Classification of Indian Submarines: Kalvari, Arihant, and Akula Classes
The Indian Navy operates a mix of conventional and nuclear-powered submarines to secure its maritime borders. These submarines are divided into different “classes.” A class is a group of ships or submarines built to the same basic design.
Here is a detailed explanation of the Kalvari, Arihant, and Akula classes.
The Kalvari Class
The Kalvari class represents India’s modern fleet of conventional submarines. They are built to patrol the oceans, protect sea routes, and attack enemy ships.
- Type: Diesel-Electric Attack Submarine (SSK).
- Propulsion: They run on diesel engines and electric batteries. Because diesel engines need oxygen, these submarines must come near the surface every few days to breathe through a tube called a snorkel.
- Origin: Built in India by Mazagon Dock Shipbuilders Limited (MDL) under Project-75, using technology from France.
- Weapons: They carry heavyweight torpedoes and anti-ship missiles to destroy enemy vessels.
- Examples: INS Kalvari, INS Khanderi, INS Karanj, INS Vela, INS Vagir, and INS Vagsheer.
The Arihant Class
The Arihant class is the most strategic and highly classified submarine programme in India. These submarines are not meant for everyday patrols; their primary job is to provide a guaranteed nuclear counter-attack if India is ever attacked with nuclear weapons.
- Type: Nuclear-Powered Ballistic Missile Submarine (SSBN).
- Propulsion: They are powered by a miniature nuclear reactor. Nuclear reactors do not need oxygen, meaning these submarines can stay hidden deep underwater for several months without coming to the surface.
- Origin: Completely indigenous. Built in India under the secretive Advanced Technology Vessel (ATV) project.
- Weapons: They carry nuclear-tipped ballistic missiles, such as the K-15 (Sagarika) and the K-4. This completes India’s “Nuclear Triad“—the ability to safely launch nuclear weapons from land, air, and sea.
- Examples: INS Arihant, INS Arighaat, and INS Aridhaman.
The Akula Class
India does not yet build its own nuclear-powered attack submarines. To train Indian sailors and gain a tactical advantage, India leases the highly capable Akula-class submarines from Russia.
- Type: Nuclear-Powered Attack Submarine (SSN).
- Propulsion: Like the Arihant class, they run on nuclear power and can stay submerged for months. However, unlike the Arihant, they do not carry nuclear missiles.
- Origin: Russian-built submarines leased to the Indian Navy.
- Role: They are designed to travel at high speeds underwater, hunt down enemy submarines, and protect India’s own naval fleet.
- Examples: India previously operated INS Chakra I and INS Chakra II on lease. A new agreement has been signed with Russia for the lease of another Akula-class submarine (expected to be named Chakra III), which is scheduled to arrive around 2028.
