Submarine
Also called: Conventional submarine, Diesel-electric submarine · Topic: India's External Relations, 1947-1999: Non-alignment, Wars and Nuclear Policy · NCERT: Beyond NCERT
Meaning
A submarine is a warship that can travel and fight underwater. A conventional submarine is one that does not run on nuclear power. In India's case it is usually a diesel-electric submarine. On the surface it runs on diesel engines, which also charge its batteries. Underwater it runs only on those batteries, so it can stay down only as long as the batteries last. Its main weapons are torpedoes (underwater missiles that hit ships) and mines (hidden explosives laid at sea). It uses a periscope and radar near the surface and sonar (detection by sound) underwater. Submarines matter because they can quietly threaten an enemy's ships and ports.
Example
In October 1976 INS Karanj, a Russian-made conventional submarine, visited Madras harbour while preparations for Navy Day were under way. It showed how much India relied on Soviet arms in the 1970s. The name was later given to a new INS Karanj, commissioned in 2021. It was built in Mumbai by Mazagon Dock Shipbuilders Ltd (MDL) to a French design from Naval Group.
Don't confuse with
- Nuclear-powered submarine: a nuclear reactor runs it, so it does not need to come up to recharge batteries. A diesel-electric boat must come up close to the surface to run its diesels, and at that moment it is easiest to find.
- AIP (air-independent propulsion) submarine: it is still a conventional boat. It carries an extra system that makes power underwater without taking in air, so it can stay submerged much longer than one running on batteries alone.