoric acid fuel cell. But it’s not going to be ready in time for any of the remaining Scorpenes, which means it will have to be expensively retrofitted at some point in the future.

For the moment however, INS Kalvari will still be able to run relatively silently, partly because its efficient motor is ‘mounted on a shock-resistant cradle,’ according to Jha. The Scorpene-class vessels will be especially stealthy in comparison to India’s first generation nuclear submarines, which are generally thought to be noisy.

The Kalvari was supposed to be armed with heavyweight Black Shark torpedoes, but the deal to buy them was scrapped after the manufacturer’s parent company, Leonardo-Finmeccanica was embroiled in corruption allegations.

At present, Kalvari will be armed with wire-guided SUT torpedoes, an ageing munition India purchased from West Germany in the 1980s. More promisingly, it’s also armed with Exocet SM39 anti-ship missiles. It will be many years before India’s fleet of six Scorpenes is better armed and fully ready, but the launch of the Kalvari remains a significant landmark.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Create a website or blog at

Up ↑

%d bloggers like this: